SMART THINKING FOR A SMARTER LIVING – An Attempt to transform our habitat for a better healthy living. Neelu Ravi Marigoudar
Department of Architecture, Masters in Sustainable Environmental Systems, Pratt Institute, 200 Willoughby Ave, Brooklyn, USA 11205.
Abstract In view of the present and future energy needs, the building design should be well integrated with energy efficient techniques and strategies – especially solar energy either solar active or passive technique to reduce the energy loads. The term paper is to address the active solar techniques in the built environment while understanding the criterion for sustainability in the built environment. The main questions I would like to address in this term paper are; •
Why solar energy associated with the built environment in particular?
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In what form or How can it be used?
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How efficient is the technology when incorporated in the built environment? And
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How economical and efficient is it?
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What is the future of the built environment with this technique?
The amount of energy consumed varies depending on the design of the fabric of the building and its systems and how they are operated. For this reason, energy efficiency in buildings is a prime objective at global levels. Framing regulations to incorporate one or few of the renewable energy methods such as solar or wind or thermal energy or all of them, within the building will help us make a stride towards better, healthier and smarter living. As global energy demand continues to grow to meet the needs of people across the globe, actions to increase energy efficiency in the built environment will be essential. However, these improvements to be aimed and designed to be holistic in such a way as to they cater to much futuristic needs rather than serve for time being.
1. WHAT IS SUSTAINABLE ARCHITECTURE? Sustainable design as I understand is the action to take against the greed of man. The greed depletes resources, but sustainable development is like a practice of renunciation. It is the challenge of meeting the growing human needs for natural energy resources in the form of industrial products, food, transportation, shelter and effective waste management while conserving and protecting earth’s natural physical, chemical and biological systems and resources for future life and development. The energy consumption and its effect on the climate have rapidly increased for the last few decades. Sustainable Architecture is the conscious approach to the design of buildings keeping into consideration the energy consumption and user’s comfort level. The key factors which influence the design of sustainable buildings are beauty and inspiration, materials, site, Marigoudar Neelu
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energy, water and indoor quality. A sustainable building design can be considered to have made the buildings liveable; hence we can call such buildings as ‘Living buildings’. The living buildings use zero net energy and water on annual basis.
Fig 1: Factors affecting sustainable building design. 2. WHY BUILDINGS? The purpose of a building is not only to provide shelter for its occupants, but also to provide an environment conducive to high performance of all intended occupant activities. These buildings which are the foundations of a city around the world in developed and developing countries, consume a major amount of energy and natural resources, creating very serious problems for the sustainability of our natural environment. The amount of energy consumed varies depending on the design of the fabric of the building and its systems and how they are operated. For this reason, energy efficiency in buildings is a prime objective at global levels.
Fig 2: Life cycle phases of buildings.
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The biggest trick with the buildings is that they consume a lot of energy from their very basic pre design stage until their demolition and even after demolition most of the times. Addressing the energy consumption issues at this each of the stages has become a herculean task. The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) estimated that between 1970 and 2004, global greenhouse gas emissions due to human activities rose by 70 percent (IPCC, 2007). It is estimated that at present, buildings contribute as much as one third of total global greenhouse gas emissions, primarily through the use of fossil fuels during their operational phase.
Fig 3
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3. WHY SOLAR ENERGY WITH THE BUILT ENVIRONMENT? From the ancient times, every living being is dependent on solar energy either in the form of heat or radiant light from the Sun. Perhaps the use of solar energy has been by default, by all the ancient civilizations across the globe. The solar energy has been in use ever since the beginning of the 7th Century B.C. and 18th Century, in the form of passive solar technique and active solar technique respectively (Ref. Fig 5). The Fig 5 below shows the various scientific inventions with respect to solar passive and active techniques throughout the different stages of development of science.
Fig 5: Development of Active and Passive solar energy
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In the façade of the global warming challenge, solar energy holds massive potential for meeting humanity’s energy needs over the long term while wounding greenhouse gas emissions. Solar energy has recently become a rapidly growing source of electricity worldwide, its advancement aided by government support across the globe. As a result the solar industry has become global in important respects.The main advantages of incorporating solar energy with the built environment are that it is the world wide availability of it and as we all know Sun is free. It has low or no environmental impacts due to its use which is the main positive outcome of using this energy. When compared to all the other alternative energy sources, it is more efficient. Technology has been is continuous development to find various methods to store this energy for future timely effective uses. Even though this technology has a major installation and initial investment cost, the low maintenance during its operational stages outweighs this con side of the technology.
Table 1: Comparison of renewable energy sources [6, page 31, 7] “In Table 1 basic criterion are collected to get a better overview of the main characteristics of each source. The overall status of solar energy is positive because of the high amount of energy available, variations of gained energy types and low impact on environment. Very important, in this case, is the establishment in small scale, in means of good possibilities to use this source for personal use. The price factor shows the average Marigoudar Neelu
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situation now, but it is variable with the tendency to decrease for most of the sources with the lapse of time. The main disadvantage on the background of other energy sources is the supply frequency – solar energy is weather dependent”. (Dagne Vilka November 2010, 11) 4. DESIGN APPROACH TO MAKE BUILDINGS SUSTAINABLE. The conclusion that we can derive after understanding the importance of solar energy with the built environment (i.e. Section 3 of the report) when compared to any other alternative energy sources is that, Solar energy technologies are a potent solution to reduce the environmental damage caused by our dependence on fossil fuels . This technology which works on three basic principles of energy consumption namely; collection, storage and distribution of the sun’s energy, can radically reduce our use of fossil fuels and our emissions of global warming pollutants such as greenhouse gasses. Hence, the integration of this technology with the built environment at various levels of the project makes it successful. There are many types of solar technologies that can be adapted in our energy systems namely, Passive solar technique, Active solar technique and Hybrid technique. I.
Passive Solar Technique: This technique includes integration of all the professionals who are responsible for the building design as well as for the systems operation. A passive solar building makes the greatest use of orientation towards the sun and attains possible solar gains to reduce energy use for heating and cooling. By using natural energy flows and materials with favourable thermal mass or light dispersing properties—radiation, conduction, absorbance and natural convection buildings are made liveable.
I.
Active Solar Technique: This is one of the major technologies to obtain energy efficiency in buildings from Sun. This system operates by mechanical means such as photovoltaic panels and thermal collectors to collect the energy from sunlight convert the energy to useful forms of energy and distribute that energy form to support building service operations within the building.
II.
Hybrid Technique: “Hybrid power systems combine two or more energy systems or fuels that, when integrated, overcome limitations of the other, such as photovoltaic panels to supplement grid supplied or diesel-generated electricity. Hybrid systems are the most common, except for the direct gain system, which is passive”. (Robertson and Athienitis, 2) (Canada: CMHC, 1998) Canada Mortgage and Housing Corporation (CMHC)
5. ACTIVE SOLAR TECHNIQUES IN BUILDINGS. Active systems consist of solar collectors, a storage medium and a distribution system. “Active solar systems convert the solar energy, with help of different technologies, to useful energy that can be used to support the building service systems. The electromagnetic radiation emitted by the Sun can be converted in an active way in two main energy types – electricity and thermal energy. Exactly these are the two types that buildings (residential 37% and commercial 35%) are consuming the most (Figure 15 and 16). Mainly energy is used for space heating, lighting and support of electrical equipment. ” (Dagne Vilka, November 2010, 20) Marigoudar Neelu
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Active solar systems are commonly used for water heating, space conditioning, producing electricity, processing heat and solar mechanical energy. While we all have seen and experienced solar water heaters and solar cookers in our homes, we need to consider the major pie of the energy consumption that is space heating. Electricity can be produced by either direct or indirect methods by using solar energy namely; Photovoltaic systems, Photo-electrochemical systems, solar thermal systems, solar thermoelectric systems, Solar cooling and other applications. 5.1 Photovoltaic systems: This system uses the direct process to covert solar energy into electricity by the use of solar photovoltaic cells. “It occurs when specific materials are affected by sunlight and electric current is generated.” (Dagne Vilka, November 2010, 21) The exchange of electrons in an atom is called the flow of electricity which is the electric current. In the solar cells, there is also flow of electrons similar to the one mentioned above but only a little more complicated. “When sunlight strikes a photovoltaic cell, electrons in a semiconductor material are freed from their atomic orbits and flow in a single direction. This creates direct current electricity, which can be used immediately, converted to alternating current or stored in a battery. Whenever sunlight arrives at its surface, the cell generates electricity. PV cells normally have a lifespan of at least 20-25 years; however, they usually last longer if frequent overheating—temperatures in excess of 70ºC (158ºF) is prevented.” (Robertson and Athienitis, 27) (Canada: CMHC, 1998) Canada Mortgage and Housing Corporation (CMHC)
Fig 7: Working of a PV Cell
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5.1.1 Types of Photovoltaic (PV) solar cells: PV cells are much in commercial use because of the availability of the various types based on the material used in their manufacture as well as based on their working pattern. Based on their working pattern there are two types of PV cells, namely; Autonomous PV cells and Hybrid PV cells which work in combination with any other energy sources to produce electricity. The other types of PV cells are based on their material usage during their manufacture. These are of four types, namely; Single-crystalline or mono-crystalline cells, Multi-crystalline or polycrystalline cell, amorphous silicon cells and other thin films.
Fig 8: Difference between monocrystalline polycrystalline and amorphous thin film solar cells. 5.1.2 Photovoltaic (PV) solar systems in Buildings: The PV solar cells combined together to make solar panels. These panels alone cannot light up the entire building with electricity. Additionally other components are also required to complete the whole complex process of conversion of solar energy into usable electric energy. The other components used in this process help in transmission and storage of the energy when required. This entire component system can be designed in two ways – grid-connected or off-grid systems. Some potentials of Photovoltaic solar systems are that they are light weight and available in varied dimensions and thus easy to integrate in different parts of buildings. As we all are witnessing the vast amount of glass in skyscrapers and huge office buildings. The idea of generating solar energy from the window panels and glass facades of the buildings is gaining traction as these panels and facades form the major portion of the most of all the buildings in the big metropolitan cities. Correct and efficient usage of these is to generate one or the other forms of energy from the radiant solar energy on these panels. This is a very potential method which can be adapted in all the buildings in all the major cities of the world the design, installation and start-up of the PV solar system can be done in short time. This wades off the main concern of the designers and systems operation managers. Photovoltaic cells can be integrated in different roof systems too. Though, in developing stage of a project, integrating PV technologies in the design is little critical, there after maintenance becomes much easier. The buildings with PV solar systems obviate the use of fossil fuels or tapping of electricity from the regular grid systems by using solar energy for either of the purposes. This technology can be easily adapted in the new homes as well as in the existing buildings. Marigoudar Neelu
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In case of new buildings, solar energy can be made to implement right from the design stage in the form of passive solar technique and in the latter stage active solar technique can be incorporated. These new homes can be made ‘liveable’ where they consume zero energy from either the regular grid systems or the conventional methods. These Zero energy homes can be designed in such a way so that they produce as much energy as they consume. In case of existing homes, passive solar technique may not be in the scenario to be adapted as these buildings are not designed to trap the advantage of the sun. But definitely active solar energy technique can be incorporated either with the installation of PV solar cell systems or with the solar water heating systems. 6. FUTURE OF THE SOLAR TECHNOLOGY Solar energy can be integrated into virtually every part of human life - the homes we live in - Solar Homes, the offices where we work - Solar Businesses, the farms and factories that produce the products we buy - Solar Factories, the vehicles we drive - Solar vehicles. In order to motivate the public, governments across the globe are coming up with creative public policies to promote the adoption of solar energy at the individual, community, national and global scale. Many financial incentives in the form of cash or tax credits for solar power adaption have been brought into action.
7. CONCLUSION Across the globe, solar energy can be enormously gathered in various forms and by adapting various technologies. It’s just not about the futuristic design approach for a greener town or cities in which all the homes and buildings are designed to be energy efficient buildings; we should also aims at making the entire lifestyle a greener way to achieve a sustainable environment. This will not only increase the energy security of the country, but also make the country independent in having its resources. Framing regulations to incorporate one or few of the renewable energy methods such as solar or wind or thermal energy or all of them, within the building will help us make a stride towards better, healthier and smarter living. As global energy demand continues to grow to meet the needs of people across the globe, actions to increase energy efficiency in the built environment will be essential However, these improvements to be aimed and designed to be holistic in such a way as to they cater to much futuristic needs, where we can give our future generation the chance of life in a greater environment rather than serve for the time being.
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LIST OF FIGURES AND TABLES: 1) Fig 1 - Riley, 2010. “Design Manifestation of Environmental Philosophy: The Modern Nature Ethic and the Living Building Challenge” WordPress, April 11. Accessed December 01, 2015. https://johnstonarchitects.wordpress.com/ author/rileymacphee/page/33/ 2) Fig 2 - Graham, 2003. 3) Fig 3 - Mazria, E. (2003) "It's the Architecture, Stupid!" Solar Today, p. 49, May/ June. 4) Fig 4 - Mazria, E. (2003) "It's the Architecture, Stupid!" Solar Today, p.50, May/ June.
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5) Fig 5 - Vilka, Olesen, November 2010 “Active Use of Solar Energy in Buildings” Why How What Guide for the Architect, Architectural Technology and Construction Management. Elective Subject Dissertation., – final – 7th Semester, Vial University College – Campus Horsens November 2010). 6) Fig 6 - Vilka, Olesen, November 2010 “Active Use of Solar Energy in Buildings” Why How What Guide for the Architect, Architectural Technology and Construction Management. Elective Subject Dissertation., – final – 7th Semester, Vial University College – Campus Horsens November 2010). 7) Table 1: Comparison of renewable energy sources [6, page 31, 7] 8) Fig 7 - Google. 2015. “Working of a PV Cell.” Last modified April6, 2011. Accessed December 12, 2015. http://science.nasa.gov/science-news/science-atnasa/2002/solarcells/. 9) Fig 8 - Google. 2015. “Difference between monocrystalline polycrystalline and Amorphous thin film solar cell?.” Last modified November 6, 2015. Accessed December 12, 2015. http://www.solarcloset.com/understanding-solarequipment/difference-between-monocrystalline-polycrystalline-andamorphous-thin-film-solar-cell/.
BIBLIOGRAPHY 1) Vilka, Olesen, November 2010 “Active Use of Solar Energy in Buildings” Why How What Guide for the Architect, Architectural Technology and Construction Management. Elective Subject Dissertation., – final – 7th Semester, Vial University College – Campus Horsens November 2010). 2) Robertson, Keith, and Andreas Athienitis. "Solar energy for buildings." (2009). 3) Dave Levitan, “Will Solar Windows Transform Buildings to Energy Producers?” Yale environment360 Reporting, Analysis, Opinion and Debate, May 03, 2012 Report. 4) [4] “World Total Energy Production”, 28.10.2010. 5) Cobb. 2007. “Projecting World Energy Production.” The Quaker Economist, March 27, 2007. Volume 7, Number 155, Page 2. Accessed November 5, 2015. http://tqe.quaker.org/2007/TQE155-EN-WorldEnergy-2.html 6) Mazria, E. (2003) "It's the Architecture, Stupid!" Solar Today, p. 48-51, May/ June. 7) Marc Gunther, “Beyond Sprawl: A New Vision of The Solar Suburbs of the Future” Yale environment360 Reporting, Analysis, Opinion and Debate, September 21, 2015 Report. 8) Xiaohong Guan; SKLMS Lab., Xi”an Jiaotong Univ., Xi”an, China; Zhanbo Xu; Qing-Shan Jia, “Consequentialize This,” Ethics 121, no.4 (July 2011): 752, Browse Journals & Magazines > Smart Grid, IEEE Transactions > Volume: 1 Issue: 3, Energy-Efficient Buildings Facilitated by Micro grid. 9) P. Caputo, M. Molina, A. Roscetti and J. Vicari Accademia di Architettura di Mendrisio, Largo Bernasconi, Mendrisio, CH C. Milani, I. Rega and P. Schettino Marigoudar Neelu
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eLab, “ Ecology in architecture design: Testing an advanced educational path” (paper presented at the International Conference “Passive and Low Energy Cooling 299 for the Built Environment”, May 2005, Santorini, Greece). 10)Dahl, R. (2013) "Cooling concepts: alternatives to air conditioning for a warm world," Environmental Health Perspectives 121(1):A18-A25.
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