Power Resources
Resources which give us energy are called power resources. There are two types of power resources, viz. conventional energy and non-conventional energy sources.
Sources of energy, which are in use since hundreds of years, are called conventional sources of energy. Energy sources which have come into use recently are called non-conventional sources of energy.
Conventional Sources
Firewood
It is the main source of energy in rural areas and is used as kitchen fuel. Collection of firewood is a tedious process. Combustion of firewood results in air pollution. Women who use firewood as kitchen fuel run the risk of getting respiratory diseases.
Coal
Coal is mainly used in industries. Coal is the fuel for most of the thermal power plants. Plants got buried in swamps millions of years ago. In due course of time, they got transformed into coal due to intense heat and pressure.
China, USA, Germany, Russia, South Africa and France are the leading producers of coal. In India, coal mines are present at Raniganj of West Bengal and at Jharia, Dhanbad and Bokaro of Jharkhand.
Petroleum
Petroleum is found in hollow layer between rocks. It is extracted by drilling deep wells. Crude oil is a black and viscous liquid. Due to its black colour and high economic value, it is also known as Black Gold. Crude oil is sent to refinery for further processing. Refining of petroleum gives various petroleum products, like petrol, diesel, kerosene, lubricant oil, paraffin, etc.
Iran, Iraq, UAE and Qatar are the leading producers of petroleum. USA, Russia, Venezuela and Algeria are other important producers. In India, petroleum is produced at Digboi in Assam, Bombay High in Mumbai and at Krishna Godavari Delta.
Natural Gas
Natural gas is found along with petroleum. It comes out during extraction of crude oil. Natural gas is an important fuel for industries and kitchen.
Russia, Norway, UK and Netherlands are the leading producers of natural gas. In India, natural gas is found at Jaisalmer, Krishna-Godavari Delta, Tripura and at some offshore sites of Mumbai.
Coal, petroleum and natural gas are called fossil fuels because they were made from fossils. Fossil fuels fulfill the major portion of our energy needs. But combustion of fossil fuels results in air pollution.
Hydro-electricity
In this method, electricity is produced by running turbines with the help of water current. For this, huge dams are made over river. Water is collected in reservoir before the dam. After that, water is released through sluice gates so that turbines can be moved. Water from dam is then released into canals so that it can be utilized for irrigation.
Hydro-electricity fulfills one-fourth of energy need of the world. Paraguay, Norway, Brazil and China are the leading producers of hydro-electricity. Major hydro-electricity projects in India are Bhakhra Nangal, Gandhi Sagar, Nagarjuna Sagar and Damodar Valley.
Making dams for hydro-electricity has severe environmental consequences. A huge area becomes inundated because of coming in the catchment area of the dam. This destroys flora and fauna of a large area. Thousands of people have to face displacement due to this.
Non-conventional Sources
Solar Energy
The sun has unlimited reservoir of energy. Now-a-days, electricity is produced with the help of solar panels. India is a country which gets plenty of sunshine for most of the months in a given year. This provides perfect condition for harnessing solar energy. Solar energy is environment friendly.
Wind Energy
Windmills can be installed at places which get decent wind speed. Wind farms for production of electricity have been made in western parts of India and also in Tamil Nadu.
Nuclear Energy
Nuclear fission of an element results in releases of huge amount of energy. Nuclear energy works on this concept. There are many nuclear power plants in India. Nuclear power plants enable us to produce more electricity with least expenditure. But a nuclear power plant always carries the risk of radiation leak. Radiation leak has long term deleterious effects on humans and other living beings.
Geothermal Energy
Molten magma is present below the crust of the earth. The heat from magma leaks out through fissures at certain places. This heat can be utilized to change water to vapour. The vapour can be then utilized to run turbine to produce electricity. New Zealand, Iceland, Philippines, Central America and Russia have started using geothermal energy. In India, geothermal power plants have been set up at Manikaran in Himachal and at Pugaghati in Ladakh.
Tidal Energy
When the tide comes, water level of sea rises. This can be blocked by making dams so that turbines can be run when water recedes. Tidal energy can be harnessed in coastal areas.
Biogas
The gas produced during decomposition of organic waste is called biogas. This gas is mainly composed of methane. Gobar gas plants are installed in rural areas. Organic waste (animal excreta, farm waste, etc.) is fed in gobar gas plant in the form of slurry. It is then left to decompose. The gas from gobar gas plant can be utilised as kitchen fuel and also for lighting purposes.