Supercritical Water Reactor

The supercritical water reactor, or SCWR, is a concept Generation IV reactor designed as a light water reactor that operates at supercritical pressure, above 22.1 megapascals. Above this pressure the water in the reactor core transitions past 374 degrees Celsius from liquid-like to steam-like properties without undergoing a distinct boiling phase change, which the design uses to reach a thermal efficiency of around 45 percent, compared with roughly 33 percent for current light water reactors. As of 2012 the concept was under investigation by 32 organizations across 13 countries, with typical designs targeting more than 1,000 megawatts of electrical output at outlet temperatures of 500 to 625 degrees Celsius.