California was the largest net electricity importer of any state in 2019
Source: U.S. Energy Information Administration, State Electricity Profiles
Electricity routinely flows between the Lower 48 states and, to a lesser extent, between the United States and Canada and Mexico. Electricity generation exceeds electricity consumption in 25 states, and excess electricity is transmitted across state lines—almost 10% of U.S. electricity generation is traded among states. In 2019, California’s net electricity imports were the largest in the country at 70.8 million megawatthours (MWh), or 25% of the state’s total electricity supply. Pennsylvania’s electricity exports were the largest of any state in 2019, at 70.5 million MWh, or 24% of total supply.
California utilities partly own and import power from several power plants in Arizona and Utah. In addition, California’s electricity imports include hydroelectric power from the Pacific Northwest, largely across high-voltage transmission lines running from Oregon to the Los Angeles area.
Pennsylvania’s electricity generation was the third-largest in the nation, behind those of Texas and Florida. Natural gas-fired and nuclear power plants produced the majority of Pennsylvania’s in-state electricity in 2019, at 43% and 36%, respectively. Pennsylvania ranks second in the nation, after Illinois, in nuclear power generating capacity.