How TerraPower Is Building the Nuclear Reactor That Could Power the AI Economy — and Why the Entire World Is Watching

Bill Gates has been thinking about nuclear energy since the early 2000s. In Kemmerer, Wyoming, in 2026, that thinking is becoming concrete — literally. What TerraPower is building at the Natrium plant is not just a power facility; it represents a blueprint for the next century of clean baseload energy.

The Problem That Founded a Company

In 2006, Bill Gates sat down with a group of nuclear engineers and asked them a question that has defined the two decades of work that followed: what would nuclear power look like if you started from scratch today, using everything we now know about materials science, digital control systems, and energy storage, unconstrained by the design decisions that were made in the 1950s?

The answer that emerged from those conversations became TerraPower — a nuclear innovation company founded in Bellevue, Washington, with the mission of developing advanced nuclear technologies that could provide reliable, affordable, zero-carbon electricity at the scale required to genuinely decarbonize the global energy system.

The founding insight was that the nuclear industry's problems were not primarily regulatory or political — though both had played a role in its stagnation. They were architectural. The light water reactors that formed the basis of the global nuclear fleet were designed in an era when the primary engineering constraint was safety in the face of limited computational power and immature materials science. The solutions those constraints produced were reliable — but they were also expensive, slow to build, and dependent on continuous active cooling systems that, as the Fukushima disaster demonstrated in 2011, could fail under sufficiently adverse conditions.

TerraPower's Natrium reactor is built on a fundamentally different set of assumptions. It uses liquid sodium as a coolant instead of water — a choice that eliminates the pressurisation required in water-cooled reactors, simplifying the plant design significantly and reducing the capital cost of containment structures. It incorporates a molten salt energy storage system that allows the plant to bank heat when electricity prices are low and release it as generation when demand is high — giving a nuclear plant the kind of dispatch flexibility that has historically been the exclusive domain of gas turbines and batteries. And it is designed from the ground up for factory manufacturing, with the goal of compressing construction timelines and driving down the per-kilowatt capital cost through serial production.

The Strategic Context: Why AI Made Nuclear Urgent

For most of TerraPower's first fifteen years, the case for advanced nuclear was primarily a climate case. The decarbonisation imperative — the need to replace fossil fuel generation with zero-carbon alternatives at scale — was the primary commercial argument, and it was a slow-moving one, constrained by policy timelines, carbon pricing uncertainty, and the dramatic cost reductions in solar and wind that made the economics of any new baseload investment difficult to justify.

The AI infrastructure buildout of 2024 and 2025 changed that calculus with extraordinary speed.

Microsoft signed an approximately $16 billion, 20-year power purchase agreement for the entire 835 MW output of the Three Mile Island Unit 1 restart. Meta announced deals for up to 6.6 GW of nuclear capacity through TerraPower, Oklo, and utility PPAs. Google signed the first US corporate SMR fleet deal with Kairos Power for 500 MW. NVentures, NVIDIA's investment arm, also invested in TerraPower.

The common thread across all of these commitments is the recognition that AI data centres require power that is available 24 hours a day, 365 days a year — and that the combination of solar, wind, and battery storage that works well for many commercial and industrial electricity consumers does not work for hyperscale compute. The compute cannot pause when the sun is not shining or the wind is not blowing. The latency requirements of AI inference are incompatible with the kind of demand response that allows other large consumers to shift load when grid conditions are tight.

Nuclear — dispatchable, zero-carbon, scalable — is the only proven technology that meets all of those requirements simultaneously. And the Natrium reactor's integrated storage system makes it even better suited to the data centre use case than conventional nuclear, because it can modulate its output to match the data centre's demand profile rather than operating at fixed capacity.

The Kemmerer Plant: What Is Actually Being Built

The Natrium demonstration plant in Kemmerer, Wyoming — on the site of a retiring coal plant — is the most consequential energy infrastructure project in North America, and one of the most significant in the world. It is the first advanced nuclear reactor to begin construction in the United States in decades, and the first sodium-cooled fast reactor to be built anywhere in the Western world.

The project received a construction permit from the Nuclear Regulatory Commission in December 2025, following a safety evaluation process that was itself a demonstration that the NRC's regulatory framework could accommodate advanced reactor designs within timeframes that commercial developers could plan around.

TerraPower's Natrium reactor is liquid-sodium cooled and, when coupled with a molten salt energy storage system, is capable of supplying up to 500 MWe for several hours. The NRC finished its environmental review and issued the final safety evaluation; a decision on the construction permit came in the first half of 2026. The facility is targeted for commercial operation in the early 2030s.

The Workforce and Community Dimension

One of the most deliberate and carefully executed aspects of TerraPower's Kemmerer strategy is its engagement with the community that will host the plant — and with the workforce that will build and operate it. Kemmerer is a coal community. The Naughton coal plant that the Natrium facility is replacing employed hundreds of people directly.

TerraPower has made the employment transition a central element of the project's value proposition. The Natrium plant will employ more people than the coal plant it replaces — in higher-skilled, higher-wage roles — and the construction phase is employing local workers and contractors. The company has invested in workforce training programmes that allow existing coal plant workers to transition to nuclear operations roles, preserving institutional knowledge.

The Investment Landscape & Global Race

X-energy filed a draft S-1 with the SEC in March 2026 for a Nasdaq IPO targeting $300 million, backed by $1.4 billion-plus in total funding including Amazon's $700 million strategic investment. Key publicly traded SMR and nuclear stocks include Oklo at approximately $12.9 billion market cap, NuScale Power at approximately $5.3 billion, Nano Nuclear Energy at approximately $1.2 billion, and Centrus Energy at approximately $3 billion. Holtec International confidentially filed for an IPO in February 2026 targeting a $10 billion-plus valuation.

China's Linglong One, a 125 MWe SMR, is expected to begin commercial operation in the first half of 2026, making it the world's first land-based commercial SMR. In Canada, Ontario Power Generation broke ground on a BWRX-300 at Darlington in May 2025.

The Lesson for Every Energy-Intensive Organisation

The TerraPower story carries lessons that extend well beyond the nuclear sector. For every organisation operating at the intersection of energy intensity and sustainability commitment, the Kemmerer project is a demonstration of what serious long-term energy strategy looks like.

The concrete is being poured. The world is watching.