introducing energy types

RENEWABLE ENERGY TYPES

LET’S TAKE A DEEPER LOOK AT THE DIFFERENT WAYS OF GENERATING ENERGY.

By: Chireez Fredericks

By supporting renewable energy and energy efficiency measures, The South African National Energy Development Institute (SANEDI) suggests that South Africa will foster a greener economy. We learn more about the types that are currently being explored in the country.

Go solar

Solar energy is one of the most commonly used renewable energies as it is derived by capturing radiant energy from sunlight. This sunlight is then converted into heat, electricity, or hot water! Solar energy could render fossil fuels obsolete as one of the benefits of solar energy is that sunlight is functionally endless. According to Thomas Hugo, a sustainability engineer & energy modeller from Ecolution Consulting, although solar energy will save us money in the long run, there tends to be a significant upfront cost and it is an unrealistic expense for most households. For personal homes, homeowners also need to have ample sunlight and sufficient space to arrange their solar panels, and this in turn limits who can realistically adopt this technology at an individual level.

Winding up

Wind farms capture the energy of wind flow by using turbines and converting it into electricity. Investment in wind energy technology can also open new avenues for jobs and job training, as the turbines on farms need to be serviced and maintained to keep running. However, according to The Office of Energy Efficiency and Renewable Energy (EERE), wind energy often needs to be transported via transition lines which are very costly as wind farms tend to be built in rural or remote areas, far from the cities where the electricity is needed most. Although wind turbines produce very little pollution, they may threaten local wildlife like birds, which are sometimes killed when striking the arms of the turbine while flying.

Hydro hero

Dams are what people most associate hydroelectric power with. Water flows through the dam’s turbines to produce electricity known as “pumped-storage hydropower”. Although hydroelectric power does not pollute the air, it disrupts waterways and negatively affects the animals that live in them, changing water levels, currents and migration paths for many fish and other freshwater ecosystems.

Heating up

Geothermal heat is heat that is trapped beneath the earth’s crust from the formation of the earth 4.5 billion years ago, and its radioactive decay. We can produce geothermal energy by capturing this heat and making use of the steam that comes off the heated water that pumps below the surface, which then rises to the top of the earth surface and can be used to operate a turbine. Geothermal energy is not as common as other types of renewable energy sources, but it has a significant potential for energy supply. Cost plays a major role when it comes to the disadvantages of geothermal energy. Not only is it costly to build the infrastructure, another major concern is its vulnerability to earthquakes in certain regions of the world.

Wave wonders

Dr James Joubert, sustainability engineer & energy modeller at Ecolution Consulting, states that wave energy is, in essence,

a concentrated form of solar energy. The sun heats the atmosphere, thus creating a wind that blows over the ocean surface and creates waves. Mankind has been trying to harness the energy of waves for many years, but the ocean environment is hostile, corrosive and an expensive place to build and install complex machines. It is expected that wave energy will be contributing significantly to certain niche markets such as island communities, desalination and aquaculture in the next few years.

Turn the tide

Tidal energy, on the other hand, is a result of the attraction force of the moon and sun on the earth and the ocean. It is highly predictable, with one being able to know the expected tidal range many years into the future. The largest and most successful examples of tidal energy generation are in Korea and France with their use of tidal barrage technology. There are limited available sites in the world for this kind of technology and it has a big environmental impact because tidal energy systems are built in an estuaries, which are sensitive and important ecosystems.

Biomass benefits

Biomass is organic matter that comes from living plants and organisms. An example of biomass that most people are familiar with is the wood used in a home fireplace. There are various ways in which one can generate biomass, such as burning biomass or harnessing methane gas which is produced by the natural decomposition of organic materials in ponds and landfills. The use of biomass in energy production releases carbon dioxide that is then consumed by regenerating plants. This is believed to create a balanced atmosphere. There are numerous ways to make use of biomass in our daily lives, not only for personal use but for businesses as well. However, despite new plants needing carbon dioxide to grow, their growth is a long process and biomass energy cannot compete with larger fossil fuel plants that are able to produce energy more rapidly.

Did you know?

André Harms – founder, director and sustainability engineer at Ecolution Consulting – suggests we also take into consideration the space and land needed to harness the energy from these various renewable sources. Making use of existing spaces and constructing spaces rather than just taking up land is the future-first kind of thinking needed in the developing world of renewable energy. An example of these existing spaces could be solar roofing panel technologies currently being explored by Solarcity and Tessla.