Energy sources

Sun is the source of most of the energy and derives its energy from nuclear synthesis of protons into helium on its hot core. Solar radiation can be converted to heat through thermal solar devices and to electricity through photovoltaic cells. But most of the supply of energy received from sun is available through various sources as noted below.Fossil fuels like petroleum crude, natural gas and coal represent a huge source of chemical energy and have their origin in biomass buried under the earth and fossilized millions of years ago. These fossil fuels meet most of the global energy needs.Animate Energy is the useful energy delivered by human and work animals. India’s dependence on animate energy is high as compared to the developed countries with respect to human labour and draught animals.
Biomass includes energy crops, agricultural residues, marine plants, by products of forestry, food and agro processing industries, animal by products and waste, etc. Trees and plants use light energy of sun to convert atmospheric carbon dioxide and water into organic compoundsby a process called photosynthesis.
Wind energy derived from wind is a major source of kinetic energy, wind mills, also called wind turbines , convert the kinetic energy of wind into mechanical or electrical energy depending on the attachment.
Hydro energy can be both potential and kinetic. Turbines and water wheels can be used to convert it into mechanical or electrical energy.
Ocean currents generated as a result of the temperature difference between surface and deep waters of tropical oceans represent a large source of energy. In addition to the renewable sources listed above, Geo thermal energy obtained from hot core of earth is a source of heat energy and is used in some countries for power generation through steam cycle.