EDUCATION (CBSE/UGC NET)

Detailed explanation-1: -Primary energy sources take many forms, including nuclear energy, fossil energy–like oil, coal and natural gas–and renewable sources like wind, solar, geothermal and hydropower.

Detailed explanation-2: -Primary energy sources are generally classified as renewable or nonrenewable on the basis of whether they draw on a depleting energy resource. Fossil fuel is nonrenewable, whereas hydro, wind, solar, and wave power are generally treated as renewable.

Detailed explanation-3: -The energy of the sun is the original source of most of the energy found on earth. We get solar heat energy from the sun, and sunlight can also be used to produce electricity from solar (photovoltaic) cells.

Detailed explanation-4: -Energy of fossil fuels, solar radiation, or nuclear fuels, which are all primary, can be converted into other energy forms such as electricity and heat that are more useful to us. All energy that has been subjected to human-made transformation is secondary energy.

Detailed explanation-5: -Examples of renewable energy sources include wind power, solar power, bioenergy (organic matter burned as a fuel) and hydroelectric, including tidal energy.