Small modular nuclear reactors (SMRs) saw an important landmark in the US last month when the Nuclear Regulatory Commission finally approved the design of a first-of-its-kind SMR from the Oregon-based nuclear firm NuScale Power.
The International Atomic Energy Agency (IAEA) defines SMRs as advanced nuclear-fission reactors that have a power generation capacity of up to 300MW per unit – around a third of the capacity of traditional reactors. Their perceived benefits derive from the ‘small’ and ‘modular’ nature of their design. Their diminutive size means they can be sited at locations unsuited to larger nuclear power plants. Prefabricated units of SMRs could be manufactured and then shipped and installed on site, potentially making them more affordable to build than traditional reactors, which are typically custom-designed for specific places, often resulting in construction delays. The technology is designed to save on cost and construction time, and be deployed incrementally to match increasing energy demand.
You wrote “Their diminutive size means they can be sited at locations unsuited to larger nuclear power plants.”
“Diminutive” is inaccurate. The size of the land required for a 300 MW reactor will not be 30% of the land required for a 1,000 MW reactor. System areal requirements do not scale linearly.
It seems the SMR developers are doing away with the large concrete pressure containment vessel to make them smaller. Radiation containment is supposed to be done by improved primary and secondary loop design and by burying the reactor underground.