The energy is derived from various sources on the basis of origin the energy can be derived from the renewable and non-renewable sources of energy. Renewable sources are those, which are abundantly available in nature and they can be replenished after a single use. For example, sunlight energy, wind energy, tidal energy, geothermal energy. But non- renewable sources are those which are available in limited amount hence, are expensive and cannot be replenished once they are used. For example fossil fuels such as coal, petroleum and natural gas. These are the resources which takes millions of years for their formation. Their genesis takes place inside the earth's geosphere under high heat and pressure conditions and by the action of the soil microbes acting upon the dead remains of plants and animals.
On the basis of the above description, energy resources that exist in limited amounts and, once used, cannot be replaced except over the course of millions of years are called non- renewable resources energy resources
