Solar power plant
Chapter 1 Background Electricity Generation Capacity in Bangladesh Total Installed Capacity
5803 MW
December - 2009
BPDB
3812 MW
December - 2009
IPP
1330 MW
December - 2009
SIPP & Rental
435 MW
December - 2009
REB
226 MW
December - 2009
PRESENT CAPABILITY
GENERATION5250 MW
Maximum Demand Maximum history :
generation
CONSUMER NUMBER
December - 2009
More than 6ooo MW in 4606 MW 19,22,361
on 14/04/2010 FY-2009
The total installed capacity including IPP( as on june’2009) : Energy source Hydro
Generation capacity 230MW ( 4.19 %)
Steam Gas Turbine Combined Cycle
2638 MW (48.03 %) 997 MW (18.15 %) 1359MW( 24.74 %)
Diesel Total
269MW( 4.89 %) 5493MW(100.00%)
Energy Installed Capacity in Bangladesh
Energy Consumption Non-Renewable (in thousand metric tons oil equivalent)
Energy Type
Bangladesh
Asia
World
Coal and coal products
46
1013218
2278524
Crude oil and natural gas liquids
1098
829930
3563084
Natural Gas
6861
277374
2012559
Nuclear
0
117291
661901
Energy Consumption Renewable (in thousand metric tons oil equivalent) Energy Type
Bangladesh
Asia
World
Hydroelectric
72
44424
222223
Primary solid biomass 7469 (includes fuel wood)
561751
1035139
Biogas and liquid biomass
0
1276
14931
Geothermal
0
14658
43802
Solar
15
865
2217
Wind
2
94
1748
Tide, wave, and ocean
0
0
53
Energy Consumption Sectors (in thousand metric tons oil equivalent)
Sectors Industry
Bangladesh Asia 3721 752092
World 2140474
Transportation Agriculture Commercial & public services Residential Non-energy Uses
1253 467 124
335749 64834 101129
1755505 166287 511555
7880 420
731518 79643
1845475 333981
Energy Consumption Sectors (in thousand metric tons oil equivalent)
Sectors Industry
Bangladesh Asia 3721 752092
World 2140474
Transportation Agriculture Commercial & public services Residential Non-energy Uses
1253 467 124
335749 64834 101129
1755505 166287 511555
7880 420
731518 79643
1845475 333981
Energy Consumption Sectors
Energy is an Engine of Growth • Stable, expanding energy resources are a prerequisite for economic development. • More than two million people are employed in rural areas through electricity-run irrigation pumps, equipment and businesses • Rural businesses with electricity can generate eleven times more jobs than those without electricity. • Bangladesh loses around $1 billion per year due to power outages and unreliable energy supplies.
Load-shedding Free Bangladesh: Dream & Reality • Energy sector experts, in cast doubt on the possibility of solving the short-term power crisis . • Achieving the long term goal to add 9,426 MW of electricity by the year 2015. • GOB has vision to electrify the whole country within the year 2020.
Bangladesh is an energy starved country and large unsatisfied demand for energy Only 40% of the 145 million are connected to the grid •
Only 20% of the rural people have electricity
•
Most rural people depend on kerosene lamps for light
•
80% of the rural people cook with biomass
•
This causes economic health, environmental problems
The Solution New Era of Renewable Energy Technologies Bangladesh has a good potential for Renewable energy. It has plenty of sunshine & an emerging live-stock/poultry business • Stand-alone SHSscan provide better light, & other services at less cost than kerosene • Biogas Technologycan provide cooking gas, lights, electricity, organic fertilizers at minimum costs. At least 4 million plants can be constructed • Improved Cook Stovescan protect women’s health, stop deforestation
Solar Energy is an alternative • Large nos. of population have no access to electricity especially rural poors. • Electricity generation per capita is one of the lowest in the world • 60 percent total generation is consumed by the residential use. • Installing for solar generation in residential houses both in rural and urban areas can play a role in releasing pressure for power demand.
Introduction to Solar Energy • • • • • • • • • •
Technology is easy Affordable cost. Within the ability of poors Basically no maintenance cost. Only source of energy is sunshine. Energy source is cost free. Environmental Pollution is less. No emission PV panels are durable Very few materials are required
Objectives of the Study For Improving and Knowing : • Potential of using solar energy in Bangladesh • Cost effectiveness of using solar energy in Bangladesh • Transforming technology to the users • Developing social awareness • Easing pressure on natural gas • Present status of using solar energy • Substituting energy to national demand • Waste management of the materials for using solar energy • Environmental merits and demerits of using solar energy • Comparisons with other sources of energy
Solar Energy Environments,LLC exists to help utilize sunlight for useful energy in our life. We would like to SEE everyone take advantage of the free sunlight in some way. If we primarily used renewable energy, including Solar, and saved our fossil fuels, our reserves could last for many generations. We SEE many opportunities for our solar energy future - Do We SEE the Light? Utilizing Solar Energy is easier than ever to access a free available resource-the Sun. A Solar Energy system is a wise investment. Solar energy is free, only purchasing the equipment to convert the light to usable energy. No one regulates sunlight, it's already ours. Paying for electricity and gas from the power company is a never ending process, like leasing, minimize or even end that process with solar, by owning your fuel. Much of the world already uses Solar Energy because it is practical, available and reliable.
Chapter 2
An Introduction to Solar Energy 1. What Is Solar Energy? Solar energy is energy that comes from the sun. Every day the sun radiates, or sends out, an enormous amount of energy. The sun radiates more energy in one second than people have used since the beginning of time! Where does all this energy come from? It comes from within the sun itself. Like other stars, the sun is a big gas ball made up mostly of hydrogen and helium. The sun generates energy in its core in a process called nuclear fusion. During nuclear fusion, the sun's extremely high pressure and hot temperature cause hydrogen atoms to come apart and their nuclei (the central cores of the atoms) to fuse or combine. Four hydrogen nuclei fuse to become one helium atom. But the helium atom weighs less than the four nuclei that combined to form it. Some matter is lost during nuclear fusion. The lost matter is emitted into space as radiant energy. It takes millions of years for the energy in the sun's core to make its way to the solar surface, and then just a little over eight minutes to travel the 93 million miles to earth. The solar energy travels to the earth at a speed of 186,000 miles per second, the speed of light. Only a small portion of the energy radiated by the sun into space strikes the earth, one part in two billion. Yet this amount of energy is enormous. Every day enough energy strikes the United States to supply the nation's energy needs for one and a half years! Where does all this energy go? About 15 percent of the sun's energy that hits the earth is reflected back into space. Another 30 percent is used to evaporate water, which, lifted into the atmosphere, produce's rain-fall. Solar energy also is absorbed by plants, the land, and the oceans. The rest could be used to supply our energy needs.
2. History of Solar Energy People have harnessed solar energy for centuries. As early as the 7th century B.C., people used simple magnifying glasses to concentrate the light of the sun into beams so hot they would cause wood to catch fire. Over 100 years ago in France, a scientist used heat from a solar collector to make steam to drive a steam engine. In the beginning of this century, scientists and engineers began researching ways to use solar energy in earnest. One important development was a remarkably efficient solar boiler invented by Charles Greeley Abbott, an American astrophysicist, in 1936. The solar water heater gained popularity at this time in Florida, California, and the Southwest. The industry started in the early 1920s and was in full swing just before World War 11. This growth lasted until the mid- 1950s when low-cost natural gas became the primary fuel for heating American homes. The public and world governments remained largely indifferent to the possibilities of solar energy until the oil shortages of the 1970s. Today people use solar energy to heat buildings and water and to generate electricity.
3. Solar Collectors and Solar Space Heating
Heating with solar energy is not as easy as you might think. Capturing sunlight and putting it to work is difficult because the solar energy that reaches the earth is spread out over a large area. The sun does not deliver that much energy to any one place at any one time . How much solar energy a place receives depends on several conditions. These include the time of day, the season of the year, the latitude of the area, and the clearness or cloudiness of the sky. A solar collector is one way to collect heat from the sun. A closed car on a sunny day is like a solar collector. As sunlight passes through the car's glass windows, it is absorbed by the seat covers, walls, and floor of the car. The light that is absorbed changes into heat. The car's glass windows let light in, but don't let all the heat out. (This is also why greenhouses work so well and stay warm year-round.) So, a solar collector does three things: • • •
it allows sunlight inside the glass (or plastic); it absorbs the sunlight and changes it into heat; it traps most of the heat inside.
Solar Space Heating Space heating means heating the space inside a building. Today many homes use solar energy for space heating. There are two general types of solar space heating systems: passive and active. A "hybrid" system is a mixture of the passive and active systems.
Passive Solar Homes In a passive solar home, the whole house operates as a solar collector. A passive house does not use any special mechanical equipment such as pipes, ducts, fans, or pumps to transfer the heat that the house collects on sunny days. Instead, a passive solar home relies on properly oriented windows. Since the sun shines from the south in North America, passive solar homes are built so that most of the windows face south. They have very few or no windows on the north side. A passive solar home converts solar energy into heat just as a closed car does. Sunlight passes through a home's windows and is absorbed in the walls and floors. To control the amount of heat in a passive solar house, the doors and windows are closed or opened to keep heated air in or to let it out. At night, special heavy curtains or shades are pulled over the windows to keep the daytime beat inside the house. In the summer, awnings or roof overhangs help to cool the house by shading the windows from the high summer sun. Heating a house by warming the walls or floors is more comfortable than heating the air inside a house. It is not so drafty. And passive buildings are quiet, peaceful places to live. A passive solar home can get 50 to 80 percent of the heat it needs from the sun. Many homeowners install equipment (such as fans to help circulate air) to get more out of their passive solar homes. When special equipment is added to a passive solar home, the result is called a hybrid system.
Active Solar Homes Unlike a passive solar home, an active solar home uses mechanical equipment, such as pumps and blowers, and an outside source of energy to help heat the house when solar energy is not enough. Active systems use special solar collectors that look like boxes covered with glass. Dark-colored metal plates inside the boxes absorb the sunlight and change it into heat. (Black absorbs sunlight more than any other color.)
Air or a liquid flows through the collectors and is warmed by this heat. The warmed air or liquid is then distributed to the rest of the house just as it would be with an ordinary furnace system. Solar collectors are usually placed high on roofs where they can collect the most sunlight. They are also put on the south side of the roof where no tall trees or tall buildings will shade them.
Storing Solar Heat The challenge confronting any solar heating system--whether passive, active, or hybrid--is heat storage. Solar heating systems must have some way to store the heat that is collected on sunny days to keep people warm at night or on cloudy days. In passive solar homes, heat is stored by using dense interior materials that retain heat well-masonry, adobe, concrete, stone, or water. These materials absorb surplus heat and radiate it back into the room after dark. Some passive homes have walls up to one foot thick. In active solar homes, heat may be stored in one of two ways--a large tank may store a hot liquid, or rock bins beneath a house may store hot air. Houses with active or passive solar heating systems may also have furnaces, wood-burning stoves, or another heat source to provide heat in case there is a long period of cold or cloudy weather. This is called a backup system.
4. Solar Hot Water Heating Solar energy is also used to heat water. Water heating is usually the second leading home energy expense, costing the average family over $400, a year. Depending on where you live, and how much hot water your family uses, a solar water heater can pay for itself in as little as five years. A wellmaintained system can last 15-20 years, longer than a conventional water heater. A solar water heater works in the same way as solar space heating. A solar collector is mounted on the roof, or in an area of direct sunlight. It collects sunlight and converts it to heat. When the collector becomes hot enough, a thermostat starts a pump. The pump circulates a fluid, called a heat transfer fluid, through the collector for heating. The heated fluid then goes to a storage tank where it heats water. The hot water may then be piped to a faucet or showerhead. Most solar water heaters that operate in winter use a heat transfer fluid, similar to antifreeze, that will not freeze when the weather turns cold. Today over 1.5 million homes in the U.S. use solar heaters to heat water for their homes or swimming pools.
5. Solar Electricity Besides heating homes and water, solar energy also can be used to produce electricity. Two ways to generate electricity from solar energy are photovoltaics and solar thermal systems.
Photovoltaic Electricity Photovoltaic comes from the words photo meaning "light" and volt, a measurement of electricity. Sometimes photovoltaic cells are called PV cells or solar cells for short. You are probably already familiar with solar cells. Solar-powered calculators, toys, and telephone call boxes all, use solar cells to convert light into electricity.
A photovoltaic cell is made of two thin slices of silicon sandwiched together and attached to metal wires. The top slice of silicon, called the N-layer, is very thin and has a chemical added to it that provides the layer with an excess of free electrons. The bottom slice, or P-layer, is much thicker and has a chemical added to it so that it has very few free electrons. When the two layers are placed together, an interesting thing happens-an electric field is produced that prevents the electrons from traveling from the top layer to the bottom layer. This one-way junction with its electric field becomes the central part of the PV cell. When the PV cell is exposed to sunlight, bundles of light energy known as photons can knock some of the electrons from the bottom P-layer out of their orbits through the electric field set up at the P-N junction and into the N-layer. The N-layer, with its abundance of electrons, develops an excess of negatively charged electrons. This excess of electrons produces an electric force to push the additional electrons away. These excess electrons are pushed into the metal wire back to the bottom P-layer, which has lost some of its electrons. This electrical current will continue flowing as long as radiant energy in the form of light strikes the cell and the pathway, or circuit, remains closed. Current PV cell technology is not very efficient. Today's PV cells convert only about 10 to 14 percent of the radiant energy into electrical energy. Fossil fuel plants, on the other hand, convert from 30-40 percent of their fuel's chemical energy into electrical energy. The cost per kilowatt-hour to produce electricity from PV cells is presently three to four times as expensive as from conventional sources. However, PV cells make sense for many uses today, such as providing power in remote areas or other areas where electricity is difficult to provide. Scientists are researching ways to improve PV cell technology to make it more competitive with conventional sources.
Solar Thermal Electricity Like solar cells, solar thermal systems use solar energy to make electricity. But as the name suggests, solar thermal systems use the sun's heat to do it. Most solar thermal systems use solar collectors with mirrored surfaces to concentrate sunlight onto a receiver that heats a liquid. The super-heated liquid is used to make steam that drives a turbine to produce electricity in the same way that coal, oil, or nuclear power plants do. Solar thermal systems may be one of three types: central receiver, dish, or trough. A central receiver system uses large mirrors on top of a high tower to reflect sunlight onto a receiver. This system has been dubbed a "solar power tower." Another system uses a dish-shaped solar collector to collect sunlight. This system resembles a television satellite dish. A third system uses mirrored troughs to collect sunlight. Until recently, trough systems seemed the most promising. The world's first solar electric plant used mirrored troughs. LUZ, as the plant was called, was perfectly situated in the sunny Mojave desert of California. LUZ was the only solar plant to generate electricity economically. Dollar for dollar, it had always been cheaper to use conventional sources of energy (coal, oil, nuclear) to generate electricity. But the LUZ solar plant turned that around, producing electricity as cheaply as many new coal plants, and with no hidden pollution costs. The future looked bright for this pioneering solar plant and then the dream cracked. LUZ closed its doors at the end of 1992 because of a drop in oil prices and an over-budget construction project at LUZ's home-base. LUZ may be gone, but most solar energy engineers believe solar power towers will be ready to take the place of trough systems very soon.
6. Solar Energy and the Environment
In the 1970s, the push for renewable energy sources was driven by oil shortages and price increases. Today, the push for renewable energy sources is driven by a renewed concern for the environment. Solar energy is the prototype of an environmentally friendly energy source. It consumes none of our precious energy resources, makes no contribution to air, water, or noise pollution, does not pose a health hazard, and contributes no harmful waste products to the environment. There are other advantages too. Solar energy cannot be embargoed or controlled by any one nation. And it will not run out until the sun goes out.
Solar System Descriptions In today's climate of growing energy needs and increasing environmental concern, alternatives to the use of non-renewable and polluting fossil fuels have to be investigated. One such alternative is solar energy. Solar energy is quite simply the energy produced directly by the sun and collected elsewhere, normally the Earth. The sun creates its energy through a thermonuclear process that converts about 650,000,0001 tons of hydrogen to helium every second. The process creates heat and electromagnetic radiation. The heat remains in the sun and is instrumental in maintaining the thermonuclear reaction. The electromagnetic radiation (including visible light, infra-red light, and ultraviolet radiation) streams out into space in all directions. Only a very small fraction of the total radiation produced reaches the Earth. The radiation that does reach the Earth is the indirect source of nearly every type of energy used today. The exceptions are geothermal energy, and nuclear fission and fusion. Even fossil fuels owe their origins to the sun; they were once living plants and animals whose life was dependent upon the sun. Much of the world's required energy can be supplied directly by solar power. More still can be provided indirectly. The practicality of doing so will be examined, as well as the benefits and drawbacks. In addition, the uses solar energy is currently applied to will be noted. Due to the nature of solar energy, two components are required to have a functional solar energy generator. These two components are a collector and a storage unit. The collector simply collects the radiation that falls on it and converts a fraction of it to other forms of energy (either electricity and heat or heat alone). The storage unit is required because of the non-constant nature of solar energy; at certain times only a very small amount of radiation will be received. At night or during heavy cloudcover, for example, the amount of energy produced by the collector will be quite small. The storage unit can hold the excess energy produced during the periods of maximum productivity, and release it when the productivity drops. In practice, a backup power supply is usually added, too, for the situations when the amount of energy required is greater than both what is being produced and what is stored in the container. Methods of collecting and storing solar energy vary depending on the uses planned for the solar generator. In general, there are three types of collectors and many forms of storage units. The three types of collectors are flat-plate collectors, focusing collectors, and passive collectors. Flat-plate collectors are the more commonly used type of collector today. They are arrays of solar panels arranged in a simple plane. They can be of nearly any size, and have an output that is directly related to a few variables including size, facing, and cleanliness. These variables all affect the amount of radiation that falls on the collector. Often these collector panels have automated machinery that keeps them facing the sun. The additional energy they take in due to the correction of facing more than compensates for the energy needed to drive the extra machinery
.
Focusing collectors are essentially flat-plane collectors with optical devices arranged to maximize the radiation falling on the focus of the collector. These are currently used only in a few scattered areas. Solar furnaces are examples of this type of collector. Although they can produce far greater amounts of energy at a single point than the flat-plane collectors can, they lose some of the radiation that the flat-plane panels do not. Radiation reflected off the ground will be used by flat-plane panels but usually will be ignored by focusing collectors (in snow covered regions, this reflected radiation can be significant). One other problem with focusing collectors in general is due to temperature. The fragile silicon components that absorb the incoming radiation lose efficiency at high temperatures, and if they get too hot they can even be permanently damaged. The focusing collectors by their very nature can create much higher temperatures and need more safeguards to protect their silicon components .
Passive collectors are completely different from the other two types of collectors. The passive collectors absorb radiation and convert it to heat naturally, without being designed and built to do so. All objects have this property to some extent, but only some objects (like walls) will be able to produce enough heat to make it worthwhile. Often their natural ability to convert radiation to heat is enhanced in some way or another (by being painted black, for example) and a system for transferring the heat to a different location is generally added.
People use energy for many things, but a few general tasks consume most of the energy. These tasks include transportation, heating, cooling, and the generation of electricity. Solar energy can be applied to all four of these tasks with different levels of success. Heating is the business for which solar energy is best suited. Solar heating requires almost no energy transformation, so it has a very high efficiency. Heat energy can be stored in a liquid, such as water, or in a packed bed. A packed bed is a container filled with small objects that can hold heat (such as stones) with air space between them. Heat energy is also often stored in phase-changer or heat-offusion units. These devices will utilize a chemical that changes phase from solid to liquid at a temperature that can be produced by the solar collector. The energy of the collector is used to change the chemical to its liquid phase, and is as a result stored in the chemical itself. It can be tapped later by allowing the chemical to revert to its solid form. Solar energy is frequently used in residential homes to heat water. This is an easy application, as the desired end result (hot water) is the storage facility. A hot water tank is filled with hot water during the day, and drained as needed. This application is a very simple adjustment from the normal fossil fuel water heaters. Swimming pools are often heated by solar power. Sometimes the pool itself functions as the storage unit, and sometimes a packed bed is added to store the heat. Whether or not a packed bed is used, some method of keeping the pool's heat for longer than normal periods (like a cover) is generally employed to help keep the water at a warm temperature when it is not in use. Solar energy is often used to directly heat a house or building. Heating a building requires much more energy than heating a building's water, so much larger panels are necessary. Generally a building that is heated by solar power will have its water heated by solar power as well. The type of storage facility most often used for such large solar heaters is the heat-of-fusion storage unit, but other kinds (such as the packed bed or hot water tank) can be used as well. This application of solar power is less common than the two mentioned above, because of the cost of the large panels and storage system required to make it work. Often if an entire building is heated by solar power, passive collectors are used in addition to one of the other two types. Passive collectors will generally be an integral part of the building itself, so buildings taking advantage of passive collectors must be created with solar heating in mind. These passive collectors can take a few different forms. The most basic type is the incidental heat trap. The idea behind the heat trap is fairly simple. Allow the maximum amount of light possible inside through a window (The window should be facing towards the equator for this to be achieved) and allow it to fall on a floor made of stone or another heat holding material. During the day, the area will stay cool as the floor absorbs most of the heat, and at night, the area will stay warm as the stone reemits the heat it absorbed during the day.
Another major form of passive collector is thermosyphoning walls and/or roof. With this passive collector, the heat normally absorbed and wasted in the walls and roof is re-routed into the area that needs to be heated. The last major form of passive collector is the solar pond. This is very similar to the solar heated pool described above, but the emphasis is different. With swimming pools, the desired result is a warm pool. With the solar pond, the whole purpose of the pond is to serve as an energy regulator for a building. The pond is placed either adjacent to or on the building, and it will absorb solar energy and convert it to heat during the day. This heat can be taken into the building, or if the building has more than enough heat already, heat can be dumped from the building into the pond. Solar energy can be used for other things besides heating. It may seem strange, but one of the most common uses of solar energy today is cooling. Solar cooling is far more expensive than solar heating, so it is almost never seen in private homes. Solar energy is used to cool things by phase changing a liquid to gas through heat, and then forcing the gas into a lower pressure chamber. The temperature of a gas is related to the pressure containing it, and all other things being held equal, the same gas under a lower pressure will have a lower temperature. This cool gas will be used to absorb heat from the area of interest and then be forced into a region of higher pressure where the excess heat will be lost to the outside world. The net effect is that of a pump moving heat from one area into another, and the first is accordingly cooled. Besides being used for heating and cooling, solar energy can be directly converted to electricity. Most of our tools are designed to be driven by electricity, so if you can create electricity through solar power, you can run almost anything with solar power. The solar collectors that convert radiation into electricity can be either flat-plane collectors or focusing collectors, and the silicon components of these collectors are photovoltaic cells. Photovoltaic cells, by their very nature, convert radiation to electricity. This phenomenon has been known for well over half a century, but until recently the amounts of electricity generated were good for little more than measuring radiation intensity. Most of the photovoltaic cells on the market today operate at an efficiency of less than 15%; that is, of all the radiation that falls upon them, less than 15% of it is converted to electricity. The maximum theoretical efficiency for a photovoltaic cell is only 32.3%, but at this efficiency, solar electricity is very economical. Most of our other forms of electricity generation are at a lower efficiency than this. Unfortunately, reality still lags behind theory and a 15% efficiency is not usually considered economical by most power companies, even if it is fine for toys and pocket calculators. Hope for bulk solar electricity should not be abandoned, however, for recent scientific advances have created a solar cell with an efficiency of 28.2% efficiency in the laboratory. This type of cell has yet to be field tested. If it maintains its efficiency in the uncontrolled environment of the outside world, and if it does not have a tendency to break down, it will be economical for power companies to build solar power facilities after all. Of the main types of energy usage, the least suited to solar power is transportation. While large, relatively slow vehicles like ships could power themselves with large onboard solar panels, small constantly turning vehicles like cars could not. The only possible way a car could be completely solar powered would be through the use of battery that was charged by solar power at some stationary point and then later loaded into the car. Electric cars that are partially powered by solar energy are available now, but it is unlikely that solar power will provide the world's transportation costs in the near future. Solar power has two big advantages over fossil fuels. The first is in the fact that it is renewable; it is never going to run out. The second is its effect on the environment. While the burning of fossil fuels introduces many harmful pollutants into the atmosphere and contributes to environmental problems like global warming and acid rain, solar energy is completely non-polluting. While many acres of land must be destroyed to feed a fossil fuel energy plant its required fuel, the only land that must be destroyed for a solar energy plant is the land that it stands on. Indeed, if a solar energy system were incorporated into every business and dwelling, no land would have to be destroyed in the name of energy. This ability to decentralize solar energy is something that fossil fuel burning cannot match.
As the primary element of construction of solar panels, silicon, is the second most common element on the planet, there is very little environmental disturbance caused by the creation of solar panels. In fact, solar energy only causes environmental disruption if it is centralized and produced on a gigantic scale. Solar power certainly can be produced on a gigantic scale, too. Among the renewable resources, only in solar power do we find the potential for an energy source capable of supplying more energy than is used. Suppose that of the 4.5x10 17 kWh per annum that is used by the earth to evaporate water from the oceans we were to acquire just 0.1% or 4.5x10 14 kWh per annum. Dividing by the hours in the year gives a continuous yield of 2.90x1010 kW. This would supply 2.4 kW to 12.1 billion people. This translates to roughly the amount of energy used today by the average American available to over twelve billion people. Since this is greater than the estimated carrying capacity of the Earth, this would be enough energy to supply the entire planet regardless of the population. Unfortunately, at this scale, the production of solar energy would have some unpredictable negative environmental effects. If all the solar collectors were placed in one or just a few areas, they would probably have large effects on the local environment, and possibly have large effects on the world environment. Everything from changes in local rain conditions to another Ice Age has been predicted as a result of producing solar energy on this scale. The problem lies in the change of temperature and humidity near a solar panel; if the energy producing panels are kept non-centralized, they should not create the same local, mass temperature change that could have such bad effects on the environment. Of all the energy sources available, solar has perhaps the most promise. Numerically, it is capable of producing the raw power required to satisfy the entire planet's energy needs. Environmentally, it is one of the least destructive of all the sources of energy. Practically, it can be adjusted to power nearly everything except transportation with very little adjustment, and even transportation with some modest modifications to the current general system of travel. Clearly, solar energy is a resource of the future.
Chapter 3 RENEWABLE ENERGY POLICY OF BANGLADESH Introduction Energy is one of the basic ingredients required to alleviate poverty and socioeconomic evelopment. GOB has issued its Vision and Policy Statement in February 2000, to bring the entire country under electricity service by the year 2020 in phases, in line with the direction of the Article 16 of ‘The Constitution of the People’s Republic of Bangladesh,’ to remove the disparity in the standards of living between the urban and rural areas through rural electrification and development. The energy prospect is generally assessed on the basis of available commercial sources of energy i.e., fossil fuel like gas, coal, oil etc. Worldwide, there is a major transition underway in the energy sector. It is happening due to the following three major reasons: (i) A decline in fossil fuel availability, their predicted gradual extinction in the next few decades and the resultant price volatility due to demand-supply gap. (ii) The need to drastically cut global emissions for mitigating climate change (80% reduction by 2050). (iii) The need for energy security. In Bangladesh efficient utilization of renewable energy resources is yet to assume commercial dimensions and hence rational policy dissemination on renewable energy usage
is essential. The renewable energy includes solar, wind, biomass, hydro, geothermal, tidal wave etc. 1.2 Renewable energy in the form of traditional biomass is the main source of primary energy in the country comprising some 35-60% percent of total primary energy use. The size and economic potential of the renewable energy resources (e.g., solar photovoltaic, solar thermal power, wind power, biogas, etc.) in Bangladesh are yet to be determined and the capacity of renewable energy development is presently low. Although investment costs of renewables are generally higher compared to fossil fuel alternatives, this option becomes economically viable when all externalities (e.g. environmental cost, health hazards etc.) and lower operating cost are taken into consideration.
The major sources of renewable energy are: Solar Solar photovoltaic: Solar photovoltaic (PV) systems are in use throughout the country with over 200,000 household-level installations having capacity of about 12 MW (June 2008). Scaling-up of solar PV systems assisted by the development partners are being implemented through the Rural Electrification Board (REB), Local Government Engineering Department (LGED), Bangladesh Power Development Board (BPDB) and other agencies implementing solar energy program. Renewable Energy Research Centre of the University of Dhaka has installed a model 1.1kW grid connected photovoltaic system. There is a strong potential for solar energy within the country. Solar Thermal Power/Concentrating Solar Power (CSP): The technology involves harnessing solar radiation for generation of electricity through a number of steps finally generating mechanical energy to run a generator. This technology needs to be disseminated in the country to supplement the power supply. 1.3.2 Wind Energy: Wind Energy has also made some inroads but its potential is mainly limited to coastal areas, and offshore islands with strong wind regimes. These coastal settings afford good opportunities for wind-powered pumping and electricity generation. Presently there are 2 MW of installed wind turbines at Feni and Kutubdia. 1.3.3 Biomass: Bangladesh has strong potential for biomass gasification based electricity. More common biomass resources available in the country are rice husk, crop residue, wood, jute stick, animal waste, municipal waste, sugarcane bagasse etc. This technology can be disseminated on a larger scale for electricity generation. 1.3.4 Biogas: Biogas mainly from animal and municipal wastes may be one of the promising renewable energy resources for Bangladesh. Presently there are tens of thousands of households and village-level biogas plants in place throughout the country. It is a potential source to harness basic biogas technology for cooking, and rural and peri-urban electrification to provide electricity during periods of power shortfalls. 1.3.5 Hydro: Microhydro and minihydro have limited potential in Bangladesh, with the exception of Chittagong and the Chittagong Hill tracts. Hydropower assessments have identified some possible sites from 10 kW to 5 MW but no appreciable capacity has yet been installed. There is one hydro power plant at Kaptai established in the 1960s with installed capacity of 230 MW. 1.3.6 Other renewable energy sources include bio-fuels, gasohol, geothermal, river current, wave and tidal energy. Potentialities of these sources are yet to be explored.
Objectives The objectives of renewable energy policy are to:
(i)
Harness the potential of renewable energy resources and dissemination of renewable energy technologies in rural, peri-urban and urban areas; (ii) Enable, encourage and facilitate both public and private sector investment in renewable energy projects; (iii) Develop sustainable energy supplies to substitute indigenous non-renewable energy supplies; (iv) Scale up contributions of renewable energy to electricity production; (v) Scale up contributions of renewable energy both to electricity and to heat energy; (vi) Promote appropriate, efficient and environment friendly use of renewable energy; (vii) Train; facilitate the use of renewable energy at every level of energy usage. (viii) Create enabling environment and legal support to encourage the use of renewable energy. (ix) Promote development of local technology in the field of renewable energy. (x) Promote clean energy for CDM; and (xi) Policy sets targets for developing renewable energy resources to meet five percent of the total power demand by 2015 and ten percent by 2020.
Institutional Arrangements An independent institution, Sustainable Energy Development Agency (SEDA), shall be established under the Companies Act, 1994, as a focal point for sustainable energy development and promotion, ‘sustainable energy’ comprising renewable energy and energy efficiency. SEDA Board will comprise of representatives of stakeholders including business community, academics and/or representative from Bangladesh Solar Energy Society, NGOs, financial institutions and implementing agencies. The responsibilities of SEDA as a company shall be to: (i) Provide coordination of sustainable energy planning, including action plans linking together the activities of several agencies or organizations; (ii) Promote awareness of renewable energy and other clean energy technologies and integrate their development within overall national energy policy and development; (iii) Support demonstration of new technologies and new business models for renewable energy and other clean energy technologies; (iv) Support establishment of small and medium renewable energy enterprises and providers; (v) Enable systematic development of renewable energy projects and opportunities through energy audits; (vi) Create market opportunities and start-up business models for sustainable energy technologies in Bangladesh, such as energy services companies and rural energy providers; (vii) Develop financing mechanisms and facilities by using grant, subsidy and/or carbon/CDM fund for public and private sector investments in all forms of sustainable energy; (viii) Collect data and assess the renewable energy resource base, especially in the context of rural energy master plan; (ix) Provide fund for the development of standardized renewable energy configurations to meet common energy and power applications, such as solar, biogas and bio-diesel for mechanical irrigation and improved community practices for forest management and conversion and
use of fuel wood by using grant, subsidy and/or carbon/CDM fund;
(x)
Stimulate market development for sustainable energy technologies, such as improved cook stoves and household biogas digesters; (xi) Provide financial support in the research and development of renewable energy technology; (xii) Implement policies for mitigation of environmental issues arising out of use of Renewable energy; and (xiii) Solicit and processing of grid connected renewable energy projects. Power Division of the MPEMR or its assignee will facilitate the development of renewable energy until SEDA is formed. Overall policy formulation and development functions of renewable energy shall lie with the power Division of the MPEMR.
Resource, Technology and Program Development 1.
SEDA in conjunction with the Power Division of the MPEMR shall be responsible for determining the priorities for renewable energy technology development and program implementation.
2.
SEDA shall support capacity building, technology development, and market development sufficient to boost the share of electricity generated from renewable energy technologies. All power utilities, LGED and other agencies are to develop renewable energy development program for implementation throughout the country. Electricity generated from renewable energy projects, both in public and private sectors may be purchased by power utilities or any consumer through mutual agreement (up to 5 MW). Renewable energy project sponsors may use existing electricity transmission and distribution systems, if there is adequate capacity, to supply electricity to its customers through mutual agreement between the project sponsor and the owner of transmission/distribution facilities . The sponsor will require to pay a wheeling charge to the owner of
3. 4. 5.
transmission/distribution facilities. The wheeling charges shall be determined by BERC in consultation with GOB. 6. 7. 8.
9.
In addition to electricity generation, renewable energy for solar heating and biogas or other means like cooking, etc shall be developed. SEDA will encourage human resource development and local production of renewable energy equipment, facilitate and monitor quality of renewable energy equipment, and will assist to setup quality control laboratory to test the renewable energy equipment.
For large biomass electricity projects (i.e. greater than 1 MW) the project developer must demonstrate that the biomass is being sustainably harvested and that no adverse social impact will result from that development. Production and use of bio-fuels may be encouraged but it shall not jeopardize the existing crop and shall not be a replacement of existing crop.
Investment and Fiscal Incentives 1. 2. 3.
A renewable energy financing facility shall be established that is capable of accessing public, private, donor, carbon emission trading (CDM) and carbon funds and providing financing for enewable energy investments. Power Division, MOF and SEDA will formulate a detailed program for providing fiscal incentives including customs and VAT exemptions for import and domestic manufacture of sustainable energy equipment. In addition to commercial lending, a network of micro-credit support system will be established especially in rural and remote areas to provide financial support for purchases of renewable energy equipment.
4. 5. 6. 7. 8. 9. 10. 11.
GOB will facilitate investment in renewable energy and energy efficiency projects. SEDA, in co-operation with local government offices, will set up an outreach program to develop renewable energy programs. SEDA will consider providing subsidies to utilities for installation of solar, wind, biomass or any other renewable/clean energy projects. Private sector participation including joint venture initiatives in renewable energy development will be encouraged and promoted. GOB/SEDA may assist in locating the project(s) and also assist in acquiring land for renewable energy project(s). Renewable energy project investors both in public and private sectors shall be exempted from corporate income tax for a period of 15 years. Renewable energy project investors both in public and private sectors shall be allowed to get the fiscal incentives provided in (i) SRO.73Accelerated depreciation up to 80% may be allowed in the first year. An incentive tariff may be considered for electricity generated from renewable energy sources which may be 1.25 times the highest purchase price of electricity by the utility from private generators. To promote solar water heaters, rates of both electricity and gas may be refixed to discourage electricity and gas use for water heating.
Regulatory Policy 1. 2. 3.
Renewable energy project(s), to sale electricity from plants shall be required to get power generation license from BERC if the capacity of the project(s) is 5 MW or more. GOB and SEDA, in consultation with BERC will create a regulatory framework encouraging generation of electricity from renewable energy sources. BERC shall approve the energy tariff in consultation with GOB/SEDA as per the provision of the BERC Act 2003 if the capacity of renewable energy project(s) is 5 MW or more. Electricity distributors may offer “green energy” tariffs, which provide consumers an opportunity to co-finance through their electricity bills the development of new renewable energy sources.
Glossary of Abbreviations/ Acronyms/ Terms BERC Bangladesh Energy Regulatory Commission BPDB Bangladesh Power Development Board CDM Clean Development Mechanism GOB Government of the People’s Republic of Bangladesh LGED Local Government Engineering Department MOF Ministry of Finance MPEMR Ministry of Power, Energy and Mineral Resources NEP National Energy Policy RE Renewable Energy REB Rural Electrification Board SEDA Sustainable Energy Development Agency RETs Renewable Energy Technologies VAT Value Added Tax
Chapter 4 Energy Sources in Bangladesh
Definitions Non-Renewable Energy Non-renewable energy is energy that is generated from non-renewable material reserves. These nonrenewable resources are limited in supply, that is to say that to be non-renewable a resource has to have a reasonably finite amount available for economically feasible extraction. We usually consider a resource non-renewable if it will non regenerate rapidly enough to meet our needs. Oil and coal are examples of non-renewable energy. Like all other fossil fuels, these non-renewable energy sources are created deep within the Earth, and cannot be replaced rapidly enough to meet the needs of any advanced civilization. Effectively, once we run out, we run out. We'll see miniscule amounts of oil and coal deposits build up, but it won't be for millions of years, eons of time, before our reserves are replaced. Nonrenewable sources of energy are used once, and afterwards are gone forever.
Renewable Energy Renewable Energy is a term that refers to energy sources that are renewable in nature, meaning that more and more is continuously generated, and for all practical purposes, that are virtually limitless in supply. Energy from our sun is one such example. Technically, the sunlight will fade in about 5 billion years, but for all practical purposes and human timescales, we will consider this a continuous and infinite resource. The sun isn't going to burn out any time soon. Solar panels have arrays of solar cells with harvest sunlight and convert it into electricity. You can learn more about solar cell and solar panels in our primary solar panel information section. Other renewable energy sources include wind and geothermal power. Wind power is generated by placing large windmills in windy areas, usually at high altitude to be maximally effective. Wind power, like solar power, is clean, but is also plagued by cost of setup and cost per kilowatt. Wind power may be unreliable in certain areas where the wind isn't strong year-round. Geothermal energy, a form of energy generated from the tectonic pressures and movements that heat the earth's crust, is used to boil steam and generate electricity.
Non-Renewable Energy Background In 2005, Bangladesh’s real gross domestic product (GDP) grew at 5.4 percent, down somewhat from the 2004 growth rate of 6.3 percent. Economic forecasts are at 5.8 percent for 2006. Economic performance has been steady since 1990, with annual GDP growth averaging 5 percent. However, Bangladesh remains one of the world’s poorest and most densely populated countries, and faces a number of obstacles to further growth and development. Despite recent growth, Bangladesh faces numerous challenges. According to the International Monetary Fund (IMF), the country is hampered by weak institutions and inadequate infrastructure. Bangladesh remains dependent on foreign aid and worker remittances for a large percent of its economic activity. In 2004, the government of Bangladesh estimated that remittances from expatriates totaled $3.3 billion, or 6 percent of nominal GDP. The country also remains vulnerable to natural disasters such as cyclones, floods, and droughts. This is especially true in the agriculture sector, which employs about two-thirds of the labor force and accounts for 22 percent of GDP.
Bangladesh is a member of the South Asian Association for Regional Cooperation (SAARC), along with Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka. SAARC aims to promote regional economic cooperation as well as economic and social development in South Asia. In 2004, the seven SAARC members agreed to create a South Asian Free Trade Area (SAFTA), which came into force on 1 January 2006. SAFTA aims to reduce tariffs and other trade barriers between the seven member countries.
Oil According to Oil & Gas Journal (OGJ), Bangladesh has 28 million barrels of proven oil reserves as of January 2006, down from 56 million barrels in 2005. The country produced an estimated 4,000 barrels per day (bbl/d) of oil in 2005, flat from the previous year. Bangladesh’s relatively low level of domestic reserves and production capacity make it a net oil importer, as the country consumed an estimated 91,000 bbl/d of oil in 2005.
Exploration and Production To date oil exploration has been rather unsuccessful in Bangladesh, with most companies choosing to focus instead on the country’s plentiful natural gas reserves. Exploration and production activities are primarily carried out by the Bangladesh Petroleum Exploration and Production Company (BAPEX), a
subsidiary of the state-owned Bangladesh Oil, Gas & Mineral Corporation (Petrobangla). However, the country has also initiated several Production Sharing Contracts (PSCs) with foreign oil companies and has employed tax incentives to attract foreign company involvement. In 1993, after the formation of a new National Energy policy, the government of Bangladesh divided its territory and offshore sites into 23 blocks and opened them to foreign bidding for oil and gas exploration. During the First Bidding Round in 1993, eight blocks were awarded to four companies through PSCs. In 1997 during the Second Bidding Round, three PSCs were awarded covering four additional blocks. The government planned to hold a third round of bidding focusing on the offshore Bay of Bengal region in 2006, but it has so far been delayed. Before new bidding is opened, the government will complete a geological and seismic survey to identify potential exploration sites. Bangladesh must also accurately mark its deep sea territory and settle ongoing maritime border disputes with India and Myanmar.
Refining/Downstream According to OGJ, Bangladesh has 33,000-bbl/d of crude oil refining capacity at Eastern Refinery Ltd.’s (ERL) facility at Chittagong. The ERL complex is a subsidiary of the state-owned Bangladesh Petroleum Corporation (BPC).
Natural Gas Natural gas reserve estimates vary widely for Bangladesh. Oil & Gas Journal (OGJ) reported that Bangladesh had 5 trillion cubic feet (Tcf) of proven natural gas reserves as of January 2006, down significantly from OGJ’s January 2005 estimate of 10.6 Tcf. It is not clear why the large downgrade of Bangladesh’s natural gas reserves occurred. In mid-2004, estimates from state-owned Petrobangla put net proven reserves at 15.3 Tcf. Bangladesh’s Ministry of Finance estimated in 2004 that the country holds 28.4 Tcf of total gas reserves, of which 20.5 Tcf is recoverable. In June 2001, the U.S. Geological Survey estimated that Bangladesh contains 32.1 Tcf of additional “undiscovered reserves.” While estimates of the country’s reserves vary, natural gas is Bangladesh’s only significant source of commercial energy. The government of Bangladesh estimates that natural gas accounts for 80 percent of the country’s commercial energy consumption. In 2004, Bangaladesh produced 463 billion cubic feet (Bcf) of natural gas, up from 429 Bcf in 2003 and more than doubling the 1994 level. Despite increasing production levels, Bangladesh has never been a net exporter of natural gas. Given the uncertain size of the country’s natural gas reserves, the government has been reluctant to export natural gas and has instead focused on meeting current and future domestic energy needs.
Exploration and Production Natural gas exploration and production is dominated by three state-owned companies, all of which are subsidiaries of Petrobangla. Bangladesh’s largest gas production company, Bangladesh Gas Fields Company Ltd. (BGFCL), operates the Sylhet, Kailashtila MSTE, Kailashtia, Rashidpur, and Beanibazar gas fields. From these five fields, BGFCL produces 810 million cubic feet per day (Mmcf/d), or roughly half of the country’s total natural gas production. The Sylhet Gas Field Company Ltd. (SGFCL) is Bangladesh’s second largest production company, producing 162 Mmcf/d of natural gas. SGFCL operates the Sylhet, Kailashtila MSTE, Kailashtia, Rashidpur, and Beanibazar gas fields. The third state-owned company involved in natural gas production and exploration is BAPEX, which produces about 58 Mmcf/d of natural gas from the Salda and Fenchuganj fields. To encourage natural gas exploration, the government opened the natural gas sector to foreign investment in 1993, after initiating the First Bidding Round of Production Sharing Contracts. Foreign companies today produce 501 Mmcf/d of natural gas from four gas fields. The leading foreign producer is Chevron, which produces 331 Mmcf/d from the Jalalabad and Moulavibazar fields. Chevron also expects to begin producing an estimated 300 Mmcf/d of natural gas from the Bibiana field in October 2006. The UK’s Cairn Energy is the second largest foreign natural gas production
company, producing 146 Mmcf/d of natural gas from Bangladesh’s lone offshore gas field at Sangu. Canada’s Niko Resources has been involved in disputes with the government after two blowouts that occurred in 2005 at the company’s Chattak (formerly known as Tengratila) gas field.
Natural Gas Production in Bangladesh, 1994-2004 There are several other fields that may prove to hold additional natural gas resources. Petrobangla estimates that the Bibiana field, currently operated by Chevron, may contain as much as 2.4 Tcf in recoverable natural gas reserves. Offshore natural gas fields also present large possible reserves, although minimal offshore exploration has occurred to date due to lingering border disputes with India and Myanmar.
Coal Bangladesh has small coal reserves, and has consumed little coal in the past. Bangladesh began commercial coal production in April 2003 with the opening of the Barapukuria Coal Mine, which is expected to produce one million short tons of coal per year (Mmst/y), principally for electricity generation. This mine is being used to fuel the 250-MW Barapukuria Coal-Fired Power Plant in
Parbotipur, which began commercial operation in January 2006. Another possible coal mining project at Khalashpir is under consideration as well. Despite Bangladesh’s small reserves, the government has recently promoted the development of coal to ease its reliance on natural gas for power generation. Bangladesh’s coal reserves have so far not been developed, mainly owing to a lack of domestic financing. To attract investment, the government has opened the coal sector to foreign bidding. Although estimates vary, Bangladesh’s Energy Ministry judges that the country has up to 2.7 billion short tons of high-quality coal reserves. According to the latest Energy Information Administration (EIA) figures, in 2004 Bangladesh has no domestic coal reserves or production. The government is currently crafting a new national coal policy that will govern foreign involvement in Bangladesh’s coal sector. Some analysts anticipate the new coal policy will hike the royalty rate on coal projects from 6 percent to 16 percent and place limits on coal exports from the country, among other guidelines. In July 2005, UK-based Asia Energy Corp. (AEC) submitted a proposal to develop a coal mine in Bangladesh’s Phulbari region. According to a Scheme of Development and Feasibility Study submitted to the government, AEC declares that the Phulbari site contains an estimated 572 million short tons of recoverable coal reserves. The initial investment in the project would be $1.4 billion, and the open-pit mine is expected to produce 15 Mmst/y of coal to fuel a planned 500-megawatt power station. AEC is awaiting formal approval from the government, which has declared that it will not approve any new coal development projects until its new coal policy is enacted. AEC also faces a number of other obstacles in gaining approval for the project. According to the Feasibility Study submitted by Asia Energy, up to 40,000 people would gradually be relocated away from the Phulbari area that currently live on or near the planned mining locations.
Renewable Energy Back ground A transition to renewable energy is inevitable, not because fossil fuel supplies will run out ,large reserves of oil, coal, and gas remain in the world, but because the costs and risks of using these supplies will continue to increase relative to renewable energy. Costs will increase as the environmental impacts of fossil fuel use are increasingly incorporated into the costs of energy and as the cheapest reserves are depleted”.
Solar Energy Bangladesh is situated between 20.30 - 26.38 degrees north latitude and 88.04 - 92.44 degrees east which is an ideal location for solar energy utilization. Daily average solar radiation varies between 4 to 6.5 kWh per square meter. Maximum amount of radiation is available on the month of March-April and minimum on December-January. Different R&D Organizations, Institutes and Universities are collecting solar insolation at different parts of Bangladesh. Some of them are presented in this chapter. Available Solar Insolation Data At present, solar insolation data can be found from the following sources: Renewable Energy Research Centre (RERC), Dhaka University (DU) is the only source which has got long-term measured data of Dhaka city in Bangladesh [UNESCAP 2000]. The published data are average of results of hourly measurements of over three years global (G) and diffuse (D) radiation with Eppley Precision Pyrometer. Bangladesh Meteorological Department has 34 sunshine recording stations situated generally in towns and cities. Department of Mechanical Engineering, Bangladesh University of Engineering (BUET) and Technology, has also got time series data of Dhaka city. Apart from the above-mentioned sources, few other organizations or institutes have also measured time series of global radiation, direct or beam radiation, diffuse radiation, sunshine hours and
temperatures of different parts of the country. But for meticulous estimation and simulation of different solar energy pplications several other parameters are required which are not available at the moment. Monthly Global Solar Insolation at different cities of Bangladesh and Daily Average Bright Sunshine hour at Dhaka city are presented in Tables
Wind Energy The Bangladesh Meteorological department has wind speed measuring stations in towns and cities . Data from earlier measurements and analysis of upper air data by CWET India show that wind energy resource of Bangladesh is not good enough (>7 m/s) for grid connected wind parks [GEF 2001]. Wind data from Bangladesh Meteorological Department and different previous and ongoing wind resource assessment projects are briefly described in the subsequent sections.
Wind Data From Bangladesh Meteorological Department Most of the previous wind speed data in Bangladesh is available from the Bangladesh Meteorological Department. Average values calculated from such wind data during 1961 to 1993 are presented in Table Some of the meteorological stations have automatic data logging systems which record windspeed data onto paper rolls but rest are recorded by office stuff. These are collected and set to the Headquarters in Dhaka where they are entered on computer and made available at an agreed cost to interested parties in addition to their being used for whether forecasting purposes. From experience reported by those interested in wind energy in measurements at low heights and relatively inaccurate instruments. Bangladesh Centre for Advanced Studies (BCAS) obtained and reviewed Bangladesh Meteorological Department records with a view to establishing the prospects for wind energy and the following information about the wind climate in Bangladesh had been found: • • • • •
Wind speeds at most Met Office stations appear to be low, with typical annual mean wind speeds of 2 to 4 knots or 1 to 2 m/s, at heights between 5 to 10 meter above ground level. Wind speeds appear to be higher in the east of the country than the west. Wind speeds in the coastal areas appear to be higher than inland. Wind speed exhibits a strong seasonal cycle, lowest in the winter and higher in the summer. Wind speed exhibits a diurnal cycle, generally peaking at noon and weakest at night.
Seven Wind measuring stations were located at – 1. Patenga 2. Cox’s Bazar 3. Kutubdia 4. Teknaf
5. Noakhali 6. Kuakata and 7. Char Fassion
The maximum velocity obtained at Tecknaf is 16 m/s and yearly average wind speed in 3.8 m/s.
Hydro Power
Bangladesh is a riverine country with three main rivers (1) Ganges (2) Brahmaputra and (3) Jamuna. About 1.4 trillion cubic meter (m³ ) of water flows through the country in an average water year. Numerous rivers flow across the country which are mostly tributaries of these main rivers which are shown in Figure 2.8. Out of these, 57 rivers are transboundary which originate from India and Myanmar. Apart from the south-eastern region, other parts of the country are mostly flat in nature. Major rivers of the country have high flow rate for about 5 to 6 months during monsoon season, which is substantially reduced during winter. More than 90% of Bangladesh’s rivers originates outside the country, due to which proper planning of water resource is difficult without neighboring countries’ cooperation. Downstream water sharing with India is a highly contentious issue in Bangladesh. Rainfall Pattern In Bangladesh, the annual average rainfall is about 2,300 mm, which varies from 1,200 mm in the northwest to 5,800 mm in the north-east. Most of the rainfall (80 %) occurs during the months of May/June to September/October. Types of Rivers In Bangladesh, there are three types of rivers – 1. Major and medium size perennial rivers with most of the catchment area outside the national border 2. Medium and small size seasonal internal rivers mainly tributaries and distributaries of the main rivers and 3. Small and medium both perennial and seasonal border rivers Medium and Large Hydro Potential At present only 230 MW of hydro power is utilized in Karnafuli Hydro Station, which the only hydro-electric power plant operated by Bangladesh Power Development Board (BPDB). BPDB is considering extension of Karnafuli Hydro Station to add another 100 MW capacity which will add energy marginally, but will be effective to operate it as a peaking power plant. The additional energy will be generated during the rainy season when most of the year water is spilled. Apart from Kaptai, two other prospective sites for hydro power generation at Sangu and Matamuhuri river are identified by BPDB. But no pre-feasibility study has been made so far. A brief description of these two sites is given below. Sangu Project This would be a new Project with an annual energy of about 300 GWh per year. For an installed capacity of 140 MW, the annual plant factor is 23%, and it is estimated that the plant would operate in peaking mode. However, this project needs a detailed environmental, social and economic study in the present day context. Matamuhuri Project The Matamuhuri development would be a new project of capacity 75 MW and an approximate average annual energy 200 GWh per year. Small Hydro Potential
Several attempts have been made in the past to find out the potential of small-hydro power generation which is believed to be more environment or ecology friendly in comparison to large hydro with dams. Some of the previous studies at different parts of the country are described in the following headings. plant. The finding of the committee is summarized in Table 4.1. Later in the month of April 1984 a group of Chinese experts visited Bangladesh and identified 12 prospective sites in the hilly areas of Bangladesh. Out of those 12 sites, Mahamaya Chara, near Mirersharai, close to DhakaChittagong highway was identified as best site for development of small hydro. Accordingly Bangladesh Water Development Board (BWDB) is considering to develop a multipurpose project at Mahamaya Chara. It has been found out from the feasibility study that generation of electricity is possible throughout the year except in the month of April and May and a small Hydro Power plant shall be installed at the down stream foot of the proposed dam for the generation of electricity.
There are also rivers which carry high discharges during the monsoon season and very small during the dry season. They have relatively high longitudinal slope across alluvial fans close to the Indian border. Most of the rivers have little flow in the winter months , and in dry years sometimes they dry out. The suitable scheme would include diversion structure across the river channel, diversion channel along the ridge and the powerhouse at a suitable location that offers sufficient head. 9 rivers are identified here.
Biomass Biomass in the most significant energy source in Bangladesh which accounts for 70% of the total final nergy consumption in Bangladesh [Islam 2000]. The main sources of biomass fuels are – 1. Trees (woodfuels, twigs, leaves, plant residues) 2. Agricultural Residues (paddy husk, bran, bagasse, jute stick etc.) and 3. Livestock (animal dung). Land use pattern and different biomass fuels of Bangladesh are described below in separate subsections. Land Use Pattern Approximate land use pattern of the country is Agricultural land : 64 % Forests : 18 % Human Settlement : 8 % Water and other : 10 % Different types of land pattern and forests with approximate percentage are shown in Table 5.1 and remote sensing image map of Bangladesh showing the land use patterns can be found at Figure
Woodfuel Total wood fuel consumption of the country is 8 million m3 where domestic cooking accounts for estimated 5.1 million m3 (63%) annually and the industrial and commercial sectors 2.9 million m3 annually(37%). Overall, tree and fuels provide 48%, agriculture residues 36%, dung 13% and Peat 3% [FMP, 1992]. Though it is commonly thought that reserve forests are the main source of wood fuel in the country, but from statistics it has been found that village forests are supplying 84% of total consumption which has been shown is Figure 5.2 along with other sources. At present there is acute shortages of wood fuel in Bangladesh, due to which poor people opt for other inferior type (not compact, difficult to handle) of biomasses like agricultural residues or animal dung. The future projection of demand and supply of wood fuel by Forestry Master Plan (FMP) 1993 is bleak which is shown in Table .
Forest Broadly Bangladesh’s forests can be divided into three types. (1) Mangrove forests in the coastal delta, 2) hill forests in the interior, and (3) a smaller area of inland sal (Shorea robusta) forest. Significant areas of both hill forest plantations and mangrove plantations have been established. A number of protected areas are under the jurisdiction of the Forestry Department, though most of these have been degraded by illegal logging and forest clearing. Studies using the latest remote sensing techniques have revealed the present land cover types and their variations over the years. As per these data, the evergreen forest cover in Bangladesh reduced from .4% to 3.2% between 1985/86 and 1992/93 [RWEDP 1997]. According to FAO Forestry Web Site (http://www.fao.org/forestry)- the deforestation rate of Bangladesh is about 1.3% i.e. 16,503 hector/year [FAO 2000]. Agricultural Residues Agricultural residues contribute significantly to the biomass sector of Bangladesh. Crop production generates considerable amounts of residues that can be used as energy source. Crop residues can be distinguished into field residues and process residues. Field residues are residues that are left in the field after harvesting. They are scattered over a wide area, and are generally used as fertilizer. Process residues are generated during crop processing, e.g. milling. They are available at a central location. Besides being as energy source, crop residues are used for several other purposes, such as fodder, raw manufacturing material. In some cases they are just burned as waste [RWEDP 2001]. In Table processed agricultural residues production from different principal corps in the year 1998 are shown.
Animal Dung Total live animals of Bangladesh in 2000 is estimated as 59.55 million heads (Table 5.5). Of the working cattle 92% was used for cultivation and 0.19% was for transportation [Islam 2000]. In Table 5.6, animal residues or manure are given in annual dry matter production in tons. Dry matter of animal manure is the matter left after the removal of moisture.
Municipal and Industrial Solid Wastes The main cities of Bangladesh are already over burdened with solid wastes from different sources. According to the World Banks study, the rural population generates only 0.15 kg per capita per day, while their urban counterparts generate 0.4 to 0.5 kg per capita per day [World Bank, 1998]. All city corporations, responsible for waste management, are unable to handle the solid waste properly. But attempts have been made to establish private community-based waste management systems through NGOs. In the capital city of the country – Dhaka, one of the most populated city in the world with about 10 million inhabitants and area of only 360 km2, waste disposal system has become one of the major civic project. It has been estimated by different sources that each day about 3000 to 5000 tons of solid waste materials are generated in the city. Recently, Waste Concern, NGO involved with waste management, has entered into a Memorandum of Understanding (MOU) with the Dhaka City Corporation under which eight new community-based composting plants are being established throughout the city. Waste Concern have demonstrated how creative ventures, in which nongovernment and private sector organizations support the work of waste disposal authorities, can tackle the serious problems of waste management and generate revenue for all those involved. Their innovative approach has been recognized internationally and they are requested to provide technical support in India and Palestine [Waste Concern 2001]. At present two projects are under active consideration of Ministry of Environment. Two foreign companies (US & Canadian) have submitted their proposal to convert waste into energy in Dhaka using "Plasma Technology". According to Waste Concern, a leading NGO involved in waste management in the country, conversion of waste to energy may not be financially viable as our waste has low calorific value and high moisture content. Moreover, our waste has 70-75% organic matter [Iftekhar Enayetullah & Maqsood Sinha 2001].
Geothermal Geothermal energy is the natural heat of the Earth. It is a renewable source of energy if the exploration process don’t hamper the ecosystem or emit greenhouse gases. For Electricity and Direct Use
Geothermal reservoirs that are close enough to the surface to be reached by drilling can occur in places where geologic processes have allowed magma to rise up through the crust, near to the surface, or where it flows out as lava. The crust of the Earth is made up of huge plates, which are in constant but very slow motion relative to one another. Magma can reach near the surface in three main geologic areas: 1. Where Earth's large oceanic and crustal plates collide and one slides beneath another, called a subduction zone The best example of these hot regions around plate margins is the Ring of Fire ñ the areas bordering the Pacific Ocean: the South American Andes, Central America, Mexico, the Cascade Range of the U.S. and Canada, the Aleutian Range of Alaska, the Kamchatka Peninsula of Russia, Japan, the Philippines, Indonesia and New Zealand. 2. Spreading centers, where these plates are sliding apart, (such as Iceland, the rift valleys of Africa, the mid-Atlantic Ridge and the Basin and Range Province in the U.S.) and 3. Places called hot spots-- fixed points in the mantle that continually produce magma to the surface. Because the plate is continually moving across the hot spot, strings of volcanoes are formed, such as the chain of Hawaiian Islands. There is a known hot salt water spring, known as Labanakhya, in Bangladesh at 5 kilometer to the north of Sitakunda (40 kilometer from Chittagong). Possibility of extracting energy from this site or any other unknown sites can be investigated by Satellite Remote Sensing or Physical Surveys.
Marine RETs Bangladesh has got 710 km long coastal belt along the Bay of Bengal. If the marine RETs become viable option in the future, then the country may harness energy from marine RETs. The main marine RETs are – 1. Tidal 2. Wave and 3. Oceanic Thermal Energy Conversion Tidal Tidal power utilizes the twice daily variation in sea level caused primarily by the gravitational effect of the Moon and, to a lesser extent the Sun on the world's oceans. The Earth's rotation is also a factor in the production of tides. The normal tidal head rise and fall in the coastal region of Bangladeshi is between 2 and 8 meters as shown in Table . This tidal range can easily be converted to pollution free clean renewable energy by using the simple low-cost technology of a “tidal wheel” in the sluice gates. The real benefits of this technology however are that it can be applied in a way that simultaneously enables the development of local infrastructure and various resource producing activities such as agriculture and aquaculture along with improved living conditions for the local people [Salequzzaman et. al. 2001]. A demonstration tidal power project is being planned in Sandwip, one of the coastal island of Bangladesh, by ISTP of Murdoch University, Australia. ISTP has developed a feasibility plan for rebuilding a recently damaged sluice gate with a trial paddle wheel [REFOCUS March 2001]. If become successful, the tidal project of Sandwip can be replicated in the other coastal areas and which will usher new light in the region.
Oceanic Thermal Energy Conversion (OTEC) Ocean Thermal Energy Conversion (OTEC) utilizes the temperature difference between the warm surface sea water and cold deep ocean water to generate electricity. For OTEC to produce a net output of energy, the temperature difference between the surface water and water at a depth of 1000m needs to be about 20째C [Australian RE Website]. From the atlas shown in Figure 7.3, it can be seen that for Bay of Bengal the temperature difference between surface and sub surface (1000m) sea water is between 20 to 22째C. So, OTEC project is expected to be feasible in the Bay of Bengal in the future when the technology will be mature and cost of the system will go down.
Chapter 5
Solar Energy Solar Energy Application : A necessity for Bangladesh for Bangladesh Energy issue has become a global concern. Like other countries, Bangladesh also may not find immediate and easy solution to the energy problem. Moreover, with the passage of time the demand for energy in Bangladesh will increase further. From the past experience it appears that there is prevalence of huge gap between demand and supply. Striving to remove this demand and supply gap, Bangladesh has made significant progress in the renewable energy sector by introducing solar energy systems. Infrastructure Development Company Limited (IDCOL), Grameen Bank, BRAC and few other NGOs have taken remarkable steps forward in this regard. Grameen Shakti that has installed about 125,000 Solar Home Systems at rural level has opened our eyes. This energy technology might change the life style of the poor people. There are many solar power driven products available in the world market. Some of these are important for us. Submersible water solar pump can collect 310 litres of water per hour from 230 feet depth. A solar hot water tank can serve for 80 gallon storage. A solar Home System can feed the national power grid with the excess electricity it produces. Houses in California have installed solar panels on their roofs. Recreational vehicles like boats could run on customised solar power systems. UK is a pioneer of this system. A portable solar power system of 1500 watt capacity is also available which is capable of running a standard refrigerator, micro-oven, computer and office equipment. Sign lighting systems lights roads, bill boards and commercial sign boards. The remote off grid system of solar power has tremendous potential. Solar garden light, ground light, post light are usable everywhere and also in rainy conditions. The system like solar area lighting is perfect for park areas, open areas, beaches, pathways, boat docks, parking lots etc. Solar power security camera provides sustainable services from a distance. Portable power generator, laptop charger, solar power oven, solar power watch, solar radio, solar power mobile and solar balloon are interesting products. Research is going with a team of companies like General Motors and Ford to improve the solar car. Pool pumps and heaters that are run by solar power, makes people feel good to be making a difference in the condition of the environment, and it will save money, too. Solar Home Systems have mainly targeted the rural areas of Bangladesh so the range of products is limited. These can however be expanded to include the solar lantern, solar torch light, solar thermal heater, and solar mobile charger. Small shop owners at rural growth centers, mini poultry farm owners, country boat operators, and police and ansar-VDP forces, Union Parishad Chowkidars could be potential users of solar systems. In urban areas slum people may use these solar products to improve their living condition. Rickshaw puller may have the opportunity to use products like solar lantern in their rickshaws and other products for their households. In Bangladesh, building and houses located in all metropolitan areas could at least use some of the solar products in lightning their garden, boundary wall, gates and furnish security lights and water heating systems. RAJUK, CDA, KDA, RUK, city corporations, which have a role in approving architectural and structural plans may have a good opportunity to recommend solar energy systems. There are about 3000 growth centers in the country. If growth centers are lighted with solar applications by LGED it will have a tremendous effect in our agriculture, trade and commerce and thus economic growth. The government can also bring thousands of flood shelters cum schools, 465 Upazilla Chairman's houses, 490 Upazilla Teachers' Resource Centres, 5000 Union Parishad Buildings, 54 Primary Training Institutes (PTI) 3150 colleges, 18700 high schools and 9300 madrashahs under the solar power system. Moreover, 80,000 primary schools, 2.00 lakh mosques and few thousands rural health centres may have the opportunity to use this energy. Maintenance of solar system could be another opportunity of employment. Customised Technical education courses will build local capacity and help generate rural employment.
There are many islands in coastal areas and remote char areas in Bangladesh. At present, a few islands are using Solar Home Systems in households. The life of the people of Char areas may change dramatically change through solar power. Coastal areas will have similar opportunity. A lot of initiatives are taken around the world for using solar power. California's Governor has taken a billion dollar solar roof programme to produce 3000 megawatt solar electricity by 2017. European Community and country like U.K. and Germany are taking a lot of initiatives for solar energy. China, Japan and India are not very far from its expeditious implementation. Remarkable research and development (R&D) activities are taking places in many countries. Venture capitalists are investing money in solar technology and business. Nano technologies are coming up to meet the technical needs for sustainable solar power. Scientists, researchers and development agencies are working hard to face the challenges. Solar energy however will not be very competitive, in the economic sense, in a market dominated by fossil fuels. Despite market factors, solar industry needs government patronage and help to create the right momentum in solar market, and government grants are needed for research in solar technology. Many countries in the world have provided incentives to encourage people to use solar power. Unlike others, there are, of course, limitations in expanding these solar programmes in Bangladesh. Research & development is not very significant. Initial investment in solar systems is quite high. Moreover there is no complete manufacturing plant yet of solar systems in Bangladesh. These are expensive and susceptible to frequent change of technology. The private sector in Bangladesh may not be attracted enough to establish solar manufacturing plants. Public Private Partnership might provide a solution. We may also think about accessing funds from carbon trading etc. Despite the limitations, the objective conditions are favourable and ready for expansion of solar energy in Bangladesh. All we need are appropriate policy, planning and initiatives, together with Public Private Leadership.
How are solar panels made? Discover the process of making a solar panel Making solar panels is a delicate process, and it is for this reason that major solar advances did not come into play until the lattermost quarter of the last century, when advances in semiconductors and photovoltaic design allowed increasingly efficient and affordable solar cells to be developed.
Crystalline Silicon Solar Panels The creation of solar panels typically involves cutting crystalline silicon into tiny disks less than a centimeter thick. These thin, wafer-like disks are then carefully polished and treated to repair and gloss any damage from the slicing process. After polishing, dopants (materials added to alter an electrical charge in a semiconductor or photovoltaic solar cell) and metal conductors are spread across each disk. The conductors are aligned in a thin, grid-like matrix on the top of the solar panel, and are spread in a flat, thin sheet on the side facing the earth.
To protect the solar panels after processing, a thin layer of cover glass is then bonded to the top of the photovoltaic cell. After the bonding of protective glass, the nearly-finished panel is attached to a subtrate by an expensive, thermally conductive cement. The thermally conductive property of the cement keep the solar panel from becoming overheated; any leftover energy that the solar panel is unable to convert to electricity would otherwise overheat the unit and reduce the efficiency of the solar cells.
Despite these protective measures against the tendancy of solar panels to overheat, it is vital that when installing a solar panel, additional steps should be taken to ensure the solar panel is kept cool. Elevating the solar panel above ground (see solar panel mounts) to let the airflow underneath cool the device. Amorphous Silicon Solar Panels Amorphous silicon solar panels are a powerful, emerging line of photovoltaics, that differ in output, structure, and manufacture than traditional photovoltaics which use crystalline silicon. Amorphous silicon solar cells, or A-si cells, are developed in a continuous roll-to-roll process by vapor-depositing silicon alloys in multiple layers, with each extremely thin layer specializing in the absorption of different parts of the solar spectrum. The result is record-breaking efficiency and reduced materials cost (A-si solar cells are typically thinner than their crystalline counterparts). Some Amorphous Solar Panels also come with shade-resistant technology or multiple circuits within the cells, so that if an entire row of cells is subject to complete shading, the circuit won't be completely broken and some output can still be gained. This is especially useful when installing solar panels on a boat. The development process of Amorphous Silicon solar panels also renders them much less susceptible to breakage during transport or installation. This can help reduce the risk of damaging your significant investment in a photovoltaic system. Click here for more more information on amorphous silicon solar panels.
Concentrating Solar Power (CSP) Technologies Concentrating Solar Power (CSP) technologies use mirrors to concentrate (focus) the sun's light energy and convert it into heat to create steam to drive a turbine that generates electrical power. CSP technology utilizes focused sunlight. CSP plants generate electric power by using mirrors to concentrate (focus) the sun's energy and convert it into high-temperature heat. That heat is then channeled through a conventional generator. The plants consist of two parts: one that collects solar energy and converts it to heat, and another that converts the heat energy to electricity. Within the United States, CSP plants have been operating reliably for more than 15 years. All CSP technological approaches require large areas for solar radiation collection when used to produce electricity at commercial scale. CSP technology utilizes three alternative technological approaches: trough systems, power tower systems, and dish/engine systems.
 Trough systems use large, U-shaped (parabolic) reflectors (focusing mirrors) that have oil-filled pipes running along their center, or focal point, as shown in Figure 1. The mirrored reflectors are tilted toward the sun, and focus sunlight on the pipes to heat the oil inside to as much as 750°F. The hot oil is then used to boil water, which makes steam to run conventional steam turbines and generators.
Figure 1: Parabolic Schematic Diagram
Trough
System Figure 2: Parabolic trough system.
 Power tower systems also called central receivers, use many large, flat heliostats (mirrors) to track the sun and focus its rays onto a receiver. As shown in Figure 3, the receiver sits on top of a tall tower in which concentrated sunlight heats a fluid, such as molten salt, as hot as 1,050°F. The hot fluid can be used immediately to make steam for electricity generation or stored for later use. Molten salt retains heat efficiently, so it can be stored for days before being converted into electricity. That means electricity can be produced during periods of peak need on cloudy days or even several hours after sunset.
Figure 3: Power Tower Schematic Diagram Figure 4: Power tower system
Dish/engine systems use mirrored dishes (about 10 times larger than a backyard satellite dish) to focus and concentrate sunlight onto a receiver. As shown in Figure 5, the receiver is mounted at the focal point of the dish. To capture the maximum amount of solar energy, the dish assembly tracks the sun across the sky. The receiver is integrated into a highefficiency "external" combustion engine. The engine has thin tubes containing hydrogen or helium gas that run along the outside of the engine's four piston cylinders and open into the cylinders. As concentrated sunlight falls on the receiver, it heats the gas in the tubes to very high temperatures, which causes hot gas to expand inside the cylinders. The expanding gas drives the pistons. The pistons turn a crankshaft, which drives an electric generator. The
receiver, engine, and generator comprise a single, integrated assembly mounted at the focus of the mirrored dish.
Figure 6: Solar dish-engine system. Figure 5: Dish/engine System Schematic Diagram
Solar Photovoltaic Technologies Utility-scale solar photovoltaic technologies convert energy from sunlight directly into electricity, using large arrays of solar panels. Solar photovoltaic technologies convert solar energy into useful energy forms by directly absorbing solar photons—particles of light that act as individual units of energy—and either converting part of the energy to electricity (as in a photovoltaic (PV) cell) or storing part of the energy in a chemical reaction (as in the conversion of water to hydrogen and oxygen).
Solar Cells
Solar cells are devices that convert sunlight directly into electricity. Solar cells are made of layers of semiconductor materials similar to those used in computer chips. When sunlight is absorbed by these materials, the solar energy knocks electrons loose from their atoms, allowing the electrons to flow through the material to produce electricity..
Solar cell, module, and array.
Solar Arrays • Solar Furnace :Can achieve temperatures up to 3,000 degrees Celsius (huge array of mirrors)
Concentrated PV (CPV) Systems Concentrated PV (CPV) systems concentrate sunlight on solar cells, greatly increasing the efficiency of the cells. The PV cells in a CPV system are built into concentrating collectors that use a lens or mirrors to focus the sunlight onto the cells. CPV systems must track the sun to keep the light focused on the PV cells. The primary advantages of CPV systems are high efficiency, low system cost, and low
capital investment to facilitate rapid scale-up; the systems use less expensive semiconducting PV material to achieve a specified electrical output. Reliability, however, is an important technical challenge for this emerging technological approach; the systems generally require highly sophisticated tracking devices.
Concentrated PV (PCV) Collector
Mounts (Solar Panel Accessories) Solar Panel Mounts installation guide Mounts for your solar photovoltaic system can come in all shapes and sizes; some are stand-alone, others are designed for special situations, such as pole mounts designed to track the sun in the sky for optimal output. We will cover the most common types of solar panel mounts, and you will discover what mount or solar panel rack is best for your photovoltaic system. Considerations that will be addressed include size, affordablility, utility, and convienience.
Types of Solar Panel Mounts Solar Panel Mounts are available in three primary categories: flush mounts, roof/ground (or universal) mounts, and pole mounts. Each type of solar panel mount has its own merits and disadvantages, and if you are installing a solar panel mount you should weight in these factors when making your final descision. Flush Mounts Flush mounts are the cheapest and most simple solar panel mounting solution available, and are achieved by placing a metal end bracket on each side of the solar panel, elevating it several inches from the surface. Flush Mounts are typically used with small solar arrays on rooftops and RVs, because the structural design of a flush mount cannot support large solar panels. When installing a flush mount with your solar panel, be sure that you have ample clearance between the surface of the roof and the underside of your solar panel. This distance should be at a minimum of 2-4 inches, so that air can flow under the unit and keep it cool. This is vitally important for your flush mount system: if you do not allow clearance, your solar unit will rapidly overheat and the functional lifespan will be significantly reduced.
Although flush mounts are simple and cheap to install, they offer no flexibility in the orientation of your solar panel, and they can only support small photovoltaic units. To the left is a typical flush mount.
Roof-Ground (Universal) Mounts Roof-Ground solar panel mounts are typically used with larger solar panel systems, or in areas away from the city electric grid. Roof-Ground mounts are called by that name because they can be installed both on the ground and on rooftops. Roof-Ground mounts are typically constructed by a grid-like system of supports, and are typically bulky and unsightly, and many cities and neighborhoods have shamefully passed ordinances against them for asthetic reasons. You would be wise to consult with your residential director before installing a roof-ground solar panel mount.
There are many ways to install custom roof-ground mounts or increase the heights of your system by adding poles or concrete blocks to elevate your system above plants and vermin on the ground. Many Roof-ground mounts are adjustable, and if you change the tilt of your solar panel at the prescribed 1/4 year interval, your system will produce a little more power than a standard unit. Roof-ground systems are more expensive than flush mounts, and they may be difficult to install on rooftops due to heavy wind resistance or city ordinances, but they may be your only solution if you have a paticularly large solar panel system.
Pole Mounts Pole mounts are divided into 3 subcategories: top of pole mounts, side of pole mounts, and poll tracking mounts. These poll mounts are differentiated by how they are positioned on the pole. Pictured is a typical top-of-pole mount. Top of Pole Mounts are comprised of a metal rack and rail unit that is bolted to a large sleeve that rests on top of the pole. In order to install a top of pole mount, you will need to use an existing pole at least 3-8 inches wide with a concrete base, or construct one yourself. The mount simply slips over the top of the pole, and you can bolt (or weld) your solar panel unit into place. Large Top of pole mounts can encounter a substantial measure of wind resistance and can be very heavy, so you may need a small crane or several able-bodied men at hand in order to install a large top-of-pole system. Side of Pole Mounts are typically fastened and bolted to the side of telephone or utility poles. Side of pole solar panel mounts typically involve small solar panels, for larger units, it is reccomended that you use a top of pole solar panel mount. Tracking pole mounts are top of pole mounts with a special function - tracking pole mounts track the motion of the sun in the sky throughout the course of the day. This maximizes the operating efficiency of the solar panel unit.
Solar TECHNOLOGY Photovoltaics (PV) convert sunlight directly into electricity. Photons in sunlight interact with the outermost electrons of an atom. Photons striking the atoms of a semiconducting solar cell free it's electrons, creating an electric current. The Photovoltaic effect was first discovered in the 19th century, and was used by Bell Labs in 1954 to develop the first PV solar cell. PV found its first applications in space, providing electricity to satellites. These early PV cells were produced in small quantities from exotic materials. While early cells were inefficient, converting less than 1% of the incident sunlight into electricity, they quickly increased to 6% when researchers experimented with crystalline silicon, the principal component of sand. Current conversion efficiencies have surpassed 30% in the laboratory, and 15% in large-scale production. Two main types of silicon cells vie for market share: crystalline and thin-film. Crystalline silicon cells are produced by slowly extracting large crystals from a liquid silicon bath. These crystals are sliced into 1/100th-of-an-inch thick slices, or "wafers", which are processed into solar cells that are then connected and laminated into solar "modules." While this production process yields highly efficient (10-15%) cells, the production process is expensive. Thin-film silicon cells are produced by depositing vaporized silicon directly onto a glass or stainless steel substrate. While the efficiencies achieved are lower than with crystalline silicon, the production process is less expensive. Modules from crystalline cells have a lifetime of over twenty years. Thin-film modules will last at least ten years. Other PV technologies, such as Gallium-Arsenide or Cadmium Telluride, are also being used. These types are highly efficient, but more expensive at the present time.
PV is measured in units of "peak watts"(Wp). A peak watt figure refers to the power output of the module under "peak sun" conditions, considered to be 1000 Watts per square meter. "Sun hours," or "insolation," refers to how many hours of peak sun, on average, exist in different countries. North America averages 3 to 4 peak sun hours per day in summer while eqatorial regions can reach above 6 peak sunlight hours.
Solar Home System:
A standard small SHS can operate several lights, a black-and-white television, a radio or cassette player, and a small fan. A 35 Wp SHS provides enough power for four hours of lighting from four 7W lamps each evening, as well as several hours of television. "System Size" (20, 35, or 50Wp) determines the number of "light-hours" or "TV-hours" available. Solar Home Systems are 12-volt direct-current (DC) stand-alone systems which use PV to electrify small rural homes. Each SHS includes a PV module, a battery, a charge controller, wiring, fluorescent lights, and outlets for other appliances. Descriptions of the components follow:
Module: Solar modules for an SHS range between 20-60 Wp. They are mounted on a rooftop or atop a pole. Both crystalline and thin-film technologies are appropriate for an SHS, with price, weight, long-term guarantees and degradation being the determining factors.
Battery: An electrochemical storage battery is used to store the electricity converted by the solar module. During the day, electricity from the module charges the storage battery. During the evening, the battery is discharged to power lights and other applications. Batteries are typically 12-volt lead-acid batteries, ranging in capacity from 20-100 Amp-Hours (Ah). Batteries are typically sized to provide several days of electricity or "autonomy", in the event that overcast weather prevents recharging. Deep-cycle batteries are best for an SHS, as they are designed to operate over larger ranges of charge levels. While car batteries are only designed to be discharged 15% of their maximum charge, deep-cycle batteries can be discharged to 70-80% without incurring damage. Both deepcycle and automotive batteries are typically used, as they are readily available throughout the developing world. Car batteries have a 3-5 year lifetime; deep-cycle, both sealed and unsealed, can last 7-10 years.
Charge Controller: A charge controller is utilized to control the flow of electricity between the module, battery, and the loads. It prevents battery damage by ensuring that the battery is operating within its normal charge levels. If the charge level in the battery falls below a certain level, a "low voltage disconnect (LVD) will cut the current to the loads, to prevent further discharge. Likewise, it will also cut the current
from the module in cases of overcharging. Indicator lights on the controller display the relative state of charge of the battery.
Lights: Compact fluorescent lightbulbs as well as fluorescent tube lights are used for lighting. An SHS normally includes two to six lights. By utilizing efficient fluorescent lighting, an SHS can provide substantially higher lighting levels than would be possible with incandescent lighting. A 9 watt CFL provides equivalent illumination to a 60 watt incandescent bulb. Compact fluorescent lights have a 5 year lifetime; tubes have much shorter lives, but are cheaper and are more readily available in most developing countries.
Wiring & Mounting: An SHS also contains additional materials for mounting and connections. Metal frames are included to attach the PV Modules to a pole or roof. SHS components are connected by wires and contain switches for the lights. In some cases, wiring is housed inside conduit attached to interior walls. Solar thermal energy
Solar thermal system for water heating . Solar thermal energy (STE) is a technology for harnessing solar energy for thermal energy (heat). Solar thermal collectors are defined by the USA Energy Information Administration as low-, medium-, or high-temperature collectors. Low temperature collectors are flat plates generally used to heat swimming pools. Medium-temperature collectors are also usually flat plates but are used for creating hot water for residential and commercial use. High temperature collectors concentrate sunlight using mirrors or lenses and are generally used for electric power production. STE is different from photovoltaics, which convert solar energy directly into electricity. While only 600 megawatts of solar thermal power is up and running worldwide in October 2009 according to Dr David Mills of Ausra, another 400 megawatts is under construction and there are 14,000 megawatts of the more serious concentrating solar thermal (CST) projects being developed.
Low-temperature collectors Of the 21,000,000 square feet (2,000,000 m2) of solar thermal collectors produced in the United States in 2006, 16,000,000 square feet (1,500,000 m2) were of the low-temperature variety. Lowtemperature collectors are generally installed to heat swimming pools, although they can also be used for space heating. Collectors can use air or water as the medium to transfer the heat to their destination. Heating, cooling, and ventilation Main articles: HVAC, Solar space heating, Passive solar building design, Thermal mass, Trombe wall, Solar chimney, and Solar air conditioning
MIT's Solar House #1 built in 1939 used seasonal thermal storage for year round heating. In the United States, heating, ventilation, and air conditioning (HVAC) systems account for over 25 percent (4.75 EJ) of the energy used in commercial buildings and nearly half (10.1 EJ) of the energy used in residential buildings. Solar heating, cooling, and ventilation technologies can be used to offset a portion of this energy. Thermal mass materials store solar energy during the day and release this energy during cooler periods. Common thermal mass materials include stone, concrete, and water. The proportion and placement of thermal mass should consider several factors such as climate, daylighting, and shading
conditions. When properly incorporated, thermal mass can passively maintain comfortable temperatures while reducing energy consumption. A solar chimney (or thermal chimney) is a passive solar ventilation system composed of a hollow thermal mass connecting the interior and exterior of a building. As the chimney warms, the air inside is heated causing an updraft that pulls air through the building. These systems have been in use since Roman times and remain common in the Middle East. Solar space heating with air solar collectors is more popular in USA and Canada than heating with solar liquid collectors since most buildings already have a ventilation system for heating and cooling. The two main types of solar air panels are glazed and unglazed. Glazed Solar Collectors are designed primarily for space heating and they recirculate building air through a solar air panel where the air is heated and then directed back into the building. These solar space heating systems require at least two penetrations into the building and only perform when the air in the solar collector is warmer than the building room temperature. Most glazed collectors are used in the residential sector. Unglazed Solar Collectors are primarily used to heat ventilation air or ambient air and not building air. As these solar panels heat the fresh air for a building, they are ideally suited to commercial, industrial and institutional buildings with a high ventilation load. They only require one penetration into the building, or if existing fan inlets are used, then no additional penetrations are necessary. Heating ambient air allows solar energy to be utilized whenever the temperature in the collector is above ambient, not room temperature. This can provide twice the solar energy gain over space heating designs. The efficiency of a solar collector is highest when the temperature of the air entering the solar panel is equal ambient temperature. This occurs with solar heaters that draw outside air into the solar heater instead of room air. The transpired solar panel is a low cost and high performance unglazed solar panel and is building integrated. It is currently the most popular type of solar air heating in North America. A painted metal panel, with small holes spaced uniformly across the entire absorber, is the main feature of the transpired collector. Sunlight strikes the dark surface which absorbs the heat. Solar heat conducts from the surface to the thermal boundary layer of air 1 mm thick next to the plate. This boundary layer of air is drawn into a nearby hole before the heat can escape by convection, virtually eliminating heat loss off the surface of the plate. A Trombe wall is a passive solar heating and ventilation system consisting of an air channel sandwiched between a window and a sun-facing thermal mass. During the ventilation cycle, sunlight stores heat in the thermal mass and warms the air channel causing circulation through vents at the top and bottom of the wall. During the heating cycle the Trombe wall radiates stored heat. Solar roof ponds are unique solar heating and cooling systems developed by Harold Hay in the 1960s. A basic system consists of a roof-mounted water bladder with a movable insulating cover. This system can control heat exchange between interior and exterior environments by covering and uncovering the bladder between night and day. When heating is a concern the bladder is uncovered during the day allowing sunlight to warm the water bladder and store heat for evening use. When cooling is a concern the covered bladder draws heat from the building's interior during the day and is uncovered at night to radiate heat to the cooler atmosphere. The Skytherm house in Atascadero, California uses a prototype roof pond for heating and cooling. Active solar cooling can be achieved via absorption refrigeration cycles, desiccant cycles, and solar mechanical processes. In 1878, Auguste Mouchout pioneered solar cooling by making ice using a solar steam engine attached to a refrigeration device. [8] Thermal mass, smart windows and shading methods can also be used to provide cooling. The leaves of deciduous trees provide natural shade during the summer while the bare limbs allow light and warmth into a building during the winter. The water content of trees will also help moderate local temperatures.
Process heat Main articles: Solar pond, Salt evaporation pond, and Solar furnace
Solar Evaporation Ponds Solar process heating systems are designed to provide large quantities of hot water or space heating for nonresidential buildings. Evaporation ponds are shallow ponds that concentrate dissolved solids through evaporation. The use of evaporation ponds to obtain salt from sea water is one of the oldest applications of solar energy. Modern uses include concentrating brine solutions used in leach mining and removing dissolved solids from waste streams. Altogether, evaporation ponds represent one of the largest commercial applications of solar energy in use today. Unglazed transpired collectors (UTC) are perforated sun-facing walls used for preheating ventilation air. UTCs can raise the incoming air temperature up to 22 °C and deliver outlet temperatures of 4560 °C. The short payback period of transpired collectors (3 to 12 years) make them a more costeffective alternative to glazed collection systems. As of 2009, over 1500 systems with a combined collector area of 300,000 m² had been installed worldwide. Representatives include an 860 m² collector in Costa Rica used for drying coffee beans and a 1300 m² collector in Coimbatore, India used for drying marigolds. A food processing facility in Modesto, California uses parabolic troughs to produce steam used in the manufacturing process. The 5,000 m² collector area is expected to provide 4.3 GJ per year. Medium-temperature collectors solar water heating These collectors could be used to produce approximately 50% and more of the hot water needed for residential and commercial use in the United States. In the United States, a typical system costs $4000–$6000 and 30% of the system qualifies for a federal tax credit + additional state credit exists in about half of the states. With this incentive, the payback time for a typical household is four to nine years, depending on the state. Similar subsidies exist in parts of Europe. A crew of one solar plumber and two assistants with minimal training can install a system per day. Thermosiphon installation have negligible maintenance costs (costs rise if antifreeze and mains power are used for circulation) and in the US reduces a households' operating costs by $6 per person per month. Solar water heating can reduce CO2 emissions by 1 ton/year (if replacing natural gas for hot water heating) or 3 ton/year (if replacing electric hot water heating). Medium-temperature installations can use any of several designs: common designs are pressurized glycol, drain back, batch systems and newer low pressure freeze tolerant systems using polymer pipes containing water with photovoltaic pumping. European and International standards are being reviewed to accommodate innovations in design and operation of medium temperature collectors. Operational innovations include "permanently wetted collector" operation. This innovation reduces or even eliminates the occurrence of no-flow high temperature stresses called stagnation which would otherwise reduce the life expectancy of collectors.
Solar Drying Solar thermal energy can be very useful in drying wood for construction and wood fuels such as wood chips for combustion. Solar is also used for food products such as fruits, grains, and fish. Crop drying by solar means is environmentally friendly as well as cost effective while improving the quality. The less money it takes to make a product, the less it can be sold for, pleasing both the buyers and the sellers. Technologies in solar drying include ultra low cost pumped transpired plate air collectors based on black fabrics. Solar thermal energy is helpful in the process of drying products such as wood chips and other forms of biomass by raising the heat while allowing air to pass through and get rid of the moisture. Cooking Main article: Solar cooker The Solar Bowl above the Solar Kitchen in Auroville, India concentrates sunlight on a movable receiver to produce steam for cooking. Solar cookers use sunlight for cooking, drying and pasteurization. Solar cooking offsets fuel costs, reduces demand for fuel or firewood, and improves air quality by reducing or removing a source of smoke. The simplest type of solar cooker is the box cooker first built by Horace de Saussure in 1767. A basic box cooker consists of an insulated container with a transparent lid. These cookers can be used effectively with partially overcast skies and will typically reach temperatures of 50–100 °C. Concentrating solar cookers use reflectors to concentrate light on a cooking container. The most common reflector geometries are flat plate, disc and parabolic trough type. These designs cook faster and at higher temperatures (up to 350 °C) but require direct light to function properly. The Solar Kitchen in Auroville, India uses a unique concentrating technology known as the solar bowl. Contrary to conventional tracking reflector/fixed receiver systems, the solar bowl uses a fixed spherical reflector with a receiver which tracks the focus of light as the Sun moves across the sky. The solar bowl's receiver reaches temperature of 150 °C that is used to produce steam that helps cook 2,000 daily meals. Many other solar kitchens in India use another unique concentrating technology known as the Scheffler reflector. This technology was first developed by Wolfgang Scheffler in 1986. A Scheffler reflector is a parabolic dish that uses single axis tracking to follow the Sun's daily course. These reflectors have a flexible reflective surface that is able to change its curvature to adjust to seasonal variations in the incident angle of sunlight. Scheffler reflectors have the advantage of having a fixed focal point which improves the ease of cooking and are able to reach temperatures of 450-650 °C. Built in 1999, the world's largest Scheffler reflector system in Abu Road, Rajasthan India is capable of cooking up to 35,000 meals a day. By early 2008, over 2000 large cookers of the Scheffler design had been built worldwide.
Distillation Solar stills can be used to make drinking water in areas that clean water is not common. Solar distillation is necessary in these situations to provide people with purified water. Solar energy heats up the water in the still. The water then evaporates and condenses on the bottom of the covering glass.
High-temperature collectors The solar furnace at Odeillo in the French Pyrenees-Orientales can reach temperatures up to 3,800 degrees Celsius.
Concentrated solar power plant using parabolic trough design. Where temperatures below about 95°C are sufficient, as for space heating, flat-plate collectors of the nonconcentrating type are generally used. The fluid-filled pipes can reach temperatures of 150 to 220 degrees Celsius when the fluid is not circulating. This temperature is too low for efficient conversion to electricity. The efficiency of heat engines increases with the temperature of the heat source. To achieve this in solar thermal energy plants, solar radiation is concentrated by mirrors or lenses to obtain higher temperatures — a technique called Concentrated Solar Power (CSP). The practical effect of high efficiencies is to reduce the plant's collector size and total land use per unit power generated, reducing the environmental impacts of a power plant as well as its expense. As the temperature increases, different forms of conversion become practical. Up to 600°C, steam turbines, standard technology, have an efficiency up to 41%. Above this, gas turbines can be more efficient. Higher temperatures are problematic because different materials and techniques are needed. One proposal for very high temperatures is to use liquid fluoride salts operating between 700°C to 800°C, using multi-stage turbine systems to achieve 50% or more thermal efficiencies. The higher operating temperatures permit the plant to use higher-temperature dry heat exchangers for its thermal exhaust, reducing the plant's water use — critical in the deserts where large solar plants are practical. High temperatures also make heat storage more efficient, because more watt-hours are stored per unit of fluid. Since the CSP plant generates heat first of all, it can store the heat before conversion to electricity. With current technology, storage of heat is much cheaper and more efficient than storage of electricity. In this way, the CSP plant can produce electricity day and night. If the CSP site has predictable solar radiation, then the CSP plant becomes a reliable power plant. Reliability can further be improved by installing a back-up system that uses fossil energy. The back-up system can reuse most of the CSP plant, which decreases the cost of the back-up system. With reliability, unused desert, no pollution (so long as gas turbines aren't used) and no fuel costs, the obstacles for large deployment for CSP are cost, aesthetics, land use and similar factors for the necessary connecting high tension lines. Although only a small percentage of the desert is necessary to meet global electricity demand, still a large area must be covered with mirrors or lenses to obtain a significant amount of energy. An important way to decrease cost is the use of a simple design. System designs During the day the sun has different positions. If the mirrors or lenses do not move, then the focus of the mirrors or lenses changes. Therefore it seems unavoidable that there needs to be a tracking system that follows the position of the sun (for solar photovoltaics a solar tracker is only optional). The tracking system increases the cost and complexity. With this in mind, different designs can be distinguished in how they concentrate the light and track the position of the sun. Parabolic trough designs Main article: Parabolic trough
Sketch of a parabolic trough design. A change of position of the sun parallel to the receiver does not require adjustment of the mirrors. Parabolic trough power plants use a curved, mirrored trough which reflects the direct solar radiation onto a glass tube containing a fluid (also called a receiver, absorber or collector) running the length of the trough, positioned at the focal point of the reflectors. The trough is parabolic along one axis and linear in the orthogonal axis. For change of the daily position of the sun perpendicular to the receiver, the trough tilts east to west so that the direct radiation remains focused on the receiver. However, seasonal changes in the in angle of sunlight parallel to the trough does not require adjustment of the
mirrors, since the light is simply concentrated elsewhere on the receiver. Thus the trough design does not require tracking on a second axis. The receiver may be enclosed in a glass vacuum chamber. The vacuum significantly reduces convective heat loss. A fluid (also called heat transfer fluid) passes through the receiver and becomes very hot. Common fluids are synthetic oil, molten salt and pressurized steam. The fluid containing the heat is transported to a heat engine where about a third of the heat is converted to electricity. Andasol 1 in Gaudix, Spain uses the Parabolic Trough design which consists of long parallel rows of modular solar collectors. Tracking the sun from East to West by rotation on one axis, the high precision reflector panels concentrate the solar radiation coming directly from the sun onto an absorber pipe located along the focal line of the collector. A heat transfer medium, a synthetic oil like in car engines, is circulated through the absorber pipes at temperatures up to 400째C and generates live steam to drive the steam turbine generator of a conventional power block Concentrating solar power systems are a fast growing source of sustainable energy. Full-scale parabolic trough systems consist of many such troughs laid out in parallel over a large area of land. Since 1985 a solar thermal system using this principle has been in full operation in California in the United States. It is called the SEGS system.[23] Other CSP designs lack this kind of long experience and therefore it can currently be said that the parabolic trough design is the most thoroughly proven CSP technology. The Solar Energy Generating System (SEGS) is a collection of nine plants with a total capacity of 350MW. It is currently the largest operational solar system (both thermal and non-thermal). A newer plant is Nevada Solar One plant with a capacity of 64MW. Under construction are Andasol 1 and Andasol 2 in Spain with each site having a capacity of 50MW. Note however, that those plants have heat storage which requires a larger field of solar collectors relative to the size of the steam turbinegenerator to store heat and send heat to the steam turbine at the same time. Heat storage enables better utilization of the steam turbine. With day and some nighttime operation of the steam-turbine Andasol 1 at 50MW peak capacity produces more energy than Nevada Solar One at 64 MW peak capacity, due to the former plant's thermal energy storage system and larger solar field. 553MW new capacity is proposed in Mojave Solar Park, California. Furthermore, 59MW hybrid plant with heat storage is proposed near Barstow, California. Near Kuraymat in Egypt, some 40MW steam is used as input for a gas powered plant. Finally, 25MW steam input for a gas power plant in Hassi R'mel, Algeria. Power tower designs Main article: Solar power tower Solar Two. Flat mirrors focus the light on the top of the tower. The white surfaces below the receiver are used for calibrating the mirror positions. eSolar's 5 MW Sierra SunTower facility features arrays of heliostats (mirrors with sun-tracking motion) to concentrate sunlight on to a central receiver mounted at the top of a tower. Sierra SunTower is located in Lancaster, California. Power towers (also known as 'central tower' power plants or 'heliostat' power plants) capture and focus the sun's thermal energy with thousands of tracking mirrors (called heliostats) in roughly a two square mile field. A tower resides in the center of the heliostat field. The heliostats focus concentrated sunlight on a receiver which sits on top of the tower. Within the receiver the concentrated sunlight heats molten salt to over 1000 degrees Fahrenheit. The heated molten salt then flows into a thermal storage tank where it is stored, maintaining 98% thermal efficiency, and eventually pumped to a
steam generator. The steam drives a standard turbine to generate electricity. This process, also known as the "Rankine cycle" is similar to a standard coal-fired power plant, except it is fueled by clean and free solar energy. The advantage of this design above the parabolic trough design is the higher temperature. Thermal energy at higher temperatures can be converted to electricity more efficiently and can be more cheaply stored for later use. Furthermore, there is less need to flatten the ground area. In principle a power tower can be built on a hillside. Mirrors can be flat and plumbing is concentrated in the tower. The disadvantage is that each mirror must have its own dual-axis control, while in the parabolic trough design one axis can be shared for a large array of mirrors. Some or all of the following reads like a press release or commercial promotion, please assist by rewriting, simplifying, and trimming as needed SolarReserve, a Santa Monica, CA-based solar developer, utilizes this technology for the development of its concentrated solar thermal plants with storage. SolarReserve's power tower technology has been developed by one of the world's leading technology conglomerates, United Technologies Company (UTC). United Technologies' subsidiary, Rocketdyne, demonstrated the technology at the Solar One and Solar Two power tower plants in Southern California. United Technologies has granted SolarReserve the proprietary technology know-how and an exclusive worldwide license to develop power plants using this proven technology. In November 2009, SolarReserve, and a Madrid-based renewable energy developer, Preneal, received the key environmental permit that is necessary for the construction of their 50 megawatt solar plant in Spain. This project will generate more than 300,000 megawatt hours of electricity per year, or enough electricity to power almost 70,000 homes in the region. The Alcazar Solar Thermal Power Project will deploy innovative molten salt, concentrated solar power tower technology, which is exclusively licensed to SolarReserve by United Technologies Corporation (UTC). Unlike other forms of renewable energy technology, the power tower with energy storage allows for continuous generation of electricity, on-demand, day or night. In December 2009, SolarReserve announced two power contracts in the United States. The first was with Pacific Gas and Electric (PG&E) for the sale of electricity from SolarReserve's Solar Energy Project. The 150 megawatt solar energy project will be located 30 miles northwest of the city of Blythe in eastern Riverside County, California. When completed, SolarReserve's facility will supply approximately 450,000 megawatt hours annually of clean, reliable electricity—enough to power up to 68,000 homes during peak electricity periods—utilizing its innovative energy storage capabilities. The second power contract was a 25-year power purchase agreement with NV Energy for the sale of electricity from SolarReserve's Crescent Dunes Solar Energy Project. Developed and owned by SolarReserve's subsidiary, Solar Energy, LLC, the project will be located near the town of Tonopah in Nye County, Nevada. When completed, Tonopah Solar Energy's facility will supply approximately 480,000 megawatt hours annually. In June 2008, Solar, a Pasadena, CA-based company founded by Idealab CEO Bill Gross with funding from Google, announced a power purchase agreement (PPA) with the utility Southern California Edison to produce 245 megawatts of power. Additionally, in February 2009, eSolar announced it had licensed its technology to two development partners, the Princeton, N.J.-based NRG Energy, Inc., and the India-based ACME Group. In the deal with NRG, the companies announced plans to jointly build 500 megawatts of concentrating solar thermal plants throughout the United States. The target goal for the ACME Group was nearly double; ACME plans to start construction on its first eSolar power plant this year, and will build a total of 1 gigawatt over the next 10 years. Solar's proprietary sun-tracking software coordinates the movement of 24,000 1 meter-square mirrors per 1 tower using optical sensors to adjust and calibrate the mirrors in real time. This allows for a high density of reflective material which enables the development of modular concentrating solar thermal (CSP) power plants in 46 megawatt (MW) units on approximately π square mile parcels of land, resulting in a land-to-power ratio of 4 acres per 1 megawatt.
BrightSource Energy entered into a series of power purchase agreements with Pacific Gas and Electric Company in March 2008 for up to 900MW of electricity, the largest solar power commitment ever made by a utility.[ BrightSource is currently developing a number of solar power plants in Southern California, with construction of the first plant planned to start in 2009. In June 2008, BrightSource Energy dedicated its 4-6 MW Solar Energy Development Center (SEDC) in Israel's Negev Desert. The site, located in the Rotem Industrial Park, features more than 1,600 heliostats that track the sun and reflect light onto a 60 meter-high tower. The concentrated energy is then used to heat a boiler atop the tower to 550 degrees Celsius, generating superheated steam. A working tower power plant is PS10 in Spain with a capacity of 11MW. The 15MW Solar Tres plant with heat storage is under construction in Spain. In South Africa, a 100MW solar power plant is planned with 4000 to 5000 heliostat mirrors, each having an area of 140 m². A 10MW power plant in Cloncurry, Australia (with purified graphite as heat storage located on the tower directly by the receiver). Out of commission are the 10MW Solar One (later redeveloped and made into Solar Two) and the 2MW Themis plants. A cost/performance comparison between power tower and parabolic trough concentrators was made by the NREL which estimated that by 2020 electricity could be produced from power towers for 5.47 ₥/kWh and for 6.21 ₥/kWh from parabolic troughs. The capacity factor for power towers was estimated to be 72.9% and 56.2% for parabolic troughs. There is some hope that the development of cheap, durable, mass producible heliostat power plant components could bring this cost down. Dish designs A parabolic solar dish concentrating the sun's rays on the heating element of a Stirling engine. The entire unit acts as a solar tracker. A dish system uses a large, reflective, parabolic dish (similar in shape to satellite television dish). It focuses all the sunlight that strikes the dish up onto to a single point above the dish, where a receiver captures the heat and transforms it into a useful form. Typically the dish is coupled with a Stirling engine in a Dish-Stirling System, but also sometimes a steam engine is used. These create rotational kinetic energy that can be converted to electricity using an electric generator. The advantage of a dish system is that it can achieve much higher temperatures due to the higher concentration of light (as in tower designs). Higher temperatures leads to better conversion to electricity and the dish system is very efficient on this point. However, there are also some disadvantages. Heat to electricity conversion requires moving parts and that results in maintenance. In general, a centralized approach for this conversion is better than the dencentralized concept in the dish design. Second, the (heavy) engine is part of the moving structure, which requires a rigid frame and strong tracking system. Furthermore, parabolic mirrors are used instead of flat mirrors and tracking must be dual-axis. In 2005 Southern California Edison announced an agreement to purchase solar powered Stirling engines from Stirling Energy Systems over a twenty year period and in quantities (20,000 units) sufficient to generate 500 megawatts of electricity. [38] Stirling Energy Systems announced another agreement with San Diego Gas & Electric to provide between 300 and 900 megawatts of electricity. However, as of October 2007 it was unclear whether any progress had been made toward the construction of the 1 MW test plant, which was supposed to come online some time in 2007. Fresnel reflectors Wind load is avoided by the low position of the mirrors. Light construction of tracking system due to separation from the receiver.
A linear Fresnel reflector power plant uses a series of long, narrow, shallow-curvature (or even flat) mirrors to focus light onto one or more linear receivers positioned above the mirrors. On top of the receiver a small parabolic mirror can be attached for further focusing the light. These systems aim to offer lower overall costs by sharing a receiver between several mirrors (as compared with trough and dish concepts), while still using the simple line-focus geometry with one axis for tracking. This is similar to the trough design (and different from central towers and dishes with dual-axis). The receiver is stationary and so fluid couplings are not required (as in troughs and dishes). The mirrors also do not need to support the receiver, so they are structurally simpler. When suitable aiming strategies are used (mirrors aimed at different receivers at different times of day), this can allow a denser packing of mirrors on available land area. Recent prototypes of these types of systems have been built in Australia (CLFR) and by Solarmundo in Belgium. The Solarmundo research and development project, with its pilot plant at Liège, was closed down after successful proof of concept of the Linear Fresnel technology. Subsequently, Solar Power Group GmbH (SPG), based in Munich, Germany, was founded by some Solarmundo team members. A Fresnel-based prototype with direct steam generation was built by SPG in conjunction with the German Aerospace Center (DLR). Based on the Australian prototype, a 177MW plant had been proposed near San Luis Obispo in California and would be built by Ausra But Ausra sold its planned California solar farm to First Solar. First Solar will not build the Carrizo project, and the deal has resulted in the cancellation of Ausra’s contract to provide 177 megawatts to P.G.& E Small capacity plants are an enormous economical challenge with conventional parabolic trough and drive design - few companies build such small projects. There are plans for SHP Europe, former Ausra subsidiary, to build a 6.5 MW combined cycle plant in Portugal. The German company SK Energy) has plans to build several small 1-3 MW plants in Southern Europe (esp. in Spain) using Fresnel mirror and steam drive technology. In May 2008, the German Solar Power Group GmbH and the Spanish Laer S.L. agreed the joint execution of a solar thermal power plant in central Spain. This will be the first commercial solar thermal power plant in Spain based on the Fresnel collector technology of the Solar Power Group. The planned size of the power plant will be 10 MW a solar thermal collector field with a fossil co-firing unit as backup system. The start of constructions is planned for 2009. The project is located in Gotarrendura, a small renewable energy pioneering village, about 100 km northwest of Madrid, Spain. A Multi-Tower Solar Array (MTSA) concept, that uses a point-focus Fresnel reflector idea, has also been developed, but has not yet been prototyped. Since March 2009, the Fresnel solar power plant PE 1 of the German company Novatec Biosol is in commercial operation in southern Spain . The solar thermal power plant is based on linear Fresnel collector technology and has an electrical capacity of 1.4 MW. Beside a conventional power block, PE 1 comprises a solar boiler with mirror surface of around 18,000m². The steam is generated by concentrating direct solar irradiation onto a linear receiver which is 7.40m above the ground. An absorber tube is positioned in the focal line of the mirror field in which water is evaporated directly into saturated steam at 270°C and at a pressure of 55 bar by the concentrated solar energy. File:Fresnel solar power plant.jpg Fresnel solar power plant PE 1 in southern Spain Linear Fresnel Reflector (LFR) and compact-LFR Technologies Rival single axis tracking technologies include the relatively new Linear Fresnel reflector (LFR) and compact-LFR (CLFR) technologies. The LFR differs from that of the parabolic trough in that the absorber is fixed in space above the mirror field. Also, the reflector is composed of many low row
segments, which focus collectively on an elevated long tower receiver running parallel to the reflector rotational axis. This system offers a lower cost solution as the absorber row is shared among several rows of mirrors. However, one fundamental difficulty with the LFR technology is the avoidance of shading of incoming solar radiation and blocking of reflected solar radiation by adjacent reflectors. Blocking and shading can be reduced by using absorber towers elevated higher or by increasing the absorber size, which allows increased spacing between reflectors remote from the absorber. Both these solutions increase costs, as larger ground usage is required. The compact linear Fresnel reflector (CLFR) offers an alternate solution to the LFR problem. The classic LFR has only one linear absorber on a single linear tower. This prohibits any option of the direction of orientation of a given reflector. Since this technology would be introduced in a large field, one can assume that there will be many linear absorbers in the system. Therefore, if the linear absorbers are close enough, individual reflectors will have the option of directing reflected solar radiation to at least two absorbers. This additional factor gives potential for more densely packed arrays, since patterns of alternative reflector inclination can be set up such that closely packed reflectors can be positioned without shading and blocking. CLFR power plants offer reduced costs in all elements of the solar array. These reduced costs encourage the advancement of this technology. Features that enhance the cost effectiveness of this system compared to that of the parabolic trough technology include minimized structural costs, minimized parasitic pumping losses, and low maintenance. Minimized structural costs are attributed to the use of flat or elastically curved glass reflectors instead of costly sagged glass reflectors are mounted close to the ground. Also, the heat transfer loop is separated from the reflector field, avoiding the cost of flexible high pressure lines required in trough systems. Minimized parasitic pumping losses are due to the use of water for the heat transfer fluid with passive direct boiling. The use of glassevacuated tubes ensures low radiative losses and is inexpensive. Studies of existing CLFR plants have been shown to deliver tracked beam to electricity efficiency of 19% on an annual basis as a preheater. Fresnel lenses Prototypes of Fresnel lens concentrators have been produced for the collection of thermal energy by International Automated Systems. No full-scale thermal systems using Fresnel lenses are known to be in operation, although products incorporating Fresnel lenses in conjunction with photovoltaic cells are already available. The advantage of this design is that lenses are cheaper than mirrors. Furthermore, if a material is chosen that has some flexibility, then a less rigid frame is required to withstand wind load. MicroCSP "MicroCSP" references solar thermal technologies in which concentrating solar power (CSP) collectors are based on the designs used in traditional Concentrating Solar Power systems found in the Mojave Desert but are smaller in collector size, lighter and operate at lower thermal temperatures usually below 600 degrees F. These systems are designed for modular field or rooftop installation where they are easy to protect from high winds, snow and humid deployments. Solar manufacturer Sopogy completed construction on a 1MW CSP plant at the Natural Energy Laboratory of Hawaii. MicroCSP is used for community-sized power plants (1MW to 50MW), for industrial, agricultural and manufacturing 'process heat' applications, and when large amounts of hot water are needed, such as resort swimming pools, water parks, large laundry facilities, sterilization, distillation and other such uses.
Heat exchange Heat in a solar thermal system is guided by five basic principles: heat gain; heat transfer; heat storage; heat transport; and heat insulation. Here, heat is the measure of the amount of thermal energy an object contains and is determined by the temperature, mass and specific heat of the object. Heat gain is the heat accumulated from the sun in the system. Solar thermal heat is trapped using the greenhouse effect; the greenhouse effect in this case is the ability of a reflective surface to transmit short wave radiation and reflect long wave radiation. Heat and infrared radiation (IR) are produced when short wave radiation light hits the absorber plate, which is then trapped inside the collector. Fluid, usually water, in the absorber tubes collect the trapped heat and transfer it to a heat storage vault. Heat is transferred either by conduction or convection. When water is heated, kinetic energy is transferred by conduction to water molecules throughout the medium. These molecules spread their thermal energy by conduction and occupy more space than the cold slow moving molecules above them. The distribution of energy from the rising hot water to the sinking cold water contributes to the convection process. Heat is transferred from the absorber plates of the collector in the fluid by conduction. The collector fluid is circulated through the carrier pipes to the heat transfer vault. Inside the vault, heat is transferred throughout the medium through convection. Heat storage enables solar thermal plants to produce electricity during hours without sunlight. Heat is transferred to a thermal storage medium in an insulated reservoir during hours with sunlight, and is withdrawn for power generation during hours lacking sunlight. Thermal storage mediums will be discussed in a heat storage section. Rate of heat transfer is related to the conductive and convection medium as well as the temperature differences. Bodies with large temperature differences transfer heat faster than bodies with lower temperature differences. Heat transport refers to the activity in which heat from a solar collector is transported to the heat storage vault. Heat insulation is vital in both heat transport tubing as well as the storage vault. It prevents heat loss, which in turn relates to energy loss, or decrease in the efficiency of the system. Heat storage Heat storage allows a solar thermal plant to produce electricity at night and on overcast days. This allows the use of solar power for baseload generation as well as peak power generation, with the potential of displacing both coal and natural gas fired power plants. Additionally, the utilization of the generator is higher which reduces cost. Heat is transferred to a thermal storage medium in an insulated reservoir during the day, and withdrawn for power generation at night. Thermal storage media include pressurized steam, concrete, a variety of phase change materials, and molten salts such as sodium and potassium nitrate. Steam accumulator The PS10 solar power tower stores heat in tanks as pressurized steam at 50 bar and 285째C. The steam condenses and flashes back to steam, when pressure is lowered. Storage is for one hour. It is suggested that longer storage is possible, but that has not been proven yet in an existing power plant. Molten salt storage A variety of fluids have been tested to transport the sun's heat, including water, air, oil, and sodium, but molten salt was selected as best. Molten salt is used in solar power tower systems because it is liquid at atmosphere pressure, it provides an efficient, low-cost medium in which to store thermal energy, its operating temperatures are compatible with today's high-pressure and high-temperature steam turbines, and it is non-flammable and nontoxic. In addition, molten salt is used in the chemical
and metals industries as a heat-transport fluid, so experience with molten-salt systems exists in nonsolar settings. The molten salt is a mixture of 60 percent sodium nitrate and 40 percent potassium nitrate, commonly called saltpeter. The salt melts at 430 째F (220 째C) and is kept liquid at 550 째F (290 째C) in an insulated storage tank. The uniqueness of this solar system is in de-coupling the collection of solar energy from producing power, electricity can be generated in periods of inclement weather or even at night using the stored thermal energy in the hot salt tank. Normally tanks are well insulated and can store energy for up to a week. As an example of their size, tanks that provide enough thermal storage to power a 100-megawatt turbine for four hours would be about 30 feet tall and 80 feet in diameter. The Andasol power plant in Spain is the first commercial solar thermal power plant to utilize molten salt for heat storage and nighttime generation. It came online March 2009 Graphite heat storage Direct The proposed power plant in Cloncurry Australia will store heat in purified graphite. The plant has a power tower design. The graphite is located on top of the tower. Heat from the heliostats goes directly to the storage. Heat for energy production is drawn from the graphite. This simplifies the design. Indirect Molten salts coolants are used to transfer heat from the reflectors to heat storage vaults. The heat from the salts are transferred to a secondary heat transfer fluid via a heat exchanger and then to the storage media, or alternatively, the salts can be used to directly heat graphite. Graphite is used as it has relatively low costs and compatibility with liquid fluoride salts. The high mass and volumetric heat capacity of graphite provide an efficient storage medium. Phase-change materials for storage Phase Change Material (PCMs) offer an alternate solution in energy storage. Using a similar heat transfer infrastructure, PCMs have the potential of providing a more efficient means of storage. PCMs can be either organic or inorganic materials. Advantages of organic PCMs include no corrosives, low or no undercooling, and chemical and thermal stability. Disadvantages include low phase-change enthalpy, low thermal conductivity, and inflammability. Inorganics are advantageous with greater phase-change enthalpy, but exhibit disadvantages with undercooling, corrosion, phase separation, and lack of thermal stability. The greater phase-change enthalpy in inorganic PCMs make hydrates salts a strong candidate in the solar energy storage field. Use of water A design which requires water for condensation or cooling may conflict with location of solar thermal plants in desert areas with good solar radiation but limited water resources. The conflict is illustrated by plans of Solar Millennium, a German company, to build a plant in the Amargosa Valley of Nevada which would require 20% of the water available in the area. Some other projected plants by the same and other companies in the Mojave Desert of California may also be affected by difficulty in obtaining adequate and appropriate water rights. California water law currently prohibits use of potable water for cooling. Other designs require less water. The proposed Ivanpah Solar Power Facility in south-eastern California will conserve scarce desert water by using air-cooling to convert the steam back into water. Compared to conventional wet-cooling, this results in a 90 percent reduction in water usage . The water is then returned to the boiler in a closed process which is environmentally-friendly.
Conversion rates from solar energy to electrical energy Of all of these technologies the solar dish/stirling engine has the highest energy efficiency. A single solar dish-Stirling engine installed at Sandia National Laboratories National Solar Thermal Test Facility produces as much as 25 kW of electricity, with a conversion efficiency of 31.25%. Solar parabolic trough plants have been built with efficiencies of about 20%. Fresnel reflectors have an efficiency that is slightly lower (but this is compensated by the denser packing). The gross conversion efficiencies (taking into account that the solar dishes or troughs occupy only a fraction of the total area of the power plant) are determined by net generating capacity over the solar energy that falls on the total area of the solar plant. The 500-megawatt (MW) SCE/SES plant would extract about 2.75% of the radiation (1 kW/m²; see Solar power for a discussion) that falls on its 4,500 acres (18.2 km²). For the 50 MW AndaSol Power Plant that is being built in Spain (total area of 1,300×1,500 m = 1.95 km²) gross conversion efficiency comes out at 2.6% Furthermore, efficiency does not directly relate to cost: on calculating total cost, both efficiency and the cost of construction and maintenance should be taken into account. Levelised cost Since a solar power plant does not use any fuel, the cost consists mostly of capital cost with minor operational and maintenance cost. If the lifetime of the plant and the interest rate is known, then the cost per kWh can be calculated. This is called the levelised energy cost. The first step in the calculation is to determine the investment for the production of 1 kWh in a year. Example, the fact sheet of the Andasol 1 project shows a total investment of 310 million euros for a production of 179 GWh a year. Since 179 GWh is 179 million kWh, the investment per kWh a year production is 310 / 179 = 1.73 euro. Another example is Cloncurry solar power station in Australia. It is planned to produce 30 million kWh a year for an investment of 31 million Australian dollars. So, if this is achieved in reality, the cost would be 1.03 Australian dollar for the production of 1 kWh in a year. This would be significantly cheaper than Andasol 1, which can partially be explained by the higher radiation in Cloncurry over Spain. The investment per kwh cost for one year should not be confused with the cost per kwh over the complete lifetime of such a plant. In most cases the capacity is specified for a power plant (for instance Andasol 1 has a capacity of 50MW). This number is not suitable for comparison, because the capacity factor can differ. If a solar power plant has heat storage, then it can also produce output after sunset, but that will not change the capacity factor, it simply displaces the output. The average capacity factor for a solar power plant, which is a function of tracking, shading and location, is about 20%, meaning that a 50MW capacity power plant will typically provide a yearly output of 50 MW × 24 hrs × 365 days × 20% = 87,600 MWh/year, or 87.6 GWh/yr. Although the investment for one kWh year production is suitable for comparing the price of different solar power plants, it doesn't give the price per kWh yet. The way of financing has a great influence on the final price. If the technology is proven, an interest rate of 7% should be possible. However, for a new technology investors want a much higher rate to compensate for the higher risk. This has a significant negative effect on the price per kWh. Independent of the way of financing, there is always a linear relation between the investment per kWh production in a year and the price for 1 kWh (before adding operational and maintenance cost). In other words, if by enhancements of the technology the investments drop by 20%, then the price per kWh also drops by 20%. If a way of financing is assumed where the money is borrowed and repaid every year, in such way that the debt and interest decreases, then the following formula can be used to calculate the division factor: (1 - (1 + interest / 100) ^ -lifetime) / (interest / 100). For a lifetime of 25 years and an interest rate of 7%, the division factor is 11.65. For example, the investment of Andasol 1 was 1.73 euro per kWh, divided by 11.65 results in a price of 0.15 euro per kWh. If one cent operation and maintenance cost is added, then the levelized cost is 0.16 euro per kWh. Other ways of financing, different way of
debt repayment, different lifetime expectation, different interest rate, may lead to a significantly different number. If the cost per kWh may follow the inflation, then the inflation rate can be added to the interest rate. If an investor puts his money on the bank for 7%, then he is not compensated for inflation. However, if the cost per kWh is raised with inflation, then he is compensated and he can add 2% (a normal inflation rate) to his return. The Andasol 1 plant has a guaranteed feed-in tariff of 0.21 euro for 25 years. If this number is fixed, after 25 years with 2% inflation, 0.21 euro will have a value comparable with 0.13 euro now. Finally, there is some gap between the first investment and the first production of electricity. This increases the investment with the interest over the period that the plant is not active yet. The modular solar dish (but also solar photovoltaic and wind power) have the advantage that electricity production starts after first construction. Given the fact that solar thermal power is reliable, can deliver peak load and does not cause pollution, a price of US$0.10 per kWh starts to become competitive. Although a price of US$0.06 has been claimed With some operational cost a simple target is 1 dollar (or lower) investment for 1 kWh production in a year.
Solar Energy Development Environmental Considerations Benefits of Solar: SUMMARY Extends the Workday It is dark by 6:30 year round in the equatorial latitudes. Electric lighting allows families to extend their workday into the evening hours. Many villages where SELF has installed solar lights now boast home craft industries. Improves Health Fumes from kerosene lamps in poorly ventilated houses are a serious health problem in much of the world where electric light is unavailable. The World Bank estimates that 780 million women and children breathing kerosene fumes inhale the equivalent of smoke from 2 packs of cigarettes a day. Stems Urban Migration Improving the quality of life through electrification at the rural household and village level helps stem migration to mega-cities. Also, studies have shown a direct correlation between the availability of electric light and lower birth rates. Improves Fire-Reduction Kerosene lamps are a serious fire hazard in the developing world, killing and maiming tens of thousands of people each year. Kerosene, diesel fuel and gasoline stored for lamps and small generators are also a safety threat, whereas solar electric light is entirely safe. Improves Literacy Electric light improves literacy, because people can read after dark more easily than they can by candle or lamplight. Schoolwork improves and eyesight is safeguarded when children study by electric light. With the advent of television and radio, people previously cut off from electronic information, education, and entertainment can become part of the modern world without leaving home. Conserves Foreign Exchange
As much as 90% of the export earnings of some developing countries are used to pay for imported oil, most of it for power generation. Capital saved by not building additional large power plants can be used for investment in health, education, economic development, and industry. Expanding solar rural electrification creates jobs and business opportunities based on an appropriate technology in a decentralized marketplace. Conserves Energy Solar electricity for the Third World is clearly the most effective energy conservation program because it conserves costly conventional power for urban areas, town market centers, and industrial and commercial uses, leaving decentralized PV-generated power to provide the lighting and basic electrical needs of the majority of the developing world's rural populations. Reduces Maintenance Use of a SHS rather than gensets or kerosene lamps reduces the time and expense of refueling and maintenance. Kerosene lamps and diesel generators must be filled several times per day. In rural areas, purchasing and transporting of kerosene or diesel fuel is often both difficult and expensive. Diesel generators require periodic maintenance and have a short lifespan. Car batteries, used to power TVs must often be transported miles for recharging. SHS, however, require no fuel, and will last for 20 years with minimal servicing. Benefits of Solar: HEALTH Reduces kerosene-induced fires Kerosene lamps are a serious fire hazard in the developing world, killing and maiming tens of thousands of people each year. Kerosene, diesel fuel and gasoline stored for lamps and small generators are also a safety threat, whereas solar electric light is entirely safe. Improves indoor air quality Fumes from kerosene lamps in poorly ventilated houses are a serious health problem in much of the world where electric light is unavailable. The World Bank estimates that 780 million women and children breathing kerosene fumes inhale the equivalent of smoke from 2 packs of cigarettes a day. Increases effectiveness of health programs Use of a solar electric lighting systems by rural health centers increases the quality of health care provided. Solar electric systems improve patient diagnoses through brighter task lighting and use of electrically-lit microscopes. Photovoltaics can also power televisions and VCRs to educate health workers and patients about preventative care, medical procedures, and other health care provisions. Finally, solar electric refrigerators have a higher degree of temperature control than kerosene units, leading to lower vaccine spoilage rates, and increased immunization effectiveness. Allows telemedicine Telemedicine is the use of telecommunications technology to provide, enhance, or expedite health care services, by accessing off-site databases, linking clinics or physicians' offices to central hospitals, or transmitting x-rays or other diagnostic images for examination at another site. Deep in the Brazilian Amazon, SELF demonstrated the feasibility of telemedicine in remote areas by using a combination of solar power and satellite communications. Within moments of plugging in the new telemedicine device, local Caboclo Indians can have meaurements of blood pressure, body temperature, pulse, and blood-oxygen uploaded via satellite to the University of Southern Alabama for remote diagnosis. Benefits of Solar: ENVIRONMENT
Reduces local air pollution Use of solar electric systems decreases the amount of local air pollution. With a decrease in the amount of kerosene used for lighting, there is a corresponding reduction in the amount of local pollution produced. Solar rural electrification also decreases the amount of electricity needed from small diesel generators. Offsets greenhouse gases Photovoltaic systems produce electric power with no carbon dioxide (CO2) emissions. Carbon emission offset is calculated at approximately 6 tons of CO2 over the twenty-year life of one PV system. Conserves energy Solar electricity for the Third World is an effective energy conservation program because it conserves costly conventional power for urban areas, town market centers, and industrial and commercial uses, leaving decentralized PV-generated power to provide the lighting and basic electrical needs of the majority of the developing world's rural populations. Reduces need for dry-cell battery disposal Small dry-cell batteries for flashlights and radios are used throughout the unelectrified world. Most of these batteries are disposable lead-acid cells which are not recycled. Lead from disposed drycells leaches into the ground, contaminating the soil and water. Solar rural electrification dramatically decreases the need for disposable dry-cell batteries. Over 12 billion dry-cell batteries were sold in 1993. Benefits of Solar: EDUCATIONAL Improves literacy Solar rural electrification improves literacy by providing high quality electric reading lights. Electric lighting is far brighter than kerosene lighting or candles. Use of solar electric light aids students in studying during evening hours. Increases access to news and information Photovoltaics give rural areas access to news and educational programming through television and radio broadcasts. With the advent of television and radio, people previously cut off from electronic information, education, and entertainment can become part of the modern world without leaving home. Enables evening education classes Ongoing education classes and adult literacy classes can be held during the evening in solar-lit community centers. SELF has electrified community centers and schools in many countries, and has witnessed the development of adult literacy and professional classes possible with the introduction of solar electric lighting systems in community centers. Facilitates wireless rural telephony Solar electricity, when coupled with wireless communications, makes it possible to introduce rural telephony and data communication services to remote villages. Solar Home Systems ROLE
Rural households currently using kerosene lamps for lighting and disposable or automotive batteries for operating televisions, radios, and other small appliances are the principal market for the SHS. Solar PV is affordable to an increasing segment of the Third World's off-grid rural populations. For home lighting, the cost of an SHS is comparable to a family's average monthly expenditure for candles, kerosene or dry-cell batteries. Besides providing lighting, an SHS can also power a small TV. In addition, a family with an SHS need no longer purchase expensive drycell batteries to operate its radio-cassette player, which nearly every family has. Solar PV is competitive with its alternatives: kerosene, dry-cell batteries, candles, battery re-charging from the grid, Gensets, and grid extension. Approximately 400,000 families in the developing world are already using small, household solar PV systems to power fluorescent lights, radio-cassette players, 12 volt black-and-white TVs, and other small appliances. These families, living mostly in remote rural areas, already constitute the largest group of domestic users of solar electricity in the world. For them, there is no other affordable or immediately available source of electric power. These systems have been sold mostly by small entrepreneurs applying their working knowledge of this proven technology to serve rural families who need small amounts of power for electric lights, radios and TVs. The success of SHS implementation has been greatly determined by quality of the components and the availability of ongoing service and maintenance. When well-designed systems have received regular ongoing maintenance they have performed successfully over many years. However, when poorly designed components have been used, or when no after-sales service was available, systems often fail. Past failures of these systems has undermined local confidence. Fly-by-night salespeople have sold thousands of substandard SHS in South Africa, for example, which failed shortly after installation. Well-designed components and after-sales service and maintenance have become recognized as essential parts of a successful PV program. Many of these SHS were provided by non-governmental organizations (like SELF) or through government-sponsored programs with international donor support, such as in Zimbabwe where 10,000 SHS are being installed on a financed, full-cost-recovery basis (in a program designed by SELF for the United Nations in 1991.) In Bolivia, 2,500 SHS are being leased to users by a cooperative "utility." In Kenya, over 20,000 SHS have been installed since the mid-'80's by independent businessmen on a strictly cash basis. The World Bank estimates that 50,000 SHS have been installed in China, 40,000 in Mexico, and 20,000 in Indonesia. According to the United Nations Development Programme, 400 million families (nearly two billion people) have no access to electricity. The European Union's renewable energy organization EuroSolar estimates the global market for solar photovoltaic home lighting systems is 200 million families. Based on market studies in India, China, Sri Lanka, Zimbabwe, South Africa and Kenya conducted by various international development agencies over the past 5 years, the consensus is that approximately 5% of most rural populations can pay cash for an SHS, 20 to 30% can afford a SHS with short or medium term credit, and another 25% could afford an SHS with long term credit or leasing. Solar Home Systems ROLE Rural households currently using kerosene lamps for lighting and disposable or automotive batteries for operating televisions, radios, and other small appliances are the principal market for the SHS. Solar PV is affordable to an increasing segment of the Third World's off-grid rural populations. For home lighting, the cost of an SHS is comparable to a family's average monthly expenditure for candles, kerosene or dry-cell batteries. Besides providing lighting, an SHS can also power a small TV. In addition, a family with an SHS need no longer purchase expensive drycell batteries to operate its radio-cassette player, which nearly every family has. Solar PV is competitive with its alternatives: kerosene, dry-cell batteries, candles, battery re-charging from the grid, Gensets, and grid extension. Approximately 400,000 families in the developing world are already using small, household solar PV systems to power fluorescent lights, radio-cassette players, 12 volt black-and-white TVs, and
other small appliances. These families, living mostly in remote rural areas, already constitute the largest group of domestic users of solar electricity in the world. For them, there is no other affordable or immediately available source of electric power. These systems have been sold mostly by small entrepreneurs applying their working knowledge of this proven technology to serve rural families who need small amounts of power for electric lights, radios and TVs. The success of SHS implementation has been greatly determined by quality of the components and the availability of ongoing service and maintenance. When well-designed systems have received regular ongoing maintenance they have performed successfully over many years. However, when poorly designed components have been used, or when no after-sales service was available, systems often fail. Past failures of these systems has undermined local confidence. Fly-by-night salespeople have sold thousands of substandard SHS in South Africa, for example, which failed shortly after installation. Well-designed components and after-sales service and maintenance have become recognized as essential parts of a successful PV program. Many of these SHS were provided by non-governmental organizations (like SELF) or through government-sponsored programs with international donor support, such as in Zimbabwe where 10,000 SHS are being installed on a financed, full-cost-recovery basis (in a program designed by SELF for the United Nations in 1991.) In Bolivia, 2,500 SHS are being leased to users by a cooperative "utility." In Kenya, over 20,000 SHS have been installed since the mid-'80's by independent businessmen on a strictly cash basis. The World Bank estimates that 50,000 SHS have been installed in China, 40,000 in Mexico, and 20,000 in Indonesia. According to the United Nations Development Programme, 400 million families (nearly two billion people) have no access to electricity. The European Union's renewable energy organization EuroSolar estimates the global market for solar photovoltaic home lighting systems is 200 million families. Based on market studies in India, China, Sri Lanka, Zimbabwe, South Africa and Kenya conducted by various international development agencies over the past 5 years, the consensus is that approximately 5% of most rural populations can pay cash for an SHS, 20 to 30% can afford a SHS with short or medium term credit, and another 25% could afford an SHS with long term credit or leasing. Utility-scale solar energy environmental considerations include land disturbance/land use impacts, visual impacts, impacts associated with hazardous materials, and potential impacts on water and other resources, depending on the solar technology employed. Solar power plants reduce the environmental impacts of combustion used in fossil fuel power generation such as green house gas and other air pollution emissions. However, concerns have been raised over land disturbance, visual impacts, and the use of potentially hazardous materials in some systems. These and other concerns associated with solar energy development are discussed below, and will be addressed in the Solar Energy Development Programmatic EIS.
Land Disturbance/Land Use Impacts All utility-scale solar energy facilities require relatively large areas for solar radiation collection when used to generate electricity at a commercial scale, and the large arrays of solar collectors may interfere with natural sunlight, rainfall, and drainage, which could have a variety of effects on plants and animals. Solar arrays may also create avian perching opportunities that could affect both bird and prey populations. Land disturbance could also affect archeological resources. Solar facilities may interfere with existing land uses, such as grazing. Proper siting decisions can help to avoid land disturbance and land use impacts. Visual Impacts Because they are generally large facilities with numerous highly geometric and sometimes highly reflective surfaces, solar energy facilities may create visual impacts; however, being visible is not
necessarily the same as being intrusive. Aesthetic issues are by their nature highly subjective. Proper siting decisions can help to avoid aesthetic impacts to the landscape. Hazardous Materials Photovoltaic panels may contain hazardous materials, and although they are sealed under normal operating conditions, there is the potential for environmental contamination if they were damaged or improperly disposed upon decommissioning. Concentrating solar power systems may employ liquids such as oils or molten salts that may be hazardous, and present spill risks. In addition, various fluids are commonly used in most industrial facilities, such as hydraulic fluids, coolants, and lubricants. These fluids may in some cases be hazardous, and present a spill-related risk. Proper planning and good maintenance practices can be used to minimize impacts from hazardous materials. Impacts to Water Resources Parabolic trough and central tower systems typically use conventional steam plants to generate electricity, which commonly consume water for cooling. In arid settings, the increased water demand could strain available water resources. If the cooling water was contaminated through an accident, pollution of water resources could occur, although the risk would be minimized by good operating practices. Other Concerns Concentrating Solar Power (CSP) systems could potentially cause interference with aircraft operations if reflected light beams become misdirected into aircraft pathways. Operation of solar energy facilities, and especially concentrating solar power facilities involves high temperatures that may pose an environmental or safety risk. Like all electrical generating facilities, solar facilities produce electric and magnetic fields. Construction and decommissioning of utility-scale solar energy facilities would involve a variety of possible impacts normally encountered in construction/decommissioning of large-scale industrial facilities. If new electric transmission lines or related facilities were needed to service a new solar energy development, construction, operation, and decommissioning of the transmission facilities could also cause a variety of environmental impacts.
Economics of Solar Energy There are no telltale signs of a power plant -- no long lines of railroad cars filled with coal, no cooling towers releasing steam clouds, no smokestacks or big transformers. As the sun grows the corn, it also makes power on the roof of a metal building -- anywhere from 150 to 750 kilowatt hours per day, or enough to meet the needs of 15 typical houses. The Fayetteville Observer reported that the solar power plant at the Hamlin Cos.' shop near Benson, which makes duct work, is a sign of what may come. The 107,000-watt system is among the largest in the state but will soon be eclipsed by even bigger systems. Solar energy, proponents say, is on the cusp of a big wave. They are optimistic because: the solarenergy industry is no longer in its infancy. The technology, and those who install it, have made great strides with more efficient systems and more professional installers. Solar energy makes sense for environmental and economic reasons, experts say. A solar water heater system can cut residential utility bills by as much as 30 percent. North Carolina's legislators are pushing renewal energy. By 2021, utilities must get 12.5 percent of customers' power needs from renewal energy such as solar power or through energy efficiencies. The potential of solar power is affecting all segments of the market -- from energy giant Duke Power to small companies in Fayetteville. In June, Duke Power announced plans to install up to 850 solar panels throughout North Carolina at a cost of $100 million. Homes, schools, stores and factories will get solar panels. The idea is to produce power where it is used, rather than at large plants. Duke is also partnering with SunEdison on a solar farm in Davidson County. The proposed 16megawatt facility would be the largest photovoltaic solar facility in the country. SunEdison hopes to be operational by late 2010. All of the electricity generated would go to Duke. The solar panels would supply enough energy to meet the demands of 2,600 homes.
Progress Energy Carolina and SunPower Corp. are developing a 1-megawatt solar farm in Cary. Manufacturers are also taking advantage of the growing interest in solar power. The DuPont plant in northern Bladen County makes components used in about 40 percent of solar panels produced annually, said Steve Kalland of the North Carolina Solar Center. The center is part of N.C State University and is the state's clearinghouse for renewable energy programs and research. Sencera International Corp. announced recently it will invest $36.8 million to build a solar-module factory in Mecklenburg County. The state gave the company $62,000 from the One North Carolina Fund and $100,000 from the state's Green Business fund. Charlotte and Mecklenburg County will give Sencera about $1 million over three years -- equal to 90 percent of what the company will pay in property taxes during that time -- to satisfy the local match requirements of the Green Fund grant. It's not only the big boys who see opportunity. Hamlin has been in the roofing business for 54 years. When company officials started looking at solar energy, they soon realized it was more than an addon. "This is not a roofing accessory," said William Hamlin, the executive vice president of Hamlin Energy Solutions. "This is a power plant on someone's roof." In March, the company installed 24,000 square feet of photovoltaic strips on the roof of the Benson plant. The panels are connected so that if one panel goes out, the remaining panels continue to work. The panels have semi-conductors that turn sunlight into power. Peak production is between 11 a.m. and 3 p.m. Inverters convert the electricity to alternating current. The output immediately goes to a transformer owned by South River Electric Membership Corp. The solar panels provide about 30 percent of the shop's needs. Hamlin invested about $760,000 in its solar roof. A scaffolding allows people to climb up to see the thin, purple tiles. The company uses the roof for both training and demonstrations. Most of all, Hamlin said, they try to show potential customers that solar energy is "clean, simple and safe." Alternative Energy Concepts of Fayetteville is another company that spun into the business. When the owners of Intelect Inc. -- an electrical contractor in Fayetteville -- looked into solar, they also decided they needed their own separate company. They formed Alternative Energy Concepts. "We knew electrical work -- there was no mystery there," said Joseph Sheffield of Alternative Energy Concepts. But there was a learning curve in understanding solar, he said. The inquiries have been nonstop since the company opened several months ago. It can install solar, wind or hydroelectric systems. Some of the interest has been in installing solar hot water-heating systems. During the mid-1970s, such systems were popular but bulky and not always reliable. Today's technology still uses large panels that are 4 feet by 8 feet. But they are more efficient. Distilled water circulating through the panels heats up, then runs through a control panel. Water from a hot-water heater also flows through the control panel. The systems are separate, but the heat is transferred. That decreases the need for the water heater's electrical element. Fayetteville lawyer Graham Gurnee and his wife, Elizabeth, consulted the book "Solar Energy For Dummies" when they considered installing a system. They decided to install a system at their home. Elizabeth Gurnee said the foremost reason was environmental. The second was economic; with federal and state tax credits, their system will pay for itself in about four years. Tax credits can pay for as much as 65 percent of a solar-energy system. The credits are needed, said Kalland of the North Carolina Solar Center, to offset the high cost. But the costs are coming down, and Kalland predicts by 2020 the cost of producing solar power should be about the same as conventional electricity. Kalland does not expect solar to supplant conventional plants. He noted that today's largest solar plant produces about 20 megawatts of power. In comparison, the average conventional coal plant produces 800 megawatts daily. Provides superior lighting at least cost Solar home systems provide the least-cost means of receiving high quality home lighting. While providing brighter lighting, as well as access to radio and television. When low-cost financing is available, monthly payments for a solar home system are often below what a family is currently paying for kerosene, dry-cell batteries, candles, and recharging car batteries.
Extends the productive workday It is dark by 6:30 year round in the equatorial latitudes. Electric lighting allows families to extend their workday into the evening hours. Many villages where SELF has installed solar lights now boast home craft industries. In Vietnam, SELF installed solar outdoor lights in two village markets, allowing businesses to operate during the evening. Fosters micro-enterprise development Solar electricity helps promote local enterprises. Small shops and village markets can use the systems to provide lighting to operate during the evening. Small businesses utilizing electric sewing machines, water pumps, and computers are also benefited by the availability of solar electric systems Creates direct employment opportunities Local businesses selling and servicing solar home systems provide employment for local residents. Dealers, technicians, and local technicians all can be employed selling and servicing solar home systems. Facilitates development of micro-lending programs Revolving credit funds, and other financing mechanisms may be utilized for the purpose of purchasing solar home systems. Such credit funds serve as a vehicle for local financial institutions to begin loaning money to rural areas. Conserves foreign exchange As much as 90% of the export earnings of some developing countries are used to pay for imported oil, most of it for power generation. Capital saved by not building additional large power plants can be used for investment in health, education, economic development, and industry. Expanding solar rural electrification creates jobs and business opportunities based on an appropriate technology in a decentralized marketplace.
Chapter 6 Energy Sources and Impact on Environment Nonrenewable Energy Sources •
• • •
Oil and Petroleum Products o Gasoline o Diesel Fuel o Propane Natural Gas Coal Nuclear
Renewable Energy Sources • • • • • • •
Hydropower Biomass Ethanol Biodiesel Wind Geothermal Solar
•
Oil and Petroleum Products
How Does Oil Impact the Environment? Products from oil (petroleum products) help us do many things. We use them to fuel our irplanes, cars, and trucks, to heat our homes, and to make products like medicines and plastics. Even though petroleum products make life easier — finding, producing, moving, and using them can harm the environment through air and water pollution.
Emissions and Byproducts Are Produced from Burning Petroleum Products Petroleum products give off the following emissions when they are burned as fuel: • • • • • •
Carbon dioxide (CO2) Carbon monoxide (CO) Sulfur dioxide (SO2) Nitrogen oxides (NOX) and Volatile Organic Compounds (VOC) Particulate matter (PM) Lead and various air toxics such as benzene, formaldehyde, acetaldehyde, and 1,3-butadiene may be emitted when some types of petroleum are burned
Nearly all of these byproducts have negative impacts on the environment and human health: • • • • •
Carbon dioxide is a greenhouse gas and a source of global warming.1 SO2 causes acid rain, which is harmful to plants and to animals that live in water, and it worsens or causes respiratory illnesses and heart diseases, particularly in children and the elderly. NOX and VOCs contribute to ground-level ozone, which irritates and damages the lungs. PM results in hazy conditions in cites and scenic areas, and, along with ozone, contributes to asthma and chronic bronchitis, especially in children and the elderly. Very small, or “fine PM” is also thought to cause emphysema and lung cancer. Lead can have severe health impacts, especially for children, and air toxics are known or probable carcinogens
Laws Help Reduce Pollution from Oil Over the years, new technologies and laws have helped to reduce problems related to petroleum products. As with any industry, the Government monitors how oil is produced, refined, stored, and sent to market to reduce the impact on the environment. Since 1990, fuels like gasoline and diesel fuel have also been improved so that they produce less pollution when we use them.
Reformulated Fuels Because a lot of air pollution comes from cars and trucks, many environmental laws have been aimed at changing the make-up of gasoline and diesel fuel so that they produce fewer emissions. These "reformulated fuels" are much cleaner-burning than gasoline and diesel fuel were in 1990.
Technology Helps Reduce Drilling's "Footprint" Exploring and drilling for oil may disturb land and ocean habitats. New technologies have greatly reduced the number and size of areas disturbed by drilling, sometimes called "footprints."2 Satellites, global positioning systems, remote sensing devices, and 3-D and 4-D seismic technologies make it possible to discover oil reserves while drilling fewer wells.
The use of horizontal and directional drilling makes it possible for a single well to produce oil from a much bigger area. Today's production footprints are also smaller those 30 years ago because of the development of movable drilling rigs and smaller "slimhole" drilling rigs. When the oil in a well becomes uneconomic to produce, the well must be plugged below ground, making it hard to tell that it was ever there. As part of the "rigs-to-reefs" program, some old offshore rigs are tipped over and left on the sea floor to become artificial reefs that attract fish and other marine life. Within six months to a year after a rig is toppled, it becomes covered with barnacles, coral, sponges, clams, and other sea creatures. If oil is spilled into rivers or oceans, it can harm wildlife. When we talk about "oil spills," people usually think about oil that leaks from a ship that is involved in an accident. The amount of oil spilled from ships dropped significantly during the 1990s partly because new ships were required to have a "double-hull" lining to protect against spills.
The Greatest Share of Oil in the Sea Comes from Natural Seeps While oil spills from ships are the most well-known source of oil in ocean water, more oil actually gets into water from natural oil seeps coming from the ocean floor. Leaks also happen when we use petroleum products on land. For example, gasoline sometimes drips onto the ground when people are filling their gas tanks, when motor oil gets thrown away after an oil change, or when fuel escapes from a leaky storage tank. When it rains, the spilled products get washed into the gutter and eventually flow to rivers and into the ocean. Another way that oil sometimes gets into water is when fuel is leaked from motorboats and jet skis.
No Dumping/Drains to River Sign When a leak in a storage tank or pipeline occurs, petroleum products can also get into the ground, and the ground must be cleaned up. To prevent leaks from underground storage tanks, all buried tanks are supposed to be replaced by tanks with a double lining.
Gasoline Use Contributes to Air and Water Pollution Burning gasoline produces carbon dioxide, a major greenhouse gas. Scientists know with virtual certainty that increasing greenhouse gas concentrations tend to warm the planet.1 Gasoline is a highly flammable and toxic liquid. The vapors given off when it evaporates and the substances produced when it is burned (carbon monoxide, nitrogen oxides, particulate matter, and unburned hydrocarbons) contribute to air pollution. Burning a gallon of gasoline produces about 19 pounds of carbon dioxide.
Laws Such as the Clean Air Act Reduce Environmental Impact Americans use about 380 million gallons of gasoline every day. Reducing pollution from gasoline has been a focus of environmental laws in the United States. The Clean Air Act is the major law aimed at reducing air pollution. The Clean Air Act (first passed in 1970) and its amendments have aimed to reduce pollution from driving by requiring both cleaner cars and cleaner fuels (gasoline and diesel). The Environmental Protection Agency (EPA) put these goals into action by requiring the following: Removal of leaded gasoline — Leaded gasoline was officially banned in 1996 as a result of the Clean Air Act. Lead from gasoline proved to be a public health concern. The move away from leaded gasoline originally began in 1976 when catalytic converters were installed in new vehicles to reduce the emission of toxic air pollutants. Vehicles equipped with a catalytic converter cannot operate on leaded gasoline; the presence of lead in the fuel damages the catalytic converter. • •
•
Reformulated gasoline — The Clean Air Act Amendments of 1990 required the sale of a cleaner reformulated gasoline beginning in 1995 to reduce air pollution in certain metropolitan areas with the worst ground-level ozone pollution. Low sulfur gasoline — Beginning in 2006, refiners are now required to supply gasoline containing much less sulfur levels than in the past, reducing the sulfur levels in gasoline by 90%. Cutting the sulfur in gasoline reduces emissions from both old and new vehicles alike. In addition, the Clean Air Act requires all new cars to have new pollution control devices, which cannot work properly with higher sulfur fuels. Reduced risk of gasoline leaks — Gasoline leaks happen at gas stations every day. As we fill up our gas tanks, gasoline drips from the nozzle onto the ground and vapors leak from the open gas tank into the air. Gasoline leaks can also happen where we can’t see them in pipelines or underground storage tanks. Beginning in 1990, all buried tanks are supposed to be replaced by tanks with a double lining as an additional safeguard for preventing leaks.
In some places where gasoline leaked from storage tanks, one of the gasoline ingredients called methyl tertiary butyl ether (MTBE) made its way into local water supplies. Since MTBE made water taste bad and many people were worried about drinking it, a number of States banned the use of MTBE in gasoline, and the refining industry voluntarily moved away from using it when blending reformulated gasoline.
When diesel fuel is used, carbon dioxide is a byproduct. Carbon dioxide is a greenhouse gas that is linked to global climate change.1 Diesel-powered cars achieve 20-40% better fuel economy than gasoline-powered cars, especially in sport utility vehicles (SUVs) and light trucks, which now make up more than half of all new vehicle sales in the United States. Safety is another advantage of diesel fuel; it is less flammable than gasoline and other alternatives
Diesel Emissions The major disadvantage of diesel fuel is its harmful emissions. Significant progress has been made in reducing emissions from diesel engines. With new clean diesel technologies, today's trucks and buses are eight times cleaner than those built just a dozen years ago. In the future, diesel engines must become even cleaner in order to meet tightening environmental standards. New diesel fuels — some of which have lower sulfur content — can also help diesel vehicles achieve lower emissions. Ultra-low sulfur diesel (ULSD) fuel is highly refined for clean, complete combustion, and low emissions. ULSD is necessary for new engine technologies to work properly, and will eventually replace regular diesel fuel. Using low sulfur diesel fuel and adding exhaust control systems can reduce particulate emissions by up to 90% and nitrogen compounds (NOx) by 25-50%.
Even with these advances, diesel still contributes significantly to air pollution in the United States. It will take a long time for the new cleaner-burning diesel vehicles to replace older ones.
Propane Is a Clean-Burning Fossil Fuel Propane is a nonrenewable fossil fuel, like the natural gas and oil it is produced from. Like natural gas (methane), propane is colorless and odorless. Although propane is nontoxic and odorless, foulsmelling mercaptan is added to it to make gas leaks easy to detect. Propane is a clean burning fossil fuel, which is why it is often chosen to fuel indoor equipment such as fork lifts. Its clean burning properties and its portability also make it popular as an alternative transportation fuel.
Indoor Forklift Propane-fueled engines produce much fewer emissions of carbon monoxide and hydrocarbons compared to gasoline engines. Like all fossil fuels, propane emits water vapor and carbon dioxide, a greenhouse gas.
Natural Gas Use Contributes to Air Pollution Natural gas burns more cleanly than other fossil fuels. It has fewer emissions of sulfur, carbon, and nitrogen than coal or oil, and when it is burned, it leaves almost no ash particles. Being a cleaner fuel is one reason that the use of natural gas, especially for electricity generation, has grown so much. However, as with other fossil fuels, burning natural gas produces carbon dioxide which is a greenhouse gas. Greenhouse gases contribute to the "greenhouse effect."1 As with other fuels, natural gas also affects the environment when it is produced, stored, and transported. Because natural gas is made up mostly of methane (another greenhouse gas), small amounts of methane can sometimes leak into the atmosphere from wells, storage tanks, and pipelines. The natural gas industry is working to prevent any methane from escaping.
Technology Helps Reduce Drilling's "Footprint" Exploring and drilling for natural gas will always have some impact on land and marine habitats. But new technologies have greatly reduced the number and size of areas disturbed by drilling, sometimes called "footprints." Plus, the use of horizontal and directional drilling make it possible for a single well to produce gas from much bigger areas than in the past. Natural gas pipelines and storage facilities have a good safety record. This is important because when natural gas leaks it can cause explosions. Since raw natural gas has no odor, natural gas companies add a smelly substance to it so that people will know if there is a leak. If you have a
natural gas stove, you may have smelled this "rotten egg" smell of natural gas when the pilot light has gone out
Natural gas Pipelines
Coal and the Environment Environmental laws and modern technologies have greatly reduced the impact on the environment from the production and consumption of coal.
What Are Some Environmental Concerns In Coal Mining? Without proper care, mining can have a negative impact on ecosystems and water quality and alter landscapes and scenic views. Debris that chokes mountain streams can result from surface mining like mountaintop removal, and acidic water can drain from abandoned underground mines. Today restoring the land damaged by surface mining is an important part of the mining process. Because mining activities often come into contact with water resources, coal producers must also go to great efforts to prevent damage to ground and surface waters.
What Emissions and Byproducts Are Produced from Burning Coal? The combustion of coal produces several types of emissions that adversely affect the environment. The five principal emissions associated with coal consumption in the energy sector are: • • • • •
Sulfur dioxide (SO2), which has been linked to acid rain and increased incidence of respiratory illnesses Nitrogen oxides (NOx), which have been linked to the formation of acid rain and photochemical smog Particulates, which have been linked to the formation of acid rain and increased incidence of respiratory illnesses Carbon dioxide (CO2), which is the primary greenhouse gas emission from energy use. Mercury, which has been linked with both neurological and developmental damage in humans and other animals. Mercury concentrations in the air usually are low and of little direct concern. However, when mercury enters water — either directly or through deposition from the air — biological processes transform it into methylmercury, a highly toxic chemical that accumulates in fish and the animals (including humans) that eat fish.
How Are the Environmental Effects of Coal Use Diminished? Reducing the Impacts of Coal Use The Clean Air Act and the Clean Water Act require industries to reduce pollutants released into the air and the water. Industry has found several ways to reduce sulfur, nitrogen oxides (NOx), and other impurities from coal. They have found more effective ways of cleaning coal after it is mined, and coal consumers have shifted towards greater use of low sulfur coal. Power plants use flue gas desulfurization equipment, also known as "scrubbers," to clean sulfur from the smoke before it leaves their smokestacks. In addition, industry and government have cooperated to develop technologies that can remove impurities from coal or that make coal more energy-efficient so less needs to be burned. Equipment intended mainly to reduce SO2 (such as scrubbers), NOx (such as catalytic converters), and particulate matter (such as electrostatic precipitators and baghouses) is also able to reduce mercury emissions from some types of coal. Scientists are also working on new ways to reduce mercury emissions from coal-burning power plants. Research is underway to address emissions of carbon dioxide from coal combustion. Carbon capture separates CO2 from emissions sources and recovers it in a concentrated stream. The CO2 can then be sequestered, which puts CO2 into storage, possibly underground, in such a way that it will remain there permanently. Reuse and recycling can also diminish coal’s environmental impact. Land that was previously used for coal mining can be reclaimed for uses like airports, landfills, and golf courses. Waste products can also be captured by scrubbers to produce synthetic gypsum for wallboard. Major Components of a Coal-fired Power Plant with Carbon Capture
Nuclear Energy Is Energy from Atoms Nuclear energy is energy in the nucleus (core) of an atom. Atoms are tiny particles that make up every object in the universe. There is enormous energy in the bonds that hold atoms together.
Nuclear energy can be used to make electricity. But first the energy must be released. It can be released from atoms in two ways: nuclear fusion and nuclear fission. In nuclear fission, atoms are split apart to form smaller atoms, releasing energy. Nuclear power plants use this energy to produce electricity. In nuclear fusion, energy is released when atoms are combined or fused together to form a larger atom. This is how the sun produces energy. Fusion is the subject of ongoing research, but it is not yet clear that it will ever be a commercially viable technology for electricity generation.
Nuclear Fuel — Uranium The fuel most widely used by nuclear plants for nuclear fission is uranium. Uranium is nonrenewable, though it is a common metal found in rocks all over the world. Nuclear plants use a certain kind of uranium, referred to as U-235. This kind of uranium is used as fuel because its atoms are easily split apart. Though uranium is quite common, about 100 times more common than silver, U-235 is relatively rare. Most U.S. uranium is mined in the Western United States. Once uranium is mined, the U-235 must be extracted and processed before it can be used as a fuel. During nuclear fission, a small particle called a neutron hits the uranium atom and splits it, releasing a great amount of energy as heat and radiation. More neutrons are also released. These neutrons go on to bombard other uranium atoms, and the process repeats itself over and over again. This is called a chain reaction.
The sun is basically a giant ball of hydrogen gas undergoing fusion into helium gas and giving off vast amounts of energy in the proces
How Fission Uranium Atom
Splits
Nuclear Power Plants Produce No Carbon Dioxide The first sentence is questionable: is nuclear energy really "clean"? Unlike fossil fuel-fired power plants, nuclear reactors do not produce air pollution or carbon dioxide while operating. However, the processes for mining and refining uranium ore and making reactor fuel require large amounts of energy. Nuclear power plants have large amounts of metal and concrete, which also require large amounts of energy to manufacture. If fossil fuels are used to make the electricity and manufacture the power plant materials, then the emissions from burning those fuels could be associated with the electricity that nuclear power plants generate.
the
Nuclear Energy Produces Radioactive Waste The main environmental concerns for nuclear power are radioactive wastes such as uranium mill tailings, spent (used) reactor fuel, and other radioactive wastes. These materials can remain radioactive and dangerous to human health for thousands of years. They are subject to special regulations that govern their handling, transportation, storage, and disposal to protect human health and the environment. The U.S. Nuclear Regulatory Commission regulates the operation of nuclear power plants. Radioactive wastes are classified as low-level and high-level. The radioactivity in these wastes can range from just above natural background levels, as in mill tailings, to much higher levels, such as in spent reactor fuel or the parts inside a nuclear reactor. The radioactivity of nuclear waste decreases with the passage of time through a process called radioactive decay. The amount of time necessary to decrease the radioactivity of radioactive material to one-half the original level is called the radioactive half-life of the material. Radioactive waste with a short half-life is often stored temporarily before disposal in order to reduce potential radiation doses to workers who handle and transport the waste, as well as to reduce the radiation levels at disposal sites. By volume, most of the waste related to the nuclear power industry has a relatively low-level of radioactivity. Uranium mill tailings contain the radioactive element radium, which decays to produce radon, a radioactive gas. Most uranium mill tailings are placed near the processing facility or mill where they come from, and are covered with a barrier of a material such as clay to prevent radon from escaping into the atmosphere and then a layer of soil, rocks, or other materials to prevent erosion of the sealing barrier. The other types of low level radioactive waste are the tools, protective clothing, wiping cloths, and other disposable items that get contaminated with small amounts of radioactive dust or particles at nuclear fuel processing facilities and power plants. These materials are subject to special regulation that govern their handling, storage, and disposal so they will not come in contact with the outside environment. High-level radioactive waste consists of “irradiated� or used nuclear reactor fuel (i.e., fuel that has been used in a reactor to produce electricity). The used reactor fuel is in a solid form consisting of small fuel pellets in long metal tubes.
Spent Reactor Fuel Storage and Power Plant Decommissioning Spent reactor fuel assemblies are highly radioactive and must initially be stored in specially designed pools resembling large swimming pools, where water cools the fuel and acts as a radiation shield, or in specially designed dry storage containers. An increasing number of reactor operators now store their older spent fuel in dry storage facilities using special outdoor concrete or steel containers with air cooling. There is currently no permanent disposal facility in the United States for high-level nuclear waste. High-level waste is being stored at nuclear plants. When a nuclear power plant stops operating, the facility must be decommissioned. This involves safely removing the plant from service and reducing radioactivity to a level that permits other uses of the property. The Nuclear Regulatory Commission has strict rules governing nuclear power plant decommissioning that involve cleanup of radioactively contaminated plant systems and structures, and removal of the radioactive fuel.
Dry Storage Cask :Some canisters are designed to be placed vertically in robust above-ground concrete or steel structures
Nuclear Reactors and Power Plants Have Complex Safety and Security Features An uncontrolled nuclear reaction in a nuclear reactor can potentially result in widespread contamination of air and water with radioactivity for hundreds of miles around a reactor. The risk of this happening at nuclear power plants in the United States is considered to be very small due to the diverse and redundant barriers and numerous safety systems at nuclear power plants, the training and skills of the reactor operators, testing and maintenance activities, and the regulatory requirements and oversight of the Nuclear Regulatory Commission. A large area surrounding nuclear power plants is restricted and guarded by armed security teams. U.S. reactors have containment vessels that are designed to withstand extreme weather events and earthquakes.
Renewable Energy Hydropower Generators Produce Clean Electricity, but Hydropower Does Have Environmental Impacts Most dams in the United States were built mainly for flood control and supply of water for cities and irrigation. A small number of dams were built specifically for hydropower generation. While hydropower (hydro-electric) generators do not directly produce emissions of air pollutants, hydropower dams, reservoirs, and the operation of generators can have environmental impacts A dam to create a reservoir (or to divert water to a run-of-river hydropower plant) may obstruct migration of fish to their upstream spawning areas. A reservoir and operation of the dam can also change the natural water temperatures, chemistry, flow characteristics, and silt loads, all of which can lead to significant changes in the ecology (living organisms and the environment) and physical characteristics (rocks and land forms) of the river upstream and downstream. These changes may have negative impacts on native plants and animals in and next to the river, and in the deltas that form where rivers empty into the ocean. Reservoirs may cover important natural areas, agricultural land, and archeological sites, and cause the relocation of people. The physical impacts of a dam and reservoir, the operation of the dam, and use of the water can change the environment over a much wider area than that covered by a reservoir. While no new hydropower dams have recently been built in the United States, they are being built in other countries such as China. Manufacturing the concrete and steel used to construct these dams requires energy that may create emissions when produced. If fossil fuels are used as the energy sources to make these materials, then the emissions from burning those fuels could be associated with the electricity that hydropower facilities generate. However, given the long operating lifetime of a hydropower plant (50-100 years), these emissions are more than offset by the emissions that would have been produced if the electricity were generated by fossil fuel-fired power plants. Greenhouse gases, carbon dioxide and methane, may also form in reservoirs and be emitted to the atmosphere. The exact amount of greenhouse gases produced from hydropower plant reservoirs is uncertain. The emissions from reservoirs in tropical and temperate regions, including the United States, may be equal to or greater than the greenhouse effect of the carbon dioxide emissions from an equivalent amount of electricity generated with fossil fuels. Scientists at Brazil’s National Institute for Space Research designed a system to capture methane in a reservoir and burn it to produce electricity.
Fish Ladders Help Salmon Reach Their Spawning Grounds Hydro turbines kill and injure some of the fish that pass through the turbine. The U.S. Department of Energy has sponsored research and development of turbines that could reduce fish deaths to less than 2%, in comparison to fish kills of 5 to 10% for the best existing turbines.
Each Form of Biomass Has a Different Impact Biomass pollutes the air when it is burned, but not as much as fossil fuels do. Burning biomass fuels does not produce pollutants such as sulfur that can cause acid rain. When burned, biomass releases carbon dioxide, a greenhouse gas. But when biomass crops are grown, a nearly equivalent amount of carbon dioxide is captured through photosynthesis. Each of the different forms and uses of biomass impact the environment in a different way.
Burning Wood Because the smoke from burning wood contains pollutants like carbon monoxide and particulate matter, some areas of the country won't allow the use of wood-burning fireplaces or stoves on high pollution days. A special clean-burning technology can be added to wood-burning fireplaces and stoves so that they can be used even on days with the worst pollution.
Burning Municipal Solid Waste (MSW) or Wood Waste Burning municipal solid waste (MSW, or garbage) and wood waste to produce energy means that less of it has to get buried in landfills. Like coal plants, waste-to-energy plants produce air pollution when the fuel is burned to produce steam or electricity. Burning garbage releases the chemicals and substances found in the waste. Some of these chemicals can be dangerous to people, the environment, or both, if they are not properly controlled. Plants that burn waste to make electricity must use technology to prevent harmful gases and particles from coming out of their smoke stacks. The particles that are filtered out are added to the ash that is removed from the bottom of the furnace. Because the ash may contain harmful chemicals and metals, it must be disposed of carefully.
Controlling Air Emissions The Environmental Protection Agency (EPA) applies strict environmental rules to waste-to-energy plants. The EPA requires waste-to-energy plants to use anti-pollution devices, including scrubbers, fabric filters, and electrostatic precipitators. The EPA wants to ensure that harmful gases and particles don't go out the smokestack into the air. Scrubbers clean chemical gas emissions by spraying a liquid into the gas stream to neutralize the acids. Fabric filters and electrostatic precipitators remove particles from the emissions. The particles are then mixed with the ash that is removed from the bottom of the waste-to-energy plant's furnace when it is cleaned. A waste-to-energy furnace burns at such high temperatures (1,800 to 2,000째F) that many complex chemicals naturally break down into simpler, less harmful compounds. This chemical change is a kind of built-in anti-pollution device.
Disposing of Ash Another challenge is the disposal of the ash after combustion. Ash can contain high concentrations of various metals that were present in the original waste. Textile dyes, printing inks, and ceramics, for example, contain the metals lead and cadmium. Separating waste before combustion can solve part of the problem. Because batteries are the largest source of lead and cadmium in the solid waste stream, they should be taken out of the mix and not burned.
The EPA tests ash from waste-to-energy plants to make sure it's not hazardous. The test looks for chemicals and metals that would contaminate ground water by trickling through a landfill. Ash that is safe can be reused for many applications. About one-third of all the ash produced is used in landfills as a daily or final cover layer, to build roads, to make cement blocks, and even to make artificial reefs for marine animals.
Collecting Landfill Gas or Biogas Biogas is a gas composed mainly of methane and carbon dioxide that forms as a result of biological processes in sewage treatment plants, waste landfills, and livestock manure management systems. Methane is one of the greenhouse gases associated with global climate change.1 Many of these facilities capture and burn the biogas for heat or electricity generation. Burning methane is actually beneficial because methane is a stronger greenhouse gas than carbon dioxide. The electricity generated from biogas is considered "green power" in many states and may be used to meet state renewable portfolio standards (RPS).
Ethanol Ethanol was one of the first fuels used in automobiles, and now nearly all gasoline sold in the United States contains some ethanol. The Federal government has set a renewable fuel standard (RFS) that mandates increasing biofuels use through 2022, most of which will probably be ethanol. Ethanol and gasoline fuel mixtures burn cleaner and have higher octane than pure gasoline, but have higher "evaporative emissions" from fuel tanks and dispensing equipment. These evaporative emissions contribute to the formation of harmful, ground-level ozone and smog. Gasoline requires extra processing to reduce evaporative emissions before it is blended with ethanol. Carbon dioxide, a greenhouse gas, forms when ethanol burns, but growing plants like corn or sugarcane to make ethanol may offset these carbon dioxide emissions because plants absorb carbon dioxide as they grow.
Biodiesel Biodiesel was the fuel used in the first diesel engines. Compared to petroleum diesel, biodiesel combustion produces less sulfur oxides, particulate matter, carbon monoxide, and unburned and other hydrocarbons, but more nitrogen oxide. Similar to ethanol, biodiesel use may result in lower netcarbon dioxide emissions if the source of biodiesel are oils made from plants, which absorb carbon dioxide.
Biodiesel Burns Significantly Cleaner than Diesel Biodiesel is renewable, nontoxic, and biodegradable. Compared to diesel, biodiesel burns significantly cleaner. It produces fewer air pollutants like particulates, carbon monoxide, hydrocarbons, and air toxics. However, it does slightly increase emissions of nitrogen oxides
A Fuel That Smells Like French Fries Biodiesel produces less black smoke than regular diesel, and it smells better, too. Sometimes biodiesel exhaust smells like french fries!
A Fuel With No Sulfur Regular diesel fuel contains sulfur. Sulfur can cause damage to the environment when it is burned in fuels. The amount of sulfur in diesel fuel is regulated by the Federal government.
When sulfur is removed from regular diesel fuel, the fuel doesn't work as well. Adding a small amount of biodiesel can fix the problem. Biodiesel has no sulfur, so it can reduce sulfur levels in the Nation's diesel fuel supply while making engines run smoother.
Wind: A Clean Fuel In the 1970s, oil shortages pushed the development of alternative energy sources. In the 1990s, the push came from a renewed concern for the environment in response to scientific studies indicating potential changes to the global climate if the use of fossil fuels continues to increase. Wind energy is an economical power resource in many areas of the country. Wind is a clean fuel; wind power plants (also called wind farms) produce no air or water pollution because no fuel is burned to generate electricity. Growing concern about emissions from fossil fuel generation, increased government support, and higher costs for fossil fuels (especially natural gas and coal) have helped wind power capacity in the United States grow substantially over the past 10 years.
Drawbacks of Wind Machines The most serious environmental drawbacks to wind machines may be their negative effect on wild bird populations and the visual impact on the landscape. To some, the glistening blades of windmills on the horizon are an eyesore; to others, they're a beautiful alternative to conventional power plants.
Wind Power Solar Power Using solar energy produces no air or water pollution and no greenhouse gases, but does have some indirect impacts on the environment. For example, there are some toxic materials and chemicals, and various solvents and alcohols that are used in the manufacturing process of photovoltaic cells (PV), which convert sunlight into electricity. Small amounts of these waste materials are produced. In addition, large solar thermal power plants can harm desert ecosystems if not properly managed. Birds and insects can be killed if they fly into a concentrated beam of sunlight, such as that created by a "solar power tower." Some solar thermal systems use potentially hazardous fluids (to transfer heat) that require proper handling and disposal. Concentrating solar systems may require water for regular cleaning of the concentrators and receivers and for cooling the turbine-generator. Using water from underground wells may affect the ecosystem in some arid locations.
Array of Solar panels Solar Energy Development Environmental Considerations Utility-scale solar energy environmental considerations include land disturbance/land use impacts, visual impacts, impacts associated with hazardous materials, and potential impacts on water and other resources, depending on the solar technology employed. Solar power plants reduce the environmental impacts of combustion used in fossil fuel power generation such as green house gas and other air pollution emissions. However, concerns have been raised over land disturbance, visual impacts, and the use of potentially hazardous materials in some
systems. These and other concerns associated with solar energy development are discussed below, and will be addressed in the Solar Energy Development Programmatic EIS.
Land Disturbance/Land Use Impacts All utility-scale solar energy facilities require relatively large areas for solar radiation collection when used to generate electricity at a commercial scale, and the large arrays of solar collectors may interfere with natural sunlight, rainfall, and drainage, which could have a variety of effects on plants and animals. Solar arrays may also create avian perching opportunities that could affect both bird and prey populations. Land disturbance could also affect archeological resources. Solar facilities may interfere with existing land uses, such as grazing. Proper siting decisions can help to avoid land disturbance and land use impacts.
Visual Impacts Because they are generally large facilities with numerous highly geometric and sometimes highly reflective surfaces, solar energy facilities may create visual impacts; however, being visible is not necessarily the same as being intrusive. Aesthetic issues are by their nature highly subjective. Proper siting decisions can help to avoid aesthetic impacts to the landscape.
Hazardous Materials Photovoltaic panels may contain hazardous materials, and although they are sealed under normal operating conditions, there is the potential for environmental contamination if they were damaged or improperly disposed upon decommissioning. Concentrating solar power systems may employ liquids such as oils or molten salts that may be hazardous, and present spill risks. In addition, various fluids are commonly used in most industrial facilities, such as hydraulic fluids, coolants, and lubricants. These fluids may in some cases be hazardous, and present a spill-related risk. Proper planning and good maintenance practices can be used to minimize impacts from hazardous materials.
Impacts to Water Resources Parabolic trough and central tower systems typically use conventional steam plants to generate electricity, which commonly consume water for cooling. In arid settings, the increased water demand could strain available water resources. If the cooling water was contaminated through an accident, pollution of water resources could occur, although the risk would be minimized by good operating practices.
Other Concerns Concentrating Solar Power (CSP) systems could potentially cause interference with aircraft operations if reflected light beams become misdirected into aircraft pathways. Operation of solar energy facilities, and especially concentrating solar power facilities involves high temperatures that may pose an environmental or safety risk. Like all electrical generating facilities, solar facilities produce electric and magnetic fields. Construction and decommissioning of utility-scale solar energy facilities would involve a variety of possible impacts normally encountered in construction/decommissioning of large-scale industrial facilities. If new electric transmission lines or related facilities were needed to service a new solar energy development, construction, operation, and decommissioning of the transmission facilities could also cause a variety of environmental impacts.
Chapter 7 Waste management
Battery Recycling reduces environmental pollution With over 15 billion batteries sold in North America every year, we do not wish to be reminded of the ugly sight of that many batteries falling into landfills, to be buried with other trash. It makes more sense to 1. Use fewer batteries by recharging when possible, particularly in the case of ordinary alkaline batteries. 2. Save used batteries in containers, to be taken to nearby recycling depots. 3. Collect used batteries to take to hazardous material collection locations. 4. Pay attention to the proper disposal of the types that cause the most environmental damage: Nickel-cadmium batteries and lead-acid batteries. 5. Make use of plants specifically designed for the purpose to recycle metals and other materials used in batteries. Lead-acid batteries used in automobiles and motorcycles are easy to identify by their size and weight and unique heavy metal terminal lugs. Lead-acid batteries are also found in burglar alarms, computer power supplies as sources of uninterrupted power during blackouts, and emergency lighting units. The batteries are almost always properly labeled so you can determine what type of battery they are. Nickel-cadmium batteries, on the other hand, are not always labeled as such. They are most often found in portable telephones in the home, in razors, in electric drills and power tools. When in doubt, treat the battery as hazardous and take it to a center capable of proper disposal.
Recycle速 is the only free rechargeable battery and cell phone collection program in North America. Since 1994, Recycle has diverted 50 million pounds of rechargeable batteries from the solid waste stream and established a network of 30,000 recycling drop-off points. Advancing green business practices and environmental sustainability, Call2Recycle is the most active voice promoting eco-safe reclamation and recycling of rechargeable batteries and cell phones. Call2Recycle is operated by the non-profit Rechargeable Battery Recycling Corporation (RBRC). Program Funding Recycle is funded by product manufacturers across the globe committed to environmentally-sound recycling of rechargeable batteries and cell phones. These manufacturers, representing 90% of the rechargeable power industry, place the RBRC recycling seal on their rechargeable products and batteries, letting users know that the batteries need to be recycled rather than thrown in the trash. Recycling Partners Recycle partners with thousands of businesses, communities, and retailers to offer battery and cell phone drop-off points. Business Partners Recycle's business partners use rechargeable products in the field and in their offices everyday. They set up Recycle collection boxes to recycle the resulting waste. Community/Public Agency Partners Recycle helps communities and public agencies operate curbside pick-up and household battery and cell phone collection program.
Retail Partners Recycle's retail partners provide easy access for customers to drop off their used batteries and cell phones for recycling. Participating retailers include (in the U.S.): AT&T, Best Buy, Black & Decker, DeWalt, The Home Depot, Lowe’s, Milwaukee Electric Tool, Office Depot, Orchard Supply Hardware, Porter-Cable Service Centers, RadioShack, Remington Product Company, Sears, Staples, Target,
US
Cellular,
and
Verizon
Wireless.
Participating retailers in Canada: Batteries Experts, Battery Plus, Bell World, Black & Decker, Canadian Tire, FIDO, Future Shop, The Home Depot, Home Hardware, London Drugs, Personal Edge/Centre du Rasoir, Sears, The Sony Store, The Source by Circuit City, Staples, Telus Mobility, and Zellers. Government Support In May 1996, Congress enacted Federal legislation known as the Mercury-Containing and Rechargeable Battery Management Act. This Act streamlines state regulatory requirements for collecting Ni-Cd batteries and encourages voluntary industry programs to recycle them. The RBRC program has received recognition, endorsements, and awards from the U.S. Conference of Mayors, Keep America Beautiful, Canadian Council of Ministers of the Environment, and The Home Depot. The RBRC Battery Recycling Seal has been certified by the U.S. EPA. Federal and State Recycling Laws Federal, state and provincial regulations govern the proper disposal of rechargeable batteries and cell phones. Call2Recycle is named in official legislation as the collection method for eco-safe rechargeable battery and cell phone recycling. What's New Call2RecycleÂŽ is proud to unveil our new collection box. The new and improved design makes it more eco-friendly and easier to use. Please continue using the old box as we transition to the new collection kit.
Recycling at Home Call2Recycle offers consumers a free and easy way to care for the environment through its nationwide battery and cell phone recycling program. It's easy and free to recycle your old cell phones and rechargeable batteries from your cordless electronic products. Just follow these three easy steps. Step 1: Look for your rechargeables If it's rechargeable, it's recyclable. Look for used rechargeable batteries and old cell phones in your home that are dead or not being used any longer. Rechargeable batteries can be found in cordless electronic products that you plug in to get recharged. Use our handy tool to help find them all!
Step 2: Find a recycling location Find the recycling location nearest you and drop off your used rechargeable batteries and old cell phones. Step 3: You’re done! It's that simple! Now the store will ship the rechargeable batteries and cell phones to our recycling facility. Please go to our FAQs to find out what materials are reclaimed during the recycling process.
Recycling at Work Call2Recycle has free programs for retailers, businesses, communities, and public agencies. These groups collect used rechargeable batteries and old cell phones, and ship them to our recycling facility. We reclaim reuseable materials: nickel, iron, cadmium, lead, and cobalt from the batteries. A portion of the proceeds from resale of refurbished phones benefits select charities.* Step 1: Sign up online Once you sign up, we will send collection boxes with pre-paid, preaddressed shipping labels, safety instructions and plastic bags for used rechargeable batteries and old cell phones. Retailers and community recycling centers open to the public will be listed on our zip code locator and toll-free helplines to encourage residents to recycle. (Public agencies and businesses will not be listed.) Step 2: Start collecting Place rechargeable batteries and cell phones with or without battery individually in the Call2Recycle plastic collection bag, and then into the box. If you're running low, order more boxes or bags (or tape battery terminals with non-conductive electrical tape if you don’t have plastic bags). Use our promotional materials to help get the word out to your customers and community. Step 3: Ship the box Once your box is full, ship it to the recycling facility. Make sure that each battery is bagged (if plastic bags are unavailable, cover battery terminals with tape – electrical, duct or masking). Remember: ONE rechargeable battery or ONE cell phone with battery per bag only. We pay for the shipping and recycling costs and send you a new box. *contributions or gifts to RBRC are not tax deductible
Chapter 8 Findings :
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From the global experience, it has been observed that solar power is economically viable for distant rural electrification program which upgrades the living standard of the rural mass. This fact has also been fully endorsed by Rural Electrification Board (REB), state-own utility devoted on rural electrification in Bangladesh since 1978. A large portion of the remote areas are not likely to be covered by the grid network due to inaccessibility and low consumer density Renewable Energy Technologies like solar,biomass are considered as viable technical options for remote off-grid areas. Deploying RETs will not only provide electricity, it will become a stimulant for other development activities,like poverty alleviation, health care, education, women empowerment, family planning etc. Among the renewable resources, only in solar power do we find the potential for an energy source capable of supplying more energy than is used. Combating Greenhouse Gas Emissions Bangladesh is most vulnerable to sea-level rise. The population is already severely affected by storm surges. Catastrophic events in the past have caused damage up to 100 km inland Even a very cautious projection of 10 cm sea level rise, which would most likely happen well before 2030, This will inundate 2500 sq. km, about 2% of the total land area On average, the sea would move in about 10 km, but in the Khulna region, the sea will likely move in further With the high end estimates, sea level rise in Bangladesh would inundate 18% of the country by 2100. So, Bangladesh should encourage clean RETs to combat greenhouse gas emissions to avert the potential threats. Trends of Solar power using are increasing tremendously
It is hard to imagine to what extent these catastrophes would be with accelerated sea-level rise. In figure
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Millions of different types of battery being dumped in the world and in Bangladesh, at present there 230000 SHS’s and the number is expected to 1 million by 2015 . Normally within 3-5 years most of the SHS’s experienced changing their batteries. No concentrating thermal generation system in Bangladesh. Many countries in the world are installing concentrating thermal generation plant.
Assessments about impact of the rural electrification program in Bangladesh are the following • 93.7% of the electrified households reported decrease in fuel cost. • 78.2% reported an increase on working hours. • 62.0 % reported an increase in household income • 81% reported an increase in reading habits • 93.7% reported an increase in children’s study time. • 92.0% reported an increase in amusement as well as standard of living. •
94.7% reported an improvement in security
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Chapter 9 Recommendation , Warning and Conclusion Recommendations : Solar is highly compatible with the values and desires of the environmentally-conscious citizen." A government study from the Department of Energy (DoE) & National Renewable Energy Laboratory (NREL) concluded the following about Solar Energy: "Solar electricity is clearly a wise energy investment with great environmental benefits!" The Major Objectives of Sustainable Energies The conservation of fossil fuels, the reduction of pollutants, reduction of waste, and higher efficiency usage of electricity are the main environmental objectives to which Solar achieves each of these ends. The Conservation of Fossil Fuels This is a simple, yet important effect of using Solar Energy. As more and more individuals, corporations, and government use alternative energies such as solar, we conserve fossil fuels and other natural resources that are quickly diminishing. With a rapidly expanding world economy, and the strong growth in highly populated countries - the demand for energy is increasing at an alarming rate. This makes conserving our resources more important than ever. In addition to the deterioration of land, air and water - the rapid depletion of natural resources “further compromises the ability of future generations to meet their own needs”. The Reduction of Pollutants
Electricity production in Colorado is dominated by fossil fuels—98% coal, 2% petroleum and other like fuels. Overall energy production (heat, electricity, etc.) is also dominated by these fuels (51% coal, 16% natural gas and 3% petroleum). The resulting CO2 emissions come from coal (81%), gas (15%), and from petroleum (4%). There are major environmental impacts attributed to electricity generation from these non-renewable fuels. Emissions of pollutants into the atmosphere (particulates, Sulphur Dioxide (SOx), Nitrogen Oxide (NOx), Carbon Dioxide (CO2), and others) all have a grave impact on public health, water and crops. These negative externalities also impact many delicate ecosystems such as forests and fisheries. The Reduction of Waste Electricity produced from Coal (the primary source of electricity) results in a great deal of waste during the process, such as: • • • • • •
Mining: Dust from surface mining, Drainage Water Cleaning and Drying: Liquid and Solid Waste, Dust and Coal Fines (30 tons) Transportation: Spillage, Dust and Fines Storage: Liquid Drainage, Dust and Fines Power Plant: Liquid and Solid Waste (5000 tons of liquid; 360,000 tons of solid ash), Emissions (150,000 tons of mainly SOx, NOx, CO2, and particulates) Water, Land, Energy, and Heat are also wasted over the entire process of converting coal to electricity
Nearly every type of energy production from non-renewable sources produce wastes which have a negative impact on the environment. Even nuclear energy, while burning relatively clean, presents serious problems with the safe storage of radioactive waste and the possibility of widespread nuclear fallout from a reactor meltdown. Higher Efficiency Usage of Electricity The efficiency of fossil fuel electricity generation is stunningly low. Given that the amount of the fuel (coal, petroleum, natural gas, etc.) is growing scarce, this lack of efficiency is all the more important. When you burn these fossil fuels to create electricity, we only convert about 35% of the energy produced into electricity, the other 65% is lost mostly in heat. It is now wonder why these fuels are quickly disappearing. While the efficiency is low for the individual solar cells themselves, the Solar Energy system is quite efficient. That doesn't much matter however, since the fuel for Solar Energy (the Sun) is virtually limitless and available worldwide.
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It will be fatal disaster if storage battery waste can not be controlled with increased the trend of using solar energy . Acid from the battery will seriously affect the water and soil and air. Agriculture productivity will be seriously hampered. Poisonous metal lead will be mixed with water and soil and air. Awareness campaign to started from now for safe damping..
Conclusion
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Bangladesh has got ample solar insolation throughout the country. Daily average solar radiation varies between 4 to 6.5 kWh/m2. Maximum amount of radiation is available on the month of March- April and minimum on December-January. There is bright prospect for applications of solar thermal and photovoltaic systems in the country. All Non-renewable have emission which global warming and destruction to environment All renewable energy need external source but solar absolutely independent. Among all energy solar is less polluting Among all energy solar is less costly Of all the energy sources available, solar has perhaps the most promise. Solar energy is free, No one regulates sunlight, it's already ours. Recycle , recaharge, reuse battery Campaign for green energy Campaign for waste disaster At present has no concentrating panel system so initiatives to be taken to install concentrating solar thermal generating system.