Inside the US government project to create tiny nuclear reactors like batteries

Inside the US government project to create tiny nuclear reactors like batteries

Nuclear reactors have a well-deserved reputation for being massive construction projects that often result in cost overruns. Once they are finally built, their supervision and maintenance requires a team of dozens of trained experts.

But Yasir Arafat believes nuclear power doesn’t have to be like this.

Arafat is the engineering director of the microreactor project at one of the US government’s preeminent nuclear research laboratories, the Idaho National Lab, and in his role there, Arafat is leading efforts to build a tiny, relatively inexpensive nuclear reactor. It’s more of a nuclear battery, he says.

Arafat grew up in Bangladesh before going to college in the United States and is motivated by a deep sense of urgency to help the world decarbonize. The effects of global warming are not discussed in Bangladesh as a distant future scenario – climate change is already part of everyday life. Nuclear energy produces no greenhouse gas emissions, and Arafat hopes to help solve the problem by building a prototype microreactor that can help develop the industry.

The prototype will be called the MARVEL reactor, an acronym for the name of the Microreactor Applications Research Validation and Evaluation project, and the goal is to have the first operational by December 2023, making it the first advanced microreactor in the United States, Arafat told CNBC. (These photos show a prototype of the MARVEL reactor, powered by electrical heat rather than nuclear heat for preliminary research purposes.)

Yasir Arafat, the technical director of the Marvel microreactor project, shows the prototype to CNBC.

Photo courtesy of Magdalena Petrova, CNBC

The Idaho National Lab began designing and modeling the MARVEL reactor project in June 2020 under the direction of Arafat. Once completed, the MARVEL microreactor will be “the first of its kind that can show how we can truly scale down a nuclear system into something that is portable and transportable, and also capable of delivering heat and power to the end user.” Arafat told CNBC in a video interview in Idaho in May.

There are already a number of private companies — including Oklo, Westinghouse (where Arafat worked for a decade), and General Atomics — developing microreactors, and their goal is the same as the government’s: to develop a zero-emission, reliable source of energy.

A single microreactor could power a community of 1,000 to 10,000 people, whether it’s a hospital or a remote military base. The current power grid in the United States is based on a system where electricity is generated at a central location and distributed to end users. But microreactors are one component in a future vision for the power grid that is less centralized and more resilient to natural disasters.

Aside from being potential clean energy options for remote locations or small communities, microreactors could be an important part of a future clean energy grid that includes renewable solar and wind power and battery storage, Arafat said. Nuclear power is a baseload energy source, meaning it can provide power when the wind isn’t blowing and the sun isn’t shining, and can act as a back-up for the disruption to renewable energy.

A prototype for the Marvel reactor at the Idaho National Lab.

Photo courtesy of Magdalena Petrova, CNBC

Smaller = cheaper

Small modular nuclear reactors are orders of magnitude less complicated to design and build than conventional light water reactors. Microreactors go even further.

“All the hardware can be built in a factory like we make cars or automobiles,” Arafat told CNBC, allowing for the production of hundreds of microreactors a year. A microreactor can be transported from the factory to a customer site, fueled and started. The goal is to be able to deploy a microreactor in less than a week, “so it’s more of a nuclear battery than a big power plant,” he said.

“If we get really good at making these systems and use factory manufacturing, we can make them cheap enough for every campus across the country,” Arafat told CNBC.

Microreactors use a different type of fuel, enriched to just below the 20% limit set by nuclear non-proliferation requirements. This fuel, called HALEU, or High-Assay Low-Enriched Uranium, allows the reactor to be made smaller.

“We can actually build a much more efficient core that is significantly more compact and smaller. So we would actually need a much smaller amount of fuel to construct a reactor than a much larger core. That is the greatest benefit of higher enrichment,” said Arafat.

The small size and factory manufacture means that micronuclear reactors will be much cheaper to build than conventional light water reactors, which are chronically over schedule and under budget. The third and fourth reactors being built at the Vogtle plant in Georgia have become notorious examples of such overruns.

Yasir Arafat, the technical director of the Marvel Reactor microreactor project, speaking to CNBC at the Idaho National Lab.

Photo courtesy of Magdalena Petrova, CNBC

That’s not to say that the first microreactors off the assembly line will be as cheap or fast as the technology is going to be. But they will likely be deployed in places where cheap and reliable clean energy alternatives are not available, such as B. in remote communities in Alaska.

“Currently, diesel generators are the only technology that works there and they have to fly in the diesel fuel at those locations. They are so remote. If we can replace these diesel generators with a microreactor like this, it can certainly be significantly more economical than what they are paying for today,” Arafat told CNBC.

Because microreactors will be located near places where energy is used, transmission costs will be virtually nil, Arafat said.

Microreactors also require fewer staff and less maintenance than conventional reactors, in part because their fuel only needs to be replaced in five to 10 years, compared to less than two years for a light-water reactor, Arafat says.

Then there’s the security piece. The microreactor is designed in such a way that many of its systems work passively.

“Everything from heat generation, heat transport, heat removal to heat removal, all these coolant cycles are done passively without engineered systems,” Arafat told CNBC.

The side of the reactor is also made of boron carbide, the same material used in armored vehicles.

“So if artificial or extreme weather conditions can occur, there will be little or no impact on the actual operation or security of these systems,” Arafat said.

The prototype of the Marvel reactor at the Idaho National Lab.

Photo courtesy of Magdalena Petrova, CNBC

A critical piece of a larger puzzle, but not a panacea

While Steve Nesbit, president of the American Nuclear Society industrial trade group, supports the idea of ​​micronuclear reactors and the MARVEL project in particular, he cautions that they will not be a panacea for decarbonization.

That’s largely because a conventional light-water reactor produces hundreds of megawatts of power, and a microreactor produces between one and five megawatts of power, according to Arafat.

“I think they have a future, but there are limits to the ability to meet our clean energy needs with them,” Nesbit told CNBC. “Microreactors are ideal for remote microgrid situations, but not so much as a means of generating gigawatt-scale clean electricity for the conventional grid.”

The same view is shared by nuclear innovation expert and professor Alex Gilbert.

“They are distributed energy resources designed to power off-grid customers, small towns and industrial operations,” Gilbert told CNBC. “Alaska will likely be an early starter market, as will other parts of the Arctic like Canada, Russia and Scandinavia. They can play a key role in microgrids, complementing distributed solar power and batteries.”

But many of the key issues with developing microreactors are the same as with developing large-scale nuclear power plants in the US: “We have a stunted supply chain, the costs will be high and unpredictable, and the regulatory system is ill-equipped to deal with it.” said Gilbert.

However, addressing these issues for the deployment of microreactors can help pave the way for the same issues “for the large-scale deployment of larger advanced reactors,” Gilbert said.

Arafat knows the MARVEL project has a larger purpose: to flex the muscles of nuclear innovation in the US for the first time in decades. “So the art, science and technology of going through the development of new reactors is also a new realm for us in many ways,” Arafat told CNBC.

— CNBC’s Magdalena Petrova contributed to this report.