Westinghouse Westinghouse
Energy Systems

AP1000® Reactor Design

The Westinghouse AP1000 pressurized water reactor yields considerable capital savings and lower maintenance costs delivering safe, efficient, more economical nuclear power solutions across the world.

The AP1000® reactor is a two-loop pressurized water reactor (PWR) that uses a simplified, innovative, and effective approach to safety. With a gross power rating of 3,415 megawatts thermal (MWt) and a nominal net electrical output of 1,110-megawatt electric (MWe), the AP1000 reactor, with a 157-fuel-assembly core, is ideal for new baseload generation.

Simplified Reactor Design

Simplification was a major design objective of the AP1000 reactor. Simplifications in overall safety systems, normal operating systems, the control room, construction techniques, and instrumentation and control systems provide a technology that is easier and less expensive to build, operate, and maintain. These simplifications yield fewer components, cable, and seismic building volume, all of which contribute to considerable savings in capital investment, and lower operation and maintenance costs. At the same time, the safety margins for the AP1000® reactor have been increased dramatically over currently operating reactors.

AP1000 statistics

The Technology

The AP1000 PWR is comprised of components that incorporate many design improvements distilled from 50 years of successful operating nuclear power plant experience. The reactor vessel and internals, steam generator, fuel and pressurizer designs are improved versions of those found in currently operating Westinghouse-designed PWRs. The reactor coolant pumps are canned-motor pumps, the type used in many other industrial applications where reliability and long life are paramount requirements.

Innovative AP1000 Reactor Design, Services, and Equipment

  • The most advanced, proven Generation III+ technology available
  • Only available reactor with fully passive safety systems and 72+ hour coping after station blackout
  • Dramatically reduced start-up test programs from 10 months to 5 months or less (including 1 month at full power)
  • Industry and national performance records set for first and second operating cycles
  • Industry and national performance records set for first-cycle refueling outages (28 days)
  • Industry and national performance records set for second-cycle refueling outages (19 days)
  • Advanced chemical-free load-following capability
  • Reactors used in both baseload and load-follow modes with ramp rates of +/- 5% per minute down to 15% of full power