Natural gas, or simply gas in short, is a mixture of gases formed from fossilized dead plants and animals buried deep under the Earth's surface. Gas is mostly known for its role in cooking, heating water and in heating systems for buildings but is also used to produce electricity as well. Electricity is derived from natural gas in several ways, including through the use of combustion turbines similar to those of jet engines. This source of energy is the cleanest of all the fossil fuels.
Coal is known to be the most plentiful fossil fuel in the world. In the United States, more than 50 percent of electricity is produced by burning coal. In addition, coal is used for heating and cooking. The process of producing electricity involves heating water into steam using coal as the fuel. The steam is directed to drive turbine generators that produce electricity. However, burning of coal causes a great deal of pollution to the atmosphere.
Oil is a petroleum product that is pumped out of the ground in an unrefined form called crude oil. Electricity from oil is produced through burning a refined form of the oil to turn water into steam that drives electricity generating turbines; like natural gas, it also can be burned in combustion turbines to produce electricity.
Electricity from nuclear power is produced by reactors in nuclear power plants that use heat from the breakup of radioactive substances such as uranium to turn water to steam, which drives turbine generators. Uranium has to be mined and can be depleted. However, breeder reactors can create new nuclear fuels, so this form of energy is not strictly a non-renewable one. Nuclear energy accounts for about 11 percent of the world's power production.