Nuclear Power Plants

Nuclear reactors in the United States may have large concrete domes covering the reactors, which are required to contain accidental releases of radiation. Not all nuclear power plants have cooling towers. Some nuclear power plants use water from lakes, rivers, or the ocean for cooling.

Source: Stock photography (copyrighted)

Nuclear power comes from nuclear fission

Many power plants, including nuclear power plants, heat water to produce electricity. These power plants use steam from heated water to spin large turbines that generate electricity. Nuclear power plants use heat produced during nuclear fission to heat water.

In nuclear fission, atoms are split apart to form smaller atoms, releasing energy. Fission takes place inside the reactor of a nuclear power plant. At the center of the reactor is the core, which contains uranium fuel.

The uranium fuel is formed into ceramic pellets. Each ceramic pellet produces roughly the same amount of energy as 150 gallons of oil. These energy-rich pellets are stacked end-to-end in 12-foot metal fuel rods. A bundle of fuel rods, sometimes hundreds, is called a fuel assembly. A reactor core contains many fuel assemblies.

The heat produced during nuclear fission in the reactor core is used to boil water into steam, which turns the turbine blades. As the turbine blades turn, they drive generators that make electricity. Afterward, the steam is cooled back into water in a separate structure at the power plant called a cooling tower. The water can then be reused.

Nuclear power plants generate about 20% of U.S. electricity

The United States has 100 nuclear reactors at 60 operating nuclear power plants located in 30 states.¹ Thirty-six of the plants have 2 or more reactors, and 46 plants are located east of the Mississippi River. Nuclear power has supplied about one-fifth of annual U.S. electricity since 1990.

The United States generates more nuclear power than any other country

Of the 31 countries in the world that have commercial nuclear power plants, the United States has the most nuclear capacity and generation. France has the second-highest nuclear electricity generation and obtains about 75% of its total electricity from nuclear energy. Fifteen other countries generate more than 20% of their electricity from nuclear power.

Source: U.S. Energy Information Administration

Footnote

¹The newest U.S. reactor, Watts Bar Unit 2 in Tennessee, began initial operation in June 2016.