What Is Renewable Energy?

Man has always learnt lessons from his past and utilized them in the future. Over the last few centuries man has continued degrading the planet in everyway possible. Burning of fossil fuels like coal and crude oil releases a huge amount of harmful gases in the atmosphere. The most severe of them is carbon dioxide which prevents the heat from escaping, thus creating global warming. In addition to this the poisonous lead gases emitted by cars coupled with ozone depletion has seriously put the earth in peril. Thus man has recently concentrated all his efforts in finding out alternative sources of energy or renewable energy.

Renewable energy means energy from natural sources such as the sun, wind and water. There will always be a constant supply of these sources of energy and these do not add to the pollution in any way. All sorts of pollution like carbon gas emissions, chemical waste, radioactive and thermal pollution can be avoided if man can harness the power of these limitless energy resources. The various sources of renewable energy include several non-conventional sources of energy like the sun, wind, water, agricultural residue, firewood, animal dung etc. These resource are completely natural and far less polluting than the nonrenewable sources used now such as coal , crude oil and natural gases. There are several types of renewable energy. The energy harnesses from the rays of the sun is known as solar energy. Hydel power is the energy obtained from flow of water.

The energy trapped from hot dry rocks, magma, hot water springs, natural geysers, etc is known as geothermal energy and ocean thermal energy is derived from the ocean waves. In the cities crop residues, firewood, animal dung, etc can be burnt to produce energy and together they are called biomass.