From the article:

On Tuesday, Constellation Energy said it would partner with Google to add 890 megawatts of generating capacity at 11 existing nuclear plants across the PJM Interconnection, the country’s biggest and most capacity-constrained electricity market. The 20-year deal is similar to a smaller deal Constellation and Meta announced last year to add 30 MW at another one of its plants and a third agreement between Georgia Power and Google to add 96 MW at two nuclear power stations in the Peach State.

All three initiatives involve power uprates, wherein power plant owners upgrade turbines, steam generators, digital control systems, and other nonnuclear infrastructure to boost energy output faster and at a fraction of the cost of building a new reactor from the ground up.

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Constellation’s uprate announcement came one day after the DOE unveiled a $4.2 billion loan to extend the lives of three nuclear plants owned by Vistra, a Constellation competitor, in Pennsylvania and Ohio. The loan will also underwrite 433 MW of previously announced uprates at the plants, with Meta as the offtaker.

Those two deals represent the lion’s share of potential uprates in PJM and a significant chunk of the estimated 3 GW to 5 GW of uprate potential nationwide, Julien Dumoulin-Smith, a senior energy-sector analyst for the investment bank Jefferies, said in a client note Wednesday.

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Hyperscalers are also backing two of the three nuclear reactor restarts announced so far: Microsoft at the 835-MW Three Mile Island plant, which Constellation rechristened as the Crane Clean Energy Center; and Google at the 615-MW Duane Arnold Generating Station in Iowa. Both are set to power back up before the end of the decade.