The tech industry is increasingly hungry for small modular nuclear reactors to power large server farms. But the technology is still in early stages, and data centers need steady electricity faster than any nuclear developers can license, permit and build SMRs. In the meantime, the companies developing artificial intelligence are relying on fossil gas, spending billions to build out infrastructure that critics warn will lock in long-term use of a fuel with volatile prices and planet-heating pollution.
To Simon Irish, the chief executive of the reactor startup Terrestrial Energy, this choice — between waiting for new nuclear, and relying on gas today — is a false one.
On Tuesday, his North Carolina-based company plans to announce a deal with the energy services giant Ameresco to explore powering data centers, industrial plants and off-grid government facilities with gas in the short term, with the option to swap out the fossil fuel for Terrestrial’s molten salt reactors, Latitude Media has learned.
“We can customize, integrate, hybridize. Moving those systems around in a clever way is the best way to deliver high value, cost-competitive energy supply quickly to our customers,” Irish said in an exclusive interview. “I think that’s the real game in town.”
Ameresco said it’s considering “half a dozen” projects with the federal government and commercial buyers that could benefit from nuclear reactors down the road. Earlier this month, the company hired its first director of nuclear partnerships to oversee future atomic energy projects.
Traditional light water reactors integrate the steam-supply system with the nuclear safety equipment, making it impossible to swap out the sources of heat used in the process. But Terrestrial’s design relies instead on a pair of reactors that transfer heat from the molten salt to the steam generators, keeping the equipment separate. Since molten salt can safely reach higher temperatures than water, which is the coolant used in most nuclear reactors, Terrestrial’s system is able to generate more heat at a much lower pressure.
Unlike other developers betting on molten salt reactors, such as the Bill Gates-backed TerraPower, Terrestrial’s model runs on traditional low-enriched uranium, avoiding more expensive, rare fuels.
“We recognize the potential for a gas-fired bridge to nuclear, and Terrestrial Energy’s design accounts for that,” said Greg Caplan, the vice president of federal business development at Ameresco. “The age of energy abundance is around the corner and Ameresco as a systems operator wants to be part of that.”
The partnership is at an early stage. The memorandum of understanding kicks off a due diligence process to “assess the viability of that gas-fired bridge to the Terrestrial SMR,” Caplan said. The deal did not include any mutual investments.
But the agreement could nonetheless give Terrestrial a boost in the increasingly crowded SMR sector, especially as major tech companies embrace their startups of choice.
Last October, Google backed the SMR developer Kairos, promising to buy 500 megawatts of power for its data centers. Days later, Amazon bought a stake in the SMR developer X-energy.
The federally-owned Tennessee Valley Authority, meanwhile, is angling to build the first U.S. versions of GE-Hitachi Nuclear Energy 300-MW SMR in the coming years. And in March, the Trump administration got involved as well, by reopening a $900 million fund to buy power from SMRs.
“The federal government’s beginning to play quite an active role, and obviously Ameresco is very experienced in business partnerships that deliver solutions to the federal government,” Irish said. “That’s a very important additional capability that Ameresco brings to the table.”
