Mitsubishi Nuclear Energy Systems (MNES) is the U.S. subsidiary of Mitsubishi Heavy Industries, Ltd. one of the worlds leading manufacturers of nuclear and conventional electric power plants and replacement components (reactor vessel head and steam generator). Mitsubishi is a fully-integrated nuclear power plant and steam generator supplier, providing planning, design, manufacturing, construction and plant maintenance for its utility customers.

Mitsubishi Heavy Industries, Ltd. has a history of leadership in pressurized water reactor development in Japan. Our research and development efforts and real-world experience led to the U.S. Advanced Pressurized Water Reactor (US-APWR), the most powerful and efficient power plant in the world.

The US-APWR grew out of the "Third Phase Improvement and Standardization Program" for nuclear power plants, funded by Japans Ministry of International Trade and Industry (MITI). The new design takes into account recent utility requirements regarding safety, reliability, economy and compatibility with the environment. Improvements in the US-APWR over earlier designs includes a thermal efficiency of 39%, the highest in the industry; a 20% reduction in plant building volume; and greater economy by increasing power generation capacity to the 1,700 megawatt class.