What are microreactors?

A microreactor is a small nuclear reactor that can operate as part of the electric grid, independently from the electric grid, or as part of a microgrid to generate up to 20 megawatts thermal energy that can be used to generate electricity and provide heat for industrial applications. Most of these small reactors are designed to be portable – many could be hauled by a semitractor-trailer. Microreactors are 100 to 1,000 times smaller than conventional nuclear reactors, while small modular reactors (SMRs) range from 20 to 300 megawatts.

Microreactors offer a combination of reliability and operational flexibility that no other small generating system can match. They are expected to operate for years without refueling. Renewed interest in these very small reactors is driven by a number of factors, including the need to generate power on a small scale in remote locations, at deployed military installations, and in locations recovering from natural disasters.

The U.S. Department of Defense is pursuing the concept as its military operations become more energy intensive and require portable, dense power sources. Remote, rural communities in the U.S., many of which fly or truck in diesel to run generators, are considering microreactors since they could generate power on-site. Their potential use as sources of industrial process heat opens up potential new markets for zero-carbon energy for desalination, hydrogen production and other industries.

INL is working with developers, private industry, regulators, universities and others to develop, demonstrate, test and validate this new generation of microreactors. As part of its research mission, INL is also helping develop new fuels for microreactor designs, many of which will use low-enriched uranium with higher concentrations of uranium-235 than the fuel used in today’s commercial power reactors.

Why are people excited about microreactors?

What are some characteristics of microreactors?

Who is developing microreactors?

A number of private sector companies have microreactor initiatives.

The Gateway for Accelerated Innovation in Nuclear (GAIN) and Third Way, with the help of the United States Nuclear Infrastructure Council (USNIC), published an Advanced Nuclear Directory that lists developers and suppliers engaged in advanced nuclear energy.

How will INL and NRIC support microreactor demonstrations?

What are the different types of nuclear reactors?

Idaho National Laboratory