Google today announced that it has signed a deal with nuclear power startup Kairos Power to build seven small nuclear reactors to power its data centers. The agreement commits to add about 500 megawatts of carbon-free power at a time when energy demand for data centers and AI is surging.
According to Google, the new power plant is scheduled to be operational by the end of 2010. It’s unclear whether the reactor will be connected directly to Google’s site – an arrangement known as “behind the meter” – or whether it will feed the grid, with Google claiming carbon-free power through its agreement with Kairos.
The deal sees Google join Microsoft and Amazon in turning to nuclear power to satisfy its thirst for power. Last September, Microsoft announced it would pay Constellation Energy to restart the nuclear reactor at Three Mile Island, which was shut down in 2019. Earlier this year, Amazon said it would build a hyperscale data center and connect it directly to another nuclear power plant in Pennsylvania.
If Kairos can meet the 2030 deadline, recent forecasts will likely be revised slightly. As recently as July, the company was targeting commercial operation by the “early 2030s,” according to an article published by the U.S. Department of Energy. Even if Kairos achieves its revised goals, it will be locked in competition with fusion startups that aim to have commercial-scale power plants operational before 2035.
Kairos is one of a new breed of nuclear startups building so-called small modular reactors (SMRs) to lower the cost and speed up construction of nuclear power plants.
Most nuclear power plants are large facilities, delivering more than 1,000 megawatts of power, but they take years to plan and nearly a decade to build. America’s newest nuclear fission reactors, Vogtle Units 3 and 4 in Georgia, came online in 2023 and 2024, respectively, breaking a seven-year drought (the next newest reactor came online in 2016). Still, they were seven years late and $17 billion over budget.
SMR startups are attempting to build nuclear power plants faster and cheaper, using mass production techniques to lower costs and speed up construction. Kairos is trying to take the technology one step further by cooling the reactor with molten salts of lithium fluoride and beryllium fluoride rather than water. The Nuclear Regulatory Commission has approved the startup’s plan for a 35-megawatt demonstration reactor, something that Oklo, another SMR startup, had avoided.
Despite regulatory approval, Kairos still faces serious challenges. Because commercial small modular reactors are not yet operational, their economic feasibility is largely unproven. Moreover, Kairos’ molten salt design goes beyond decades of industry experience with water-cooled reactors.
But Kairos’ biggest challenge may not be technical at all. According to Pew Research, 56% of Americans say they favor nuclear power, while 44% still oppose it. Once a site for a nuclear reactor is selected, the number of opponents may increase. The Pew survey only asked people whether the United States should use nuclear power expansion in general and not in its backyard. Moreover, while support for nuclear energy is near recent highs, far more people support wind and solar. Both of these technologies are available today and cost much less than new nuclear power plants.
