Electricity is a flow of electrons and it is a secondary energy source, which means that we get it from converting other sources of energy, like coal, natural gas, oil, nuclear power, or renewable sources, into electricity.
How Electricity Is Generated
Most electricity is generated with steam turbines using fossil fuels, nuclear, biomass, geothermal, or solar thermal energy. The steam drives the turbine, which turns an electric generator to create electricity. Other ways to generate electricity include hydroelectric dams, wind turbines, and solar photovoltaic cells.
Fossil Fuels
Burning fossil fuels like coal, natural gas, and oil is the most common way to generate electricity. The U.S. Energy Information Administration (EIA) estimates that in 2019, about 67% of the electricity in the United States was generated by burning fossil fuels.
Coal is the largest source of electricity generation in the United States, but its share has been declining since 2007 because of competition from natural gas and renewables. In 2019, about 23% of U.S. electricity was generated from coal.
Natural gas is the second-largest source of electricity in the United States. In 2019, about 34% of U.S. electricity was generated from natural gas.
Oil is a smaller source of electricity generation in the United States than coal or natural gas. In 2019, about 1% of U.S. electricity was generated from oil.
Nuclear Power
Nuclear power plants use heat from nuclear fission in a contained environment to convert water to steam, which then drives turbine generators to produce electricity. In 2019, about 20% of U.S. electricity was generated by nuclear power.
Renewable Energy
Renewables are sources of electricity that do not deplete when used. The three main types of renewable energy are solar, wind, and hydro.
In 2019, about 17% of U.S. electricity was generated by renewables. This is more than double the amount generated in 2008. Solar and wind are the fastest-growing renewable sources of electricity.
Hydroelectric dams are the largest source of renewable electricity in the United States. In 2019, about 7% of U.S. electricity was generated by hydroelectric dams.
In the early 1800s, English scientist Michael Faraday discovered that when electricity flows through a conductor, it produces a magnetic field. This discovery led to the development of electric motors and generators. It also showed that electricity could be produced by moving a magnet through a conductor.
Now we know that electricity is a flow of electrons. Electrons are particles that orbit the nucleus of an atom. They are found in all matter. Electricity can be generated by natural sources like the sun and lightning, or it can be produced by man-made methods like burning fossil fuels or using nuclear reactions.
In the United States, about 4% of electricity is generated by solar power, 3% by wind and hydro, 10% by nuclear power, and the rest by burning fossil fuels like coal, gas, and oil.
The sun is the ultimate source of energy for our planet. Solar energy is captured in a solar cell and converted into electricity. The sun’s energy can also be used to heat up water, which can then be used to generate electricity in a process called solar thermal.
Nuclear power plants use the heat generated from nuclear fission to produce steam, which then turns turbines to generate electricity. Although nuclear power plants don’t produce greenhouse gases, the process of mining and enriching uranium can release these gases into the atmosphere.
Fossil fuels like coal, oil, and natural gas are formed from the remains of animals and plants that lived millions of years ago. These fuels are burned to produce heat, which is then used to generate electricity in power plants. Burning fossil fuels also releases greenhouse gases into the atmosphere.
Electricity is an essential part of modern life. It powers our homes, our businesses, and our industry. It is important to understand where it comes from and how it is generated.