The final safety evaluation report on NuScale Power’s small modular reactor (SMR) design has been issued by the U.S. Nuclear Regulatory Commission (NRC). Completion of the agency’s Phase 6 review is a first for an SMR and puts NuScale on track to receive a full design certification from the regulator by August 2021.

These SMRs can produce about 60 MW of energy, enough to power more than 50,000 homes. Each power plant can house up to 12 modules, which will be factory-built and about a third of the size of a large-scale reactor. The advanced light water reactor is designed to passively cool itself without the need for additional water, power or operator action. This safety feature could lead to a reduction in the emergency planning zone to the site An artist’s rendering of the SMR power plant. Source: NuScaleAn artist’s rendering of the SMR power plant. Source: NuScaleboundary and also reduce the footprint of the power plant.

A unique arrangement of battery arrays in the NuScale design increases DC power reliability for post-accident monitoring systems. Compact helical coil steam generators are used to provide increased heat transfer surface area in a small volume with very low pressure drop to maximize natural circulation flow. The once-through counter-flow design enables the generation of steam superheat and good thermal efficiency without the use of reactor coolant pumps. The high strength steel containment immersed in the cooling pool acts as a heat exchanger to provide reactor cooling and pressure control, eliminating the requirement for containment spray systems for cooling.

Upon receiving full certification, utilities will be able to reference the design when applying for a combined license to build and operate the new reactors in the U.S. The first of the NuScale SMRs is scheduled to come online in 2029 at the U.S. Department of Energy’s Idaho National Laboratory facility, with 11 more to follow in 2030.

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