Companies owned by billionaires Bill Gates and Warren Buffett are planning to launch the first so-called Natrium nuclear reactor project. Many experts see the project as a misguided attempt to hit CO2 reduction targets.

Will smaller, modular reactors soon coexist with big ones like this here in Jenkinsville, South Carolina?

Bill Gates’ nuclear energy firm TerraPower and power company PacifiCorp — owned by Warren Buffett’s holding company Berkshire Hathaway — teamed up in September 2020 to launch the Natrium project. It’s about a small modular reactor they say will be commercially viable by 2030.

Many countries are weighing smaller, so-called modular, nuclear reactors as a way backing up low emission energy production during the transition from fossil fuel dependence to one based on renewable energy sources.

The reactor, to be built by Bechtel, will be in Wyoming, the United States top coal-producing state, Gates said. “We think Natrium will be a game-changer for the energy industry,” he said.

The US Clean Energy Transformation Act requires the elimination of coal by 2025 and full decarbonization of the grid by 2045. The US Department of Energy has awarded TerraPower $80 million (€70 million) to develop its ideas.

TerraPower says the plant will cost $1 billion, including engineering, procurement and construction costs, and is expected to take seven years to build. In the US, the cost of building a conventional nuclear power plant is around $25 billion and can take far longer to build.

“Smaller, advanced reactors like those being developed under the funding from Bill Gates and others offer novel applications, approaches, and opportunities for one of the world’s largest sources of noncarbon emitting energy, nuclear energy,” Brett Rampal, director of nuclear innovation at nonprofit Clean Air Task Force, told DW.

“They aren’t that small, this is 345 MW,” Antony Froggatt, a research fellow at Chatham House, told DW. “While much smaller than existing reactors (1,000 MW), they are still large and may not be as modular as intended and this undermines the argument that they can be built in factories and then shipped out, which is how they are supposed to be cheaper,” he warned. 

But “the next generation of advanced reactors will make more efficient use of materials, be easier to site, and offer a great balance to increased reliance on renewables in the form of always available clean energy,” Rampal insisted. “The Natrium concept also incorporates a thermal salt storage system which allows for the power plant to operate more flexibly and boost power output for portions of each day without having to make significant adjustments in the actual operation of the reactor,” Rampal said.

Flexibility matters

The Natrium reactors should supplement shortfalls in wind and solar power production as a backup generator. The project includes a 345 megawatt (MW) sodium-cooled fast reactor with molten salt-based energy storage to boost power output to 500 MW during peak power demand. Natrium technology has the ability to store heat in tanks of molten salt for future use, like a battery. 

“Natrium includes nitrate heat storage tanks— the same type of heat storage used in concentrated solar power systems. What that allows is economic variable electricity output — a replacement for gas turbines and the coal plants,” Charles Forsberg from the Massachusetts Institute of Technology Department of Nuclear Science and Engineering told DW. 

“The reactor operates at full power with variable electricity to the grid. Heat storage is about a factor of 10 less expensive than battery storage but needs a heat-producing technology to couple to heat storage. Nuclear is the low-carbon heat producing technology,” he said.


“Bill Gates has continually downplayed the role of proven, safe renewable energy technology in decarbonizing our economy, playing up instead more dangerous and risky technology like geoengineering and nuclear,” Michael E. Mann, professor of atmospheric science at Penn State University, told DW. 

Mann, a signatory to a recent declaration calling for decarbonization through 100% renewable energy, says he finds it troubling that Gates is trying to profit now from what he calls  “misdirection.” 

It’s misguided and dangerous, because it leads us down the wrong path. The obstacles to meaningful climate action aren’t technological at this point. They’re political,” Man argued.

Others agree. “Nuclear energy is a diversion from urgent climate action,” Jan Haverkamp of Greenpeace told DW. 

“The recent attention on nuclear energy is fully driven by the declining industry’s desperation for capital and its related lobby depicting it as a solution for climate change,” he added.

“New nuclear power, be it large reactors evolved from the existing fleet, or new small designs, can deliver only a marginal part of greenhouse gas emission reduction,” Haverkamp said, adding that a doubling of current capacity would yield less than 4% reduction compared with business as usual.

“It also does so too late and at a far too high cost. To make a dent in greenhouse gas emissions, we would need hundreds of new reactors, spreading the risk of proliferation,” he said.

“The Natrium reactor is what we call a fast breeder reactor type. These reactors are proliferation nightmares,” said Haverkamp. “They are delivered together with the reprocessing technology that also is necessary to isolate material for nuclear bombs. For that reason alone, I think the ideas of Gates in this respect are outright dangerous,” he went on.

“These are what we call PowerPoint reactors: They are in the design phase and before they are ready and tested and approved to go commercial, we will be well beyond 2030, for most of them rather around 2050. That means they have no role to play in urgent climate action,” he added.

Critics say production of these reactors would be a very capital-intensive enterprise. “So my short answer is: No, these reactors will most probably not play any significant role in climate action, if any,” Haverkamp said.

“Today, wind and solar energy are far cheaper, far faster to deploy, and far safer than traditional nuclear plants,” Robert Howarth, professor at Cornell University, told DW. 

“Might the plants envisioned by Gates and Buffet be better than traditional nuclear plants? Perhaps, but this is still just an experiment. And I doubt the claims being made. In any case, they are a distraction, and we are best off giving up on nuclear power and moving to 100% renewables as quickly as we can,” Howarth concluded.