Benefits of the US-APWR
The US-APWR design replaces the 2-train emergency core cooling system used in conventional plants with a 4-train system with no header or connecting piping. This simplified design enhances the redundancy and independency of the system. The refueling water storage tank, a component placed outside the containment vessel in conventional plants, is located inside the containment vessel in the US-APWR in order to avoid the switchover operation from ECCS injection to recirculation during loss-of-coolant accidents.
A new high-performance accumulator system is introduced to regulate the emergency core cooling system design. It incorporates the functions of both traditional accumulators and low-pressure injection pumps.
The US-APWR replaces the traditional diesel generators with more reliable, air-cooled, fast-start gas turbine generators. This ensures immediate backup power will be supplied to the safety and cooling systems in the case of a station blackout event or other serious accidents.
All of systems have been extensively tested and verified in operating plants in Japan. Safety is Mitsubishi’s first priority.