So long, Three Mile Island. The Pennsylvania plant's remaining nuclear reactor shut down at noon Friday—and not because of anti-nuclear activism, the Hill reports. The plant best known for its partial meltdown in 1979 has fallen prey to the economics of modern energy consumption. It's licensed to continue until 2034, but owner Exelon Generation called it quits after Pennsylvania said it wouldn't let nuclear plants charge extra because they're emissions-free, mostly stable power sources. The plant's cleanup is expected to take decades and cost roughly $1.2 billion, per CNN. As for the 675 employees, Exelon says it's trying to place them in other company positions.
The move comes as changing economics—like more affordable renewable energy and cheap natural gas—are making it hard for nuclear plants to survive, per USA Today. Five plants and six reactors have shut down since 2013 and others are destined for closure unless they get more financial support, according to the Union of Concerned Scientists. The Three Mile Island accident played an important role in undermining US confidence in nuclear power, but the debate continues. "Right now, nuclear is more than 50% of our non-carbon causing energy," says Sen. Cory Booker, D-NJ. "So people who think we can get there without nuclear being part of the blend just aren't looking at the facts." (Read more nuclear power stories.)