Subject:- Renewable Energy Sources

Topic:- Introduction to Energy Sources

Difficulty:- High

Energy Sources may be classified as

I. Primary and Secondary Energy Sources :

• Primary energy sources are those Which are found or stored in nature

• Examples: Coal. Oil, natural gas & biomass like wood.

• Examples of other primary energy sources as found on earth are nuclear energy from radioactive substances, geothermal energy , potential energy due to earth’s gravity etc.

• Secondary energy sources are usually converted from oil ,natural gas or coal.

II. Commercial & Non Commercial energy sources

• The energy sources that are available in the market & Which can be purchased at a definite price from the producing agency are known as commercial energy.

• The most important & high grade form of commercial energy are electricity, coal & refined petroleum products .

• Commercial energy forms the basic of industrial, agricultural, transport & Commercial development in the modern world .

• The energy sources that are not available in the Commercial market for a price are called as Non Commercial energy.

• Non Commercial energy sources include fuels such as firewood, cattle dung & agricultural wastes which are traditionally gathered & not bought at a price used especially in rural household these are also called traditional fuels.

III. Renewable & non renewable energy sources.

• Renewable energy is energy obtained from sources that are essentially inexhaustible.

• The most importance feature of renewable energy is that it can be harnessed without the release of harmful pollutants.

• Example of renewable resources include wind power, solar power, geothermal energy , tidal power & hydroelectric power.

• Non-renewable energy is the convential fossil fuels such as coal, oil, gas & nuclear energy. This from of energy is exhaustible & likely to deplete with passage of time.