The deployment of microreactors in the short-to-medium term could support energy markets not available to large nuclear plants, but some significant challenges must be overcome to capture new market shares. In the longer term, these systems will be able to contribute to decarbonization efforts, according to an assessment conducted by the U.S. Department of Energy's Idaho National Laboratory (INL).

Potential deployment of this subset of small modular reactors of 1-20 MWe capacity, which includes light water, molten salt, gas-cooled, metal-cooled fast and heat pipe reactors, in 63 nations was evaluated for the 2030-2050 timeframe. By 2030, initial deployments of these systems could potentially expand the nuclear contribution in North America and Western Europe, areas that would otherwise show low future nuclear growth.

Mid-term deployments beginning around 2035 could see expansion in Eastern Europe and Asia, where energy infrastructures are under development, and to support new nuclear markets in emerging economies. Feasible deployments during 2040-2050 could target urban markets and megacities lacking access to energy and susceptible to climate change. Microreactors could also be of value for disaster relief by replacing portable diesel generators and for fostering low-carbon shipping operations.

Microreactor top-down global projection (GWe capacity). Source: INLMicroreactor top-down global projection (GWe capacity). Source: INL

Consideration of low carbon scenarios suggests that microreactors could contribute to closing the gap on zero carbon by 2050 by replacing fossil sources for electric and non-electric uses and assisting the transition to renewable energy sources. Filling these gaps could require hundreds of microreactor units by 2040 and thousands by 2050. Remaining technology challenges encompass staffing, surveillance and fuel security issues and cyber risks since remote and semi-autonomous use are positioning nuclear generation for novel settings.

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