The ABWR is the evolutionary design of the last generation of Boiling Water Reactors (BWR) built in the U.S. It carefully blends the best features of worldwide operating BWR plants with new and improved safety and performance systems, while systematically reducing capital costs and incorporating features into the plant design that will make maintenance significantly easier and more efficient.

ABWR IMPROVEMENTS OVER EXISTING BWR TECHNOLOGY Feature Constructability Performance Safety Modularization Reactor Pressure Vessel Reactor Recirculation System Fine Motion Control Rod Drive System   Emergency Core Cooling System   Digital Control Systems   Turbine Generator

The ABWR design uses a single-cycle, forced circulation, boiling water reactor. The design incorporates the best features of the BWR designs in Europe, Japan and the U.S., and uses improved electronics, and computer, turbine and fuel technology, resulting in improved plant availability, operating capacity, safety and reliability.

One of the most notable safety improvements was the moving of the water circulation pumps inside the reactor which enhanced plant operations while lowering construction costs and radiation exposure to outage workers.

Other safety enhancements include:

The use of more than 200 modules per unit to reduce construction duration, costs and rework

A more robust, long-lived reactor pressure vessel head using forged rings instead of welded plates

Internal recirculation pumps to enhance safe operations while reducing plant size, cost, and maintenance

More capable and multiple integrated emergency core cooling systems to protect against possible loss of coolant situations

Greater operator control as a microprocessor-based digital control system and a mechanical, ball screw continuous drive system provide much finer adjustment of a control rod's position

A more thermally efficient, higher output turbine generator

The ABWR is truly an advancement over the units that are presently in operation in the U.S.