By Avi Salzman

Shares of power producers Constellation Energy, Talen Energy, Vistra, and NRG Energy soared on Wednesday after the companies got more clarity on how soon they can start inking data-center deals.

Constellation was up 7.9%, its biggest increase in more than a year. Talen rose 9.5%, Vistra was up 6.9%, and NRG rose 8.3% on the day.

The three companies all have power plants that connect to a grid network known as PJM, which serves about 65 million customers in the Midwest and Mid-Atlantic. Their stocks have languished this year, because there aren't clear rules in PJM about how the companies can sell their power to tech companies, who want it for their data centers.

Late on Tuesday, PJM said in a letter that it will hold an auction this September allowing companies to sell power from new plants to data centers, moving the date up from September 2027. Evercore analyst Nicholas Amicucci wrote that the auction will be a "materially constructive" event for the companies. It is expected to clear some of the haze around how electricity companies can profit from data centers.

PJM is also working on new rules that will govern how data centers can connect to the grid more quickly. The whole process is politically fraught; states throughout the area have grown wary of data centers, which have contributed to rising electricity prices.

The new rules should be a welcome development for the power plant companies, leading to lucrative data-center agreements. While the companies had previously been able to sign such deals in PJM -- including Constellation's 2024 agreement to sell power from its Three Mile Island nuclear reactor in Pennsylvania to Microsoft -- those deals have slowed to a trickle in recent months amid regulatory uncertainty. All four power producers have seen their stocks fall by double-digits this year, with Constellation's down 23%.

Write to Avi Salzman at avi.salzman@barrons.com

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May 20, 2026 16:16 ET (20:16 GMT)

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