Where Does Electricity Come From?

Ever wondered how exactly electricity is produced? Most electricity in the United States is produced by converting kinetic energy (energy of motion) into mechanical energy via steam turbines. The steam is forced against the turbine blades, in turn causing a generator shaft to turn and generate an electric current. Several different fuel resources are used to generate electricity, though some are nonrenewable and will eventually run out.

Coal and Petroleum

Both are burned either for producing steam, or at extremely high temperatures, producing combustion gases that again spin the blades that in turn spin the turbine shaft. Coal is a nonrenewable fossil fuel, meaning that it takes million of years to form from the trapping of dead plant energy, so there is a constant need to find new resources to mine. Petroleum is similar to coal in the sense that we cannot make new resources, but petroleum production also requires the trapping of organic material in oil-rich rocks to prevent the oil from rising to the rocks surface.

Natural Gas

Natural gas can also be heated to produce steam or combustion gases, but unlike the other two fossil fuels, natural gas undergoes a four-part process to separate various impurities, producing clean, dry natural gas for the consumer. Natural gas produces more methane than the other fossil fuels, but produces far less carbon dioxide and other harmful greenhouse gases.

Nuclear Power

Nuclear power is a bit more of an involved—and dangerous— process. Enter nuclear fission: Uranium is contained in a reactor core. Uranium atoms collide with neutrons in the core, splitting (fission) and striking each other in a chain reaction that releases heat, which is then used to produce steam.


Water reservoirs created by dams is forced through pipes against the turbine blades. A second hydroelectric method called run-of-river forces water against the turbine blades in order to turn the generator.


Heat is trapped underground, building energy that rises near the surface in the form of heat, that then turns the water into steam. The percentage of available geothermal resources is very low.

Solar Power

Solar cells made from silicon absorb the sun's radiation. Also called photovoltaic cells, photons from sunlight are either reflected, absorbed or passed through. The absorbed photons build up, and eventually electrons separate from the solar material's atoms. Certain electrons carrying a negative charge travel to the front of the solar cell, creating an imbalance similar to the negative and positive sides of a battery. Solar heating furnaces feature large-scale mirrors that create high temperatures in small spaces, and water-filled glass panels on your home can be used to heat water without having to waste electricity or natural gas.

Wind Power

A wind turbine converts the kinetic energy (object's motion) in wind into mechanical energy that is then used to generate electricity. The electricity is then fed through lines to a substation, and on to your homes and businesses. Wind Power is steadily becoming a widely-researched form of alternative energy, as several countries including the United States are building large-scale wind farms.


The combustion of waste creates steam. Landfill projects in the United States are attempting to trap and use methane from trash to form natural gas, which can then be converted to electricity. Waste-created steam can also generate electricity using steam turbines as mentioned before, and the heat created from burning waste and other materials such as wood, can produce fuels such as biodiesel as well.