Four trailblazing microreactors in the new era of nuclear

Microreactors, referred to by some as ‘nuclear batteries,’ are squarely in the spotlight at this year’s Powergen International.

Four trailblazing microreactors in the new era of nuclear
(Image: POWERGEN International)

By Pamela Largue, Power Engineering International

Microreactors, referred to by some as ‘nuclear batteries,’ are squarely in the spotlight at this year’s POWERGEN International.

Discussions explored the latest technologies, popular applications and the unique business models making them viable.

Four microreactors stood out as trailblazers in the sector:

1 – eVinci Microreactor from Westinghouse Electric Company

It’s a heat pipe reactor that can produce 5MWe with a 13MWth core design. The reactor core is designed to run for eight or more full-power years before refueling.

The reactor is fully factory-assembled and transportable in shipping containers via rail, barge, and truck. Customers will likely be industrial actors and remote communities, with applications ranging from industrial heat and power, military, microgrids, cogeneration and hydrogen production.

The first eVinci microreactor is scheduled to be up and running by 2029.

2 & 3- ZEUS and ODIN from NANO Nuclear Energy

NANO Nuclear Energy is developing ZEUS, a solid core battery reactor, and ODIN, a low-pressure coolant reactor.

The ZEUS microreactor prototype is designed to harness thermal energy for direct heat applications or to convert it into electric power. This allows for diverse applications, ranging from heating to electricity generation.

The ODIN reactor will operate at higher than conventional water-cooled reactor temperatures, which will boost resilience and conversion efficiency in generating electricity.

According to NANO, the ODIN design aims to take advantage of the natural convection of coolant for heat transfer to the power conversion cycle at full power and for decay heat removal during reactor shutdown, operational transients, and off-normal conditions.

Both microreactors use High-Assay, Low-Enriched Uranium (HALEU) fuel, are modular, and are easily transportable.

4 – Micro Modular Reactor (MMR) Energy System from Ultra Safe Nuclear

MMR is a 4th Generation nuclear energy system that is being licensed in Canada and the U.S. and is touted as the first ‘fission battery’ in commercialization.

Ultra Safe Nuclear has established an order book for first users, with demonstration units scheduled for first nuclear power in 2026.

The reactors are being developed for government applications, as well as for use in space and are designed to offer energy security and decarbonization for hard-to-abate sectors, and remote communities.

The reactor is modular and scalable and operates on ceramic-based TRISO fuel.

Big hurdles for micro technology

James Walker, CEO of NANO Nuclear Energy, stated that “nuclear is getting smaller…you could produce potentially thousands of these per year.”

And while this is indeed the case, there are some significant hurdles to overcome before production can increase, said Walker.

These hurdles include:

  • Cost – Microreactors mainly compete with diesel generators, a much more cost-effective option. To become more competitive, many more of these solutions need to be sold to create economies of scale and this will take time. To be viable, the industry is targeting 12-14c per KWh.
  • New business models are needed: NANO Nuclear is leasing the energy produced to remove capital cost from the customer, and other commercial models are being explored whereby communities can act as developers or part equity owners.
  • Skilled workforce required: The question of who will man these reactors on site must be answered, especially as some customers opt to not operate the system themselves.
  • A well-functioning, domestic supply chain and secure fuel sources are critical to the success of the industry.

Microreactors have a way to go before they can take their place in the energy mix. However, what is clear is that they aren’t here to compete with big build nuclear. Their value lies in their niche applications, which is where they can make the biggest impact.