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Electricity explained  

Electricity is a secondary energy source

Electricity is the flow of electrical power or charge. Electricity is both a basic part of nature and one of the most widely used forms of energy.

The electricity that we use is a secondary energy source because it is produced by converting primary sources of energy such as coal, natural gas, nuclear energy, solar energy, and wind energy, into electrical power. Electricity is also referred to as an energy carrier, which means it can be converted to other forms of energy such as mechanical energy or heat. Primary energy sources are renewable or nonrenewable energy, but the electricity we use is neither renewable nor nonrenewable.

A hand unplugging an electrical appliance from an outlet

Source: Stock photography (copyrighted)

Sources of U.S. electricity generation, 2017: Renewables 17%, Petroleum 1%, nuclear 20%, coal 30%, natural gas 32%

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Electricity use has dramatically changed daily life

Despite its great importance in daily life, few people probably stop to think about what life would be like without electricity. Like air and water, people tend to take electricity for granted. However, people use electricity to do many jobs every day—from lighting, heating, and cooling homes to powering televisions and computers.

Before electricity became widely available, about 100 years ago, candles, whale oil lamps, and kerosene lamps provided light; iceboxes kept food cold; and wood-burning or coal-burning stoves provided heat.

Scientists and inventors have worked to decipher the principles of electricity since the 1600s. Benjamin Franklin, Thomas Edison, and Nikola Tesla made notable contributions to our understanding and use electricity.

Benjamin Franklin demonstrated that lightning is electricity. Thomas Edison invented the first long-lasting incandescent light bulb.

Before 1879, direct current (DC) electricity was used in arc lights for outdoor lighting. In the late 1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC) electricity, which reduced the cost of transmitting electricity over long distances. Tesla's inventions brought electricity into homes to power indoor lighting and into factories to power industrial machines.

Last updated: April 19, 2019