The remaining nuclear reactor at the Three Mile Island Generating Station (TMI) in Pennsylvania will shut down by the end of September.
The facility’s owner, Exelon, said Wednesday it was setting the closing date for Unit 1 at the financially struggling plant.
Exelon in 2017 said the plant, best known as the site of the worst nuclear incident in U.S. history in 1979, would be closed unless state lawmakers stepped in to provide financial relief to keep the 819-MW Unit 1 reactor online. Exelon then changed course, campaigning to save the plant and seeking a state subsidy to keep it operating, saying TMI should be compensated for producing carbon-free power.
Subsidies for nuclear power have been adopted in other states, including New York, New Jersey, Illinois, and Connecticut. In Pennsylvania, though, the state’s natural gas industry — Pennsylvania sits in the heart of the Marcellus Shale — waged a strong lobbying effort against help for the nuclear industry. That effort was helped by opposition to subsidies from consumer advocates and industrial gas users.
“With only three legislative session days remaining in May and no action taken to advance House Bill 11 or Senate Bill 510, it is clear a state policy solution will not be enacted before June 1,” Exelon said in a press release Wednesday that referenced the proposed nuclear subsidy bills.
Exelon had said it needed to decide TMI’s fate by June 1, since it would need to purchase fuel for the plant for its next operating cycle.
“Today is a difficult day for our employees, who were hopeful that state policymakers would support valuing carbon-free nuclear energy the same way they value other forms of clean energy in time to save TMI from a premature closure,” said Bryan Hanson, Exelon senior vice president and chief nuclear officer.
Three Mile Island’s Unit 1 is licensed to operate through 2034, and shutting it down will cut its life short by 15 years. Power from the plant along the Susquehanna River is expected to be replaced by electricity from coal and natural gas-fired power plants that run below capacity in a saturated market.
The plant near Harrisburg employs about 700 workers.
Decommissioning Unit 1, dismantling its buildings and removing spent fuel could take six decades and cost more than $1 billion, Exelon said.
The destroyed Unit 2 is sealed and its twin cooling towers remain standing. Its core was shipped years ago to the U.S. Department of Energy’s Idaho National Laboratory. What is left inside the containment building remains highly radioactive and encased in concrete.
Work to dismantle Unit 2 is scheduled to begin in 2041 and be completed in 2053, its owner, FirstEnergy, said.