The electricity system

About the U.S. Electricity System

Today’s U.S. electricity system is a complex network of power plants, transmission and distribution wires, and end-users of electricity. Today, most Americans receive their electricity from centralized power plants that use a wide variety of energy resources to produce electricity, such as coal, natural gas, nuclear energy, or renewable resources such as water, wind, or solar energy. This complex system of generation, delivery, and end-users is often referred to as the electric power grid.

Use the diagram below to learn more about the electric power grid. Click each component to get an overview with links to more detailed information.

How and where electricity is generated

Electricity in the United States is generated using a variety of resources. The three most common are coal, natural gas, and nuclear power. Some of the fastest growing sources are renewable resources such as wind and solar. Most U.S. electricity is generated at centralized power plants. A much smaller but growing amount of electricity is produced through distributed generation—a variety of technologies that generate electricity at or near where it will be used, such as onsite solar panels and combined heat and power. Learn more about centralized and distributed generation.

Electricity delivery and use

Once electricity is generated at a centralized power plant, it travels through a series of interconnected, high-voltage transmission lines. Substations “step down” high-voltage power to a lower voltage, sending the lower voltage electricity to customers through a network of distribution lines. 
Residential, commercial, and industrial customers each account for roughly one-third of the nation’s electricity use. The transportation sector accounts for a small fraction of electricity use.