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TerraPower’s Data-Center Pitch Is a Heat Battery Attached to a Nuclear Reactor

The project is expected to break ground in 2027, but its customer is not public. The central question is whether stored reactor heat can respond to volatile computing demand without forcing the reactor itself to slow down.

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TerraPower’s Data-Center Pitch Is a Heat Battery Attached to a Nuclear Reactor

Story brief

3 key points

TerraPower is positioning Natrium’s thermal-storage system as a way to power fluctuating AI data-center loads without ramping the reactor itself. The 345-MW design stores excess heat in molten sodium and can release it for extra turbine generation when demand rises. A customer has not been disclosed, and construction is only expected to start in 2027, so the proposal remains unvalidated in a live data-center...

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    Natrium keeps the reactor steady while stored heat changes turbine output, adapting a renewable-grid feature to volatile data-center demand.

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    Cited ramp rates are about 5% of capacity per minute for existing reactors and 10% for newer SMRs—not measured Natrium performance.

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    TerraPower’s Wyoming plant is under construction; the proposed data-center facility would be its second plant.

TerraPower is reportedly planning its first data-center power project, expected to break ground in 2027. Its pitch is more specific than always-on nuclear electricity: the Natrium design stores heat when electricity demand is lower, then uses that reserve to increase generation when demand rises. The customer has not been identified publicly.

That design addresses a difficult match between nuclear plants and AI data centers. Nuclear reactors operate best at high, steady output, while data-center electricity use can move sharply as graphics processors handle training jobs and user requests. TechCrunch cited National Laboratory of the Rockies figures showing that existing reactors can change output by about 5% of rated capacity per minute; newer small modular reactor designs can reach roughly 10%.

Bloomberg, as cited by TechCrunch, reported that TerraPower plans to announce the project. The reported 2027 construction target makes it a future deployment rather than a working data-center power plant. The disclosed design and the missing customer name leave the scale and arrangement of the proposed deployment unclear.

The reactor supplies steady heat; the reservoir handles the swing

Natrium is a 345-megawatt, molten salt-cooled reactor with a large reservoir of molten sodium. Rather than repeatedly changing the reactor’s output, TerraPower’s design sends excess heat into the sodium. When demand spikes, that stored heat can generate additional steam for turbines and raise electricity production.

TerraPower developed the approach to complement intermittent wind and solar generation. The same storage buffer can be applied to a different problem: uneven demand from a data center rather than uneven supply from renewables. It is a way to make the turbine side of a nuclear plant more responsive while the reactor continues operating steadily.

Why storage changes the data-center proposition

For a data-center operator, the attraction is not merely a dedicated source of electricity. It is the prospect of meeting changes in load without asking a reactor to follow every fluctuation. TechCrunch said rapidly changing data-center loads can require large battery banks to smooth the swings, adding cost. Thermal storage is TerraPower’s proposed alternative buffer, using heat already produced by the reactor.

TerraPower’s deployment record

  • Its first power plant is already under construction in Wyoming.
  • The reported data-center project would be the company’s second power plant and is expected to break ground in 2027.
  • TerraPower announced in January that Meta had agreed to buy eight Natrium power plants.

The test still lies ahead

The data-center plan gives TerraPower a potential use for a feature designed for a renewable-heavy grid. But the key evidence will come with deployment: whether the molten-sodium reservoir can supply the promised flexibility for a data-center load while the reactor remains at steady operation. For now, the project’s scheduled construction date and unnamed customer mark the boundary between the design’s rationale and demonstrated use.

Sources

  1. techcrunch.comTerraPower’s nuclear reactor has a secret weapon for powering AI data centers | TechCrunch