Tech companies want nuclear power. Some utilities are throwing up roadblocks

Tech companies are increasingly looking to directly connect data centers to nuclear plants as they race to secure clean energy to power artificial intelligence, sparking resistance from some utilities over the potential impact on the electric grid.

Data centers, the computer warehouses that run the Internet, in some cases now require a gigawatt or more of power, comparable to the average capacity of a nuclear reactor in the U.S.

The data centers are essential to U.S. economic competitiveness and national security as the country competes with adversaries such as China for supremacy in the race to develop AI, said Joe Dominguez, the CEO of Constellation Energy, which operates the largest nuclear fleet in the U.S.

"When you're talking about large [demand] load that also wants to use zero-emission energy, you're going to bring it very close to nuclear power plants," Dominguez said on Constellation's second-quarter earnings call Tuesday. Constellation, headquartered in Baltimore, operates 21 of the 93 reactors in the U.S.

Constellation's shares have surged 58% this year, the sixth-best stock in the S&P 500, as investors attach a higher value to the company's nuclear power capacity to meet the growth in data centers. Shares of Vistra Corp., based outside Dallas and owner of six reactors, have doubled this year, the second-best performing stock in the S&P after AI chipmaker Nvidia.

Tech companies are building out data centers just as power supply is increasingly constrained due to the retirement of coal plants and as demand is climbing from the expansion of domestic manufacturing and the electrification of vehicles.

The largest grid operator in the U.S., PJM Interconnection, warned in late July that power supply and demand is