More then 90% of the energy that is spent this day comes from non-renewable sources. The main reasons why people use non-renewable sources are because they don’t know the alternatives or the alternatives are too expensive.
So let’s highlight some of the renewable energy sources:
Hydropower:
Energy can be produced by channelling the flow of rivers or by storing water in reservoirs behind dams and directing it through turbines. This doesn’t cause any pollution, Hydropower is clean and renewable, yet it supplies less than 20 percent of the world's electricity.
But not everything is good about Hydropower, dams disrupt river ecosystems. It affects many habitats and can make it impossible for certain fish such as salmon to travel upstream to spawn. Fortunately technology doesn’t stand still and in the article about “Ending a dammed nuisance” you can read how they are trying to get rid of this.
Solar Energy:
Since centuries people use sunlight to cook food, heat water and homes. Today, solar energy is used for more then just those purposes. For example it’s used to provide hot water for industries such as laundries. Also well known are the solar panels, in sunlight these panels generate electricity. This is also clean/renewable energy, but the cost of solar panels is still too high.
Wind Energy:
This is now one of the fastest-growing energy sources worldwide. The tall wind turbines make use of the wind to generate electricity. The problem with wind mills is that they may cause environmental concerns. However it’s also a clean and renewable energy source.
Geothermal Energy:
Geothermal energy is probably not very well known. It comes from intense heat within the Earth, which also produces hot springs, geysers, and volcanoes.
The only widely used type of geothermal energy is hydrothermal, this is produced when subsurface water contacts hot rock and turns to steam, which is piped to the surface. In a geothermal electric plant, steam is piped to a turbine to power an electrical generator.
This type of energy doesn’t produce pollution when used, but to generate this energy there’s a lot of oil and gas needed especially for getting this energy above the ground.
Bio fuels:
This is now one of the fastest-growing energy sources worldwide. The tall wind turbines make use of the wind to generate electricity. The problem with wind mills is that they may cause environmental concerns. However it’s also a clean and renewable energy source.
Geothermal Energy:
Geothermal energy is probably not very well known. It comes from intense heat within the Earth, which also produces hot springs, geysers, and volcanoes.
The only widely used type of geothermal energy is hydrothermal, this is produced when subsurface water contacts hot rock and turns to steam, which is piped to the surface. In a geothermal electric plant, steam is piped to a turbine to power an electrical generator.
This type of energy doesn’t produce pollution when used, but to generate this energy there’s a lot of oil and gas needed especially for getting this energy above the ground.
Bio fuels:
Crops can be fermented to produce liquid bio fuels, the most common of which are ethanol and methanol. Today these alcohols are relatively high-cost but with the extremely high oil prices of today this can make them a good alternative. The air pollution savings from the increased use of ethanol are significant.
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