Dive Brief:

• Exelon has formally notified the U.S. Nuclear Regulatory Commission of its intent to shutter the Three Mile Island nuclear facility in Pennsylvania, taking a major source of carbon-free generation off the grid.
• According to the Associated Press,  Exelon said in a letter to NRC that it plans to shutter the facility around Sept. 30, 2019 due to “severe economic challenges.”
• After failing to clear in the PJM capacity market auction, Exelon informed Pennsylvania lawmakers of plans to shut down if state lawmakers did not approve financial support for the 852 MW nuclear plant. 

Dive Insight:

Exelon is moving ahead with plans to shut down Three Mile Island, informing both the NRC and PJM that the plant will not be available next last year.  In addition to informing federal regulators if the decision, Exelon Generation Senior Vice President Bryan Hanson went into more detail with the regional grid operator.

The plant's Unit 1 "is unprofitable and has lost more than $300 million over the past five years despite being one of Exelon’s best-performing plants," Hanson wrote. "The energy market in PJM has not adapted to the evolution of the fleet, which has caused the devaluation of resources like Three Mile Island Unit 1."

The facility is "highly dependent on energy market prices that are at all time low levels as a result of a number of factors, including market rules that do not value the clean, resilient electricity provided by nuclear energy," he concluded.

Exelon wants Pennsylvania legislators to integrate nuclear energy into the state's renewable portfolio standard or pass a zero emissions credit (ZEC) program similar to those in New York and Illinois. The company used a similar strategy of threatening plant shutdowns to win approval for subsidies in those states. 

PennLive.com reports a bipartisan group of lawmakers are planning public hearings, but so far they have not expressed a policy preference.

Once the Three Mile Nuclear plant is shut down, it would not be possible to restart the facility and solid waste would be stored onsite.