TerraPower gets OK to start construction of its first nuclear plant

"The TerraPower design, which it calls Natrium and has been developed jointly with GE Hitachi, has several novel features. Probably the most notable of these is the use of liquid sodium for cooling and heat transfer. This allows the primary coolant to remain liquid, avoiding any of the challenges posed by the high-pressure steam used in water-cooled reactors."

"Natrium is also a fast-neutron reactor, which could allow it to consume some isotopes that would otherwise end up as radioactive waste in more traditional reactor designs. The reactor is also relatively small compared to most current nuclear plants (245 megawatts versus roughly one gigawatt), and incorporates energy storage."

"Rather than using the heat extracted by the sodium to boil water, the plant will put the heat into a salt-based storage material that can either be used to generate electricity or stored for later use. This will allow the plant to operate around renewable power, which would otherwise undercut it on price."

The US Nuclear Regulatory Commission granted its first construction approval in nearly a decade to TerraPower for a sodium-cooled reactor project in Kemmerer, Wyoming. The Natrium reactor, developed jointly with GE Hitachi and backed by Bill Gates, incorporates several innovative features. It uses liquid sodium for cooling instead of high-pressure steam, eliminating certain challenges while introducing sodium reactivity risks. As a fast-neutron reactor, it can consume isotopes that typically become radioactive waste. The plant is relatively small at 245 megawatts and includes salt-based energy storage that can generate electricity or store heat for later use, allowing operation alongside renewable energy sources and temporary output up to 500 megawatts.

Read at Ars Technica