Constellation Energy (NASDAQ:CEG) will continue to pursue deals to develop data centers on the sites of its U.S. power plants, even after the Federal Energy Regulatory Commission ruled against "co-located" arrangements, company executives said Monday, according to Reuters.

Constellation (CEG) will seek guidance from regulators after FERC's decision "while simultaneously pursuing commercial strategies for co-location that are permitted under our existing rules," CEO Joseph Dominguez said on the company's earnings conference call.

FERC rejected an amended interconnection service agreement that would have facilitated expanded power sales to a co-located Amazon data center from a nuclear power plant in Pennsylvania that is majority owned by Talen Energy (TLN).

Constellation (CEG), the largest operator of U.S. nuclear power plants, had backed Talen (TLN) on the issue, and its shares have surged this year partly on the prospect of developing co-located data centers.

The regulatory challenge was brought by electric utilities Exelon (EXC) and American Electric Power (AEP), which opposed the Talen-Amazon data center amended ICA, saying it threatened to raise power bills for customers and hurt grid reliability.

Constellation (CEG) shares continue as the day's biggest S&P 500 loser, -11.5%; Talen (TLN) -1.9%, Exelon (EXC) -0.5%, AEP (AEP) +0.8%.