Renewable energy is energy from a resource that is replaceable by existing flows of energy, such as sunshine, wind, water, biological processes and geothermal heat flows. These energy resources might be used directly or indirectly as forms of energy. The contemporary interest in renewable energy is linked to the exhaustion of fossil fuels and environmental challenges created by the use of fossil fuels and nuclear energy. However, the burning of biomasses for heat and light have been exhausting natural resources for centuries, but the oil crisis and the green house effect have been strong motivations for the expansion of renewable energy.
The main renewable energy sources are Solar, Wind, Water, Geo thermal, and Biomass.
Solar energy is energy of the sun. It comes in the form of heat and light. And this can be converted to both electrical and mechanical energy.
Wind energy is converted into other useful forms of energy such as electrical energy with the help of wind turbines or wind-powered generators.
Water energy like wind energy is also converted into electrical energy by using hydraulic power plants.
Geo thermal energy is heat from within the earth. We can use the steam and hot water produced inside the earth to generate electricity or heat buildings.
Biomass is organic material made from plants and animals. Some examples of biomass fuels are wood, crops, manure, and some garbage. Biomass fuels are burned to produce steam for making electricity, or to provide heat to industries and homes.
India is one of the largest and fastest growing economies in the world, as well as an expansive populace of above 1.1 billion people. There is a very high demand for energy, which is currently satisfied mainly by coal, foreign oil and petroleum, which apart from being a non-renewable, and therefore non-permanent solution to the energy crisis, it is also detrimental to the environment. The price of crude oil has risen sharply over the last few years, and there are no signs of a change in this trend. Thus, it is imperative that India obtains energy security without affecting the booming economy, which would mean that alternative energy sources be found. This would mean that the country must switch from the nonrenewable energy - crude oil and coal - to renewable energy.
India is determined to becoming one of the world's leading clean energy producers. The Government of India has already made several provisions, and established many agencies that will help it achieve its goal. Renewable Energy, excluding large hydro projects already account for 9% of the total installed energy capacity, equivalent to 12,610 MW of energy. In combination with large hydro, the capacity is more than 34%, i.e. 48,643MW, in a total installed capacity of 144980 MW.