Ask anyone in Texas who’s opened an electric bill after a heat wave: the priciest power of the year isn’t the power that runs all day, it’s the power that only turns on for a few brutal hours when everyone cranks the AC at once. A reactor going up in Wyoming is being built specifically to fight that price spike.
What Doosan Just Signed Up to Build
On August 21, South Korea’s Doosan Enerbility signed a contract to manufacture core reactor components for TerraPower’s Natrium reactor, going up in Kemmerer, Wyoming. The deal covers the core barrel, the guard vessel, and the internal supports that hold the reactor’s core in place, according to World Nuclear News.
This isn’t a routine supplier announcement. Doosan already forges heavy reactor components for plants around the world, so it isn’t learning on the job. It’s applying manufacturing muscle it has already proven elsewhere to a brand-new reactor design, and that cuts real risk out of the build.
Why Natrium Acts Like a Battery, Not Just a Reactor
The TerraPower Natrium reactor pairs a 345-megawatt sodium-cooled fast reactor with a molten salt energy storage system. That storage tank can push output up to 500 megawatts whenever the grid needs a burst of power. A conventional nuclear plant runs at one fixed output around the clock. Natrium banks heat when demand is low and releases it fast when demand spikes, behaving almost like a battery bolted onto a reactor.
That matters on the exact days your bill gets ugly. Grid operators usually cover demand spikes with peaker plants, gas-fired units that only run a handful of hours a year and charge accordingly, since their whole business model is showing up for the worst moments. In Texas, ERCOT’s own market rules let wholesale power spike into the thousands of dollars per megawatt-hour during a scarcity event, more than a hundred times an ordinary day’s rate of $30 to $40. A reactor that can burst to 500 megawatts on its own competes directly with that expensive peaking power, and every megawatt it displaces is a megawatt that didn’t get priced at those peaker rates.
Sodium coolant also runs at far lower pressure than the water inside a traditional reactor, which simplifies the containment structure and removes some of the failure modes that keep regulators cautious about new designs.
A Concrete Step, Not a Press Release
Component contracts like this one separate real projects from paper reactors. Doosan says years of joint engineering work with TerraPower have pushed its designs to “manufacturing-ready” status, meaning the blueprints are buildable specs now, not concepts. Non-nuclear construction at Kemmerer started back in 2024, and the project still targets commercial operation by 2030.
Feeding this reactor will also take a steady supply of HALEU, the enriched fuel that’s still catching up with demand from projects like this one. We’ve tracked that squeeze in our look at the state of nuclear fuel supply in 2026, and enrichment capacity is expanding to help close the gap, including through Urenco’s newly expanded US enrichment plant.
What to Watch Next
Kemmerer is on track to be the first utility-scale advanced reactor built in the United States. Every manufacturing contract that lands moves that milestone from a plan on paper toward steel in the ground. If Natrium succeeds, it proves a sodium-cooled fast reactor can run safely at commercial scale, and that a reactor with built-in energy storage can take the edge off the grid’s worst, most expensive hours.