Nuclear Power
Three Mile Island Unit Eyes $1.6B Revamp, Restart in Microsoft Deal
Closed Palisades nuclear plant in Michigan also finalized on Sept. 30 a $1.5B federal loan guarantee for its restart upgrade, the US Energy Dept. said..
Constellation Energy Corp. aims to restart its two-reactor Three Mile Island Unit 1 in Pennsylvania, seen here operating in foreground before its shutdown in 2019, in deal to solely supply tech giant Microsoft. The site's Unit 2 in background was closed after a 1979 near meltdown.
Image courtesy of US Energy Dept.
Constellation Energy Corp. announced a 20-year deal with Microsoft to supply regional data centers with power from what is described as a $1.6-billion revamp and restart of the Three Mile Island nuclear plant Unit 1 reactor near Harrisburg, Pa., which was shuttered in 2019 “for economic reasons,” after 20 years of operation, said firm CEO Joe Dominguez.
The unit is adjacent to but not connected with the plant’s Unit 2, which closed in 1979 after a near meltdown and is being decommissioned by its new owner, Energy Solutions. A restart of Unit 1, renamed the Crane Clean Energy Center, was announced Sept. 20. The unit closed in 2019 and is set to restart in 2028, but owner Constellation Energy did not disclose design and construction firm selections for plant upgrades to enable it to add 835 MW of energy to the area grid operated by PJM Interconnection over 20 years to match power used by tech giant's data centers.
Constellation, which told media it had not yet applied to the U.S. Nuclear Regulatory Commission for restart permission, said it also will seek license renewal to extend plant operations to at least 2054.
Also seeking commission OK to restart, as early as late 2025, is the 800-MW Palisades nuclear reactor in Michigan, owned by operator Holtec since 2022 after its retirement that year by former owner Entergy. The US Energy Dept. announced Sept. 30 it finalized a $1.52-biilion federal loan guarantee for the project upgrade that was conditionally awarded in March. The plant had operated since 1971.
If both restart applications gain federal approvals, they would be the first such reactivations of closed U.S. nuclear plants.
“These renewals extend the life of reactors to 80 years and require substantial maintenance investment, about $1 billion per reactor,” DOE said. The agency also will provide $1.3 billion in funding to two Michigan area power cooperatives to boost nuclear energy purchases from the Palisades plant.
But signs of stress corrosion cracking on 1,163 plant steam generator tubes in the Palisades plant “far exceeded estimates based on previous operating history,” says a just-released federal document cited by Reuters in an Oct. 3 report. The result was “not entirely unpredicted,” a Holtec spokesperson told the news service, since procedures to maintain Palisades were not followed when the plant closed.
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Michigan Gov. Gretchen Whitmer (D) said she favors plant restart “to secure [state] competitiveness for future economic development,” but Edwin Lyman, the Union of Concerned Scientists' nuclear power safety director, said “It’s just not clear it’s going to be worth the expense.”
Palisades nuclear plant in Michigan, which was retired in 2022 and now is owned by Holtec International, has finalized terms for a $1.52-billion federal loan guarantee to restart operations, the US Energy Dept. said Sept. 30.
Image courtesy of Holtec International
'Significant Investment'
The revamped Three Mile Island unit, set to operate in 2028, will require “significant investments” in Unit 2 plant systems, including the turbine, generator, main power transformer and cooling and control systems, said Constellation.
The owner did not disclose financial details of the Microsoft deal, but Pennsylvania Gov. Josh Shapiro (D) supports the restart.
But there is new controversy stemming from details reported first by The Washington Post on Oct. 3 related to Constellation's application several months ago for a $1.6-billion federal loan guarantee that was not previously disclosed. “To the extent we may seek a loan, [the company] will guarantee full repayment,” Constellation said in a statement. "Any notion that taxpayers are taking on risk here is fanciful given that any loan will be backstopped by Constellation's entire $80-billion-plus value."
The owner is also expected to seek federal clean energy tax credits under the 2022 Inflation Reduction Act to offset restart costs, according to The Post, which said that Energy Secretary Jennifer Granholm had previously estimated the incentives could cut those expenses by up to half.
Constellation touted a regional building trades-sponsored study that said the restart would create 3,400 direct and indirect jobs and generate regional economic benefits, adding that it has committed $1 million over the next five years to support regional workforce development and other community investment.
DOE also announced Sept. 30 new funding totaling about $100 million under a program to create nuclear plant safety training and workforce development related to "long-term maintenance and sustainability of [current] reactors," which it said is "is crucial to keeping pace with the growing demand for clean energy."
In its first announced round, DOE said it would provide up to $50 million for nuclear safety curriculum development and training through university-led partnerships with industry, national laboratories and colleges, with applications due on Jan. 14 and awards to be announced next spring.
