Several companies in the United States are advancing the development of small modular reactors as a new approach to nuclear energy. The aim is to reduce capital costs and improve flexibility in deployment, according to a report by the U.S. Energy Information Administration.

The report noted that the United States currently operates about 98 gigawatts of nuclear generating capacity, but very little new capacity has been added in recent decades due to high capital costs and lengthy licensing processes. Small modular reactors are being seen as a solution to these challenges.

Unlike traditional large-scale nuclear reactors, which typically have a capacity between 550 megawatts and 1,500 megawatts per unit, small modular reactors have a capacity of about 300 megawatts per unit or less.

Their modular design allows components to be factory-assembled and shipped to construction sites, which could help reduce construction time and costs. The U.S. Energy Information Administration stated that several companies are developing new designs aimed at reducing capital costs and increasing siting flexibility, addressing challenges associated with traditional nuclear power.

Different small modular reactor designs employ a variety of cooling technologies, including light water, gas, liquid metal and molten salt. Some designs use high-assay low-enriched uranium, enriched between 5 per cent and under 20 per cent uranium-235, compared to the lower enrichment used in current reactors.

This allows for improved efficiency, smaller reactor size and reduced nuclear waste. A subset of small modular reactors, known as microreactors, generally have a capacity of 20 megawatts or less and can operate independently or as part of a microgrid. These smaller systems are particularly useful for remote areas or locations that lack the infrastructure to support large nuclear plants.

The report highlighted that small modular reactors and microreactors can also support emerging applications such as powering artificial intelligence systems, data centres and other industrial activities where grid connectivity may not be required.

It also detailed advanced reactor types such as high-temperature gas reactors, molten salt reactors and sodium-cooled reactors, which can operate at higher temperatures and offer potential improvements in efficiency and industrial use.

Government support for small modular reactor development in the United States has been increasing. In March 2025, the Department of Energy reissued a tender for USD 900 million in funding to promote these technologies.

The Department also launched the Energy Reactor Pilot Program in June 2025 to accelerate testing of advanced reactors. The report suggests that small modular reactors and microreactors could play a key role in the future of nuclear energy by offering more flexible, cost-effective and scalable solutions compared to traditional nuclear power plants.

ANI