The future of clean energy lies in microreactors

Companies are betting on nuclear energy as a clean energy solution, with the potential to power data centers, oil platforms and remote communities

Nuclear power companies are trying to reduce the size of reactors to the equivalent of shipping containers in a bid to compete with electric batteries as a zero-carbon energy source.

Led by Westinghouse, the race to develop “microreactors” is based on the idea that they can replace diesel and gas generators used by data centers, isolated off-grid communities and offshore oil and gas platforms.

“Initially, the idea was to serve parts of the economy that are difficult to decarbonize, especially remote communities that rely on transportable diesel, which is very expensive,” said Jon Ball, head of Westinghouse’s eVinci microreactor program. “But interest has grown a lot, and we believe this will be a significant growth area.”

The nuclear industry is experiencing a renaissance as governments and big technology companies seek clean sources of energy to meet their climate commitments. Dozens of projects are underway to develop small modular reactors with capacities of up to 300 megawatts.

Microreactors have a much smaller capacity, up to 20MW, enough to power around 20,000 homes. They will likely operate as large batteries, with no control room or workers on site. The reactors would be transported to the site, connected, and left running for several years before being returned to the manufacturer for refueling.

In December, Westinghouse won approval from US nuclear regulators for a control system that will eventually allow the 8MW eVinci to be operated remotely. The reactor, which has few moving parts, uses tubes filled with liquid sodium to transfer heat from its nuclear fuel to the surrounding air, which can drive a turbine to generate electricity or be directed to heating systems.

“Our goal is to operate autonomously from a central hub that monitors a fleet of reactors deployed globally,” Ball said.

The reactor uses small amounts of ceramic-coated Triso fuel, designed to withstand extreme temperatures without melting.

The eVinci is the first microreactor to complete engineering studies for a testing program — scheduled to begin in 2027 — at the Idaho National Laboratory, in the USA. Recently, Westinghouse signed an agreement with Core Power, a UK startup that intends to develop marine nuclear power plants.

“It is on track for an operating license by the US Nuclear Regulatory Commission… We think 2029 is when it will be ready, which is as soon as anything else will come to market,” said Mikal Bøe, CEO of Core Power. He added that he hopes to start building an order book in 2027 or 2028.

Ball said two target markets for eVinci reactors are data centers and the oil and gas industry, both onshore and offshore. He highlighted that operating multiple microreactors together would make data centers more resilient than with a single power source.

Microreactors are also considered promising for mining, especially for extracting cobalt, manganese and other critical minerals located in remote areas, said Ian Farnan, professor of nuclear and earth materials at the University of Cambridge.

He explained: “You need to cut 1,000 tons of rock to get one ton of product. This will change how a mine operates. Currently, we use diesel, which has high costs and carbon emissions, in addition to complicated logistics for remote locations. A reactor that lasts 10 to 20 years would solve the energy issue.”

Nasdaq-listed Nano Nuclear Energy hired Farnan to design a low-pressure coolant microreactor, expected to hit the market in 2031.

Other companies leading the new microreactor industry include New York-listed BWX Technologies, which already builds nuclear reactors for U.S. Navy submarines and aircraft carriers, and X-energy, which raised $500 million in September from investors like Amazon and Ken Griffin, founder of hedge fund Citadel.

Both companies were selected for Project Pele, a U.S. Department of Defense commission for a portable nuclear reactor that could be airlifted and operate for several years before being moved again.

However, J. Clay Sell, CEO of X-energy, stated that the microreactor market is “still emerging.”

“We’ve probably invested as much as anyone in the industry,” he said. “But as reactors shrink in size, the economics become more challenging. It is necessary to reach a larger scale to make them economically viable.”

Bøe stated that the microreactors will be price competitive when production lines are expanded. “With an order book of 60 to 120 reactors, you achieve an economy of scale,” he said, adding that the goal is to produce electricity for $100 to $150 per megawatt-hour.

“It is not competitive on a grid scale, but it is very competitive for ports, terminals, petrochemical facilities, islands and remote locations,” he said. “The cost of getting diesel and gas to these places is prohibitive.”

But there are questions about how to build, transport and operate microreactors safely, said Ronan Tanguy, safety and licensing program leader at the World Nuclear Association.

Regulators still need to create rules about remote operation, security against cyberattacks, transportation, and whether reactors should be fueled in factories or on site. Due to their smaller size, they can become easier targets for nuclear fuel theft.

Westinghouse said the eVinci would meet the same aircraft impact tests applied to larger reactors, but Tanguy noted that many existing rules for reactors are “disproportionate or not applicable to microreactors.” He highlighted that it would be very difficult to deliberately hit such a small target with an aircraft.

“The International Atomic Energy Agency will likely issue general safety standards, which are often incorporated into national regulations,” he said. “This won’t be quick. But if there is a will, it can be done, although it requires a lot of work.”

With information from the Financial Times*