Compare stocks

FirstEnergy is an investor-owned holding company with operations across five mid-Atlantic and Midwestern states. FirstEnergy also owns and operates one of the nation's largest electric transmission systems.

Constellation Energy spun off from Exelon in 2022 and is now the largest US independent power producer. After acquiring Calpine in 2026, Constellation owns 55 gigawatts of power generation capacity. Constellation is the largest nuclear plant owner in the US with 22 GW of nuclear power generation capacity in six states. It also owns 4 GW of renewable energy projects. Constellation's retail energy business serves 2.5 million customers.