Tech industry turns to nuclear power for AI energy needs

The agreement with Constellation covers upgrades to the Calvert Cliffs Clean Energy Center on the western shore of Chesapeake Bay and constitutes Amazon’s first “uprate project” — an effort to increase the output of an existing nuclear plant. In return for the grid additions, Constellation will supply Amazon with up to 690 megawatts of power from across its fleet.

“It really helps secure the long-term future of Calvert,” David Dardis, Constellation’s senior executive vice president, said.

The 20-year agreement will support more than $3 billion in investments, including plant improvements and the increase in generating capacity, Constellation said. Amazon and Constellation also said they are exploring whether to install next-generation nuclear technology, including new reactors, at the site. Much of the industry’s recent focus has been on small modular reactors, or SMRs, which developers hope will be cheaper and faster to build than traditional large-scale plants.

Brandon Oyer, Amazon’s head of Americas power and water and a nuclear engineer, framed the deal as part of a broader portfolio of carbon-free energy investments. “Bringing net new capacity into that market makes sense—bringing net new carbon-free capacity makes even more sense,” Oyer said. He added that Amazon continues to contract for wind, solar and battery projects. “We’re still contracting for wind, we’re still contracting for solar, we’re still contracting for those combined with batteries. We’re continuing to go out and say, ‘Where else can we bring on new resources in a compressed timeline?’” he said.

Calvert Cliffs hosts two reactors that came online in the 1970s and can generate up to 1,790 megawatts of electricity, enough to power more than 1.3 million homes, according to Constellation. One reactor is up for re-licensing in 2034 and another in 2036, Dardis said, making the 20-year agreement significant for the plant’s continued operation.

Amazon’s Calvert Cliffs expansion comes after the company walked away last month from plans to build a data-center campus adjacent to the plant. Residents in the Maryland community voiced environmental, resource and health concerns about that project. Opposition to building data centers has grown nationally, particularly over fears the facilities could increase energy prices for nearby residents.

The shift toward nuclear reflects the steep electricity demands of artificial intelligence. Data centers built to train and run AI models can consume as much power as a midsize city, and nuclear energy is attractive to tech companies because it provides reliable, carbon-free electricity around the clock.

Amazon is already a major nuclear-power customer and investor. The company has a power purchase agreement with Talen Energy at the Susquehanna nuclear plant in Pennsylvania and is funding SMR development at the Cascade Advanced Energy Center in Washington state. Amazon also invested in X-energy, a reactor developer that went public earlier this year.

Other major technology companies have pursued similar arrangements. Microsoft agreed to a 20-year power deal to support Constellation’s restart of the undamaged reactor at Pennsylvania’s Three Mile Island, the site of the 1979 nuclear accident that turned public opinion against the industry for decades. Google is partnering with NextEra Energy to reopen the Duane Arnold Energy Center in Iowa by early 2029.

Nuclear energy has been gaining broader political and public support. Polling shows most Americans favor additional nuclear-power capacity, and President Trump has said he wants to quadruple nuclear-power generation over the next 25 years. The industry is also confronting the cost record of past builds: America’s last large nuclear-power project came in more than $16 billion over budget and seven years behind schedule, and only a handful of new commercial reactors have come online in the United States since 2000.

“I never would have thought this [was possible] a couple decades ago,” Oyer said.