The plant was shut down, then, because of cheaper generation sources available. Now, they will restart the plant in a contract with Microsoft, to provide carbon free electricity for future AI data centers: Constellation Energy to restart Three Mile Island and sell the power to Microsoft (cnbc.com)
Story says it is estimated that 8% of U.S. electrical capacity will go to data centers by 2030. Also says EV charging will likely increase demand on generation too. As well as conversion of natural gas appliances to electric.