How Does the Power Grid Work?

Ever since Thomas Edison and Nikola Tesla battled it out during the War of the Currents in the late 19th century, electricity has been a central part of life in America.

We are constantly connected to the power grid, which keeps our food refrigerated, our homes heated, our computers running and our rooms lit. Power lines, transmission stations and power plants have become a part of the landscape — to the point that we hardly notice them.

But have you ever really thought about the complex system that generates electricity, carries it across miles of transmission lines and then delivers it to your home?

Power Grid Infographic

As you can see in the infographic above, our power grid is a network of power plants, substations, transformers, wires, sensors and poles that carry electricity sometimes hundreds of miles to be distributed to our homes, schools and offices.

Parts of this network are more than a century old — 70 percent of the grid’s transmission lines and power transformers are over 25 years old, and the average age of power plants is over 30 years old. Today, our electricity needs are more sophisticated and the strain on the grid is higher than ever.

That’s why the Department of Energy’s experts are working to strengthen and update the grid with new technologies that help prevent outages, provide for cybersecurity and enable real-time data sharing, among other innovations.

(Graphic by Sarah Gerrity, Energy Department.)