Talen Energy is trying to figure out why a reactor at its Susquehanna nuclear power plant automatically shut down.
The Allentown-based company issued a news release saying the unit shut down just before 3:30 p.m. Thursday at the plant a few miles north of Berwick, in Luzerne County.
The (Allentown) Morning Call reports the company saying there was no risk to the public, and that nobody was hurt and no plant equipment was damaged.
Once the company figures out why the reactor shut down, they'll take steps to restart it.
The plant's second reactor is operating normally at full power.
The reactors have a combined output of about 2600 megawatts. Each reactor generates enough power for about 1 million homes.