Sources of Energy
Energy is the ability to do work. Energy comes from various sources and is available in many forms. According to law of conservation of energy states that energy can neither be created nor be destroyed but it can be transformed from one form to another. The specific sources which provide various forms of energy are called sources of energy. A good source of energy is one which does a large amount of work per unit volume or mass. It should be easily accessible, easy to transport and economical.
Sources of energy are classified as conventional and non-conventional sources of energy. The conventional sources of energy are those sources which are being used since a long time and do not replenish in a short period of time.
Fossil fuel in the form of coal, petroleum and natural gas is major conventional source of energy. Fossil fuels should be used in a sustainable manner as these are non renewable sources of energy and also cause pollution.
Thermal power plants use coal to generate electricity. Hydro power plant and wind energy are some important conventional sources to generate electricity. In hydro power plant the fast moving water (kinetic energy) strikes the turbines and turbines start moving (mechanical energy) and then this energy is used to run electric generators. For harnessing wind energy, wind mills are constructed.
The shaft connected to the rotating fans due to high speed, winds rotates the turbine which is used to run electric generators. Bio-mass produces methane which is used as a fuel or for generating electricity at domestic levels by decomposing plants and animals excreta in the absence of oxygen. Bio-mass is also known as gobar-gas.
Tidal energy, wave energy, solar energy, geothermal energy, and nuclear energy are of non-conventional sources of energy. All these sources are renewable or inexhaustible and do not cause environmental pollution.
Solar cookers and solar cells are the devices that convert solar energy into electricity. A large number of solar cells, combined in an arrangement is called solar cell panel. Energy from waves and tides are used to rotate a turbine for generating hydro electricity. In geothermal power plants, steam is pumped out with the help of pipes and rotates the turbine for the production of electricity.
Nuclear energy is produced by the processes of nuclear fission and nuclear fusion but only nuclear fission is used to generate electricity as nuclear fusion is uncontrollable. Nuclear fission is the process in which the nucleus of a heavy atom is split into two lighter nuclei when bombarded by a neutron liberating an enormous amount of energy.
Exploiting any source of energy disturbs environment in some way or the other. The use of energy beyond the limit will lead to energy crisis.