My inquiry about the miniaturization of nuclear reactors received this AI reply...
As of late 2025, the miniaturization of nuclear reactors is an active area of development, with several countries moving toward commercial deployment, though challenges with cost and licensing remain. Significant progress is being made on Small Modular Reactors (SMRs) and even smaller microreactors, with governments and private companies investing heavily in the technology.Operational and near-term deployment
While full commercial viability is still pending for most projects, some countries have operational units or are near deployment.
- Russia: The world's first floating nuclear power plant, the Akademik Lomonosov, has been powered by two 35 MWe SMRs since 2020. The Russian state-owned company Rosatom is planning a land-based SMR in Sakha, expected to be completed by 2028.
- China: A commercial 210 MWe SMR has been operating since 2023. Another project, the ACP100 reactor, began construction in 2021 with a planned start-up in 2026.
- United States: Several projects are in the works with the aid of federal funding from the Department of Energy (DOE)
- Holtec International is developing two SMRs in Michigan, with operations scheduled to begin in 2030, pending regulatory approval
- The DOE certified NuScale Power's 77 MWe SMR design in 2023. However, a proposed project in Idaho was canceled in 2023 due to cost escalations.
- The Department of Defense has initiated Project Pele to develop a mobile microreactor for military use, aiming for a prototype by 2027. SMRs vs. microreactors
Miniaturized reactors fall into two main categories, each serving different power needs:
- Small Modular Reactors (SMRs):
~> Power output: Typically produce 50 to 300 MWe (megawatts of electric power), roughly a third of the output of conventional reactors.
~> Construction: Designed for factory fabrication, which promises lower costs and faster build times compared to custom-built large reactors.
~> End use: Suited for supplementing existing grids or providing power to energy-intensive industrial facilities and large data centers.
- Microreactors:
~> Power output: Even smaller, generating up to 10 MWe.
~> Portability: Compact enough to be transported by truck.
~> End use: Intended for remote locations, military bases, disaster relief, and other scenarios that require a transportable, self-sustaining power source.
Key trends driving development
Several factors are fueling the momentum behind miniaturization:
~> Decarbonization: SMRs and microreactors offer a reliable, zero-carbon energy source that can complement intermittent renewables like solar and wind.
~> Energy security: Deploying decentralized, compact reactors reduces reliance on long, vulnerable power grids, particularly for military applications and remote communities.
~> Industrial demand: Large technology companies like Amazon and Google are investing in SMRs to power energy-hungry data centers.
~> Financial backing: Public and private investment is growing, with the DOE allocating hundreds of millions of dollars to aid in deployment.
Challenges and criticisms
Despite the progress, significant hurdles remain for the widespread adoption of miniaturized reactors:
~> Cost competitiveness: Some critics argue that SMRs are still more expensive per kilowatt-hour than larger plants or renewable energy sources, and mass production is needed to achieve true cost savings.
~> Licensing and regulation: The approval process for new designs can be lengthy and costly, especially with varying international standards.
~> Waste management: Some studies suggest that certain SMR designs could produce more radioactive waste per unit of electricity than conventional reactors, posing a challenge for long-term storage.
~> Uncertainty: As of late 2025, the industry remains in its early stages, and the full commercial and economic viability of SMRs and microreactors has yet to be proven at scale.
