Nuclear Power Technology Development Section

Light Water Reactors

Light Water Reactors
In operation 361
Under construction 16
Number of countries with LWRs 27
Generating capacity, GW(e) 325.5

Tokyo Electric Power Company's Kashiwazaki-Kariwa Units 6&7 Two Advanced BWRs, which started commercial operation in November 1996 and July 1997 respectively. These plants were constructed by an international joint venture consisting of General Electric Nuclear Energy (USA), and Hitachi, Ltd, and Toshiba Corporation (Japan). (Credit: TEPCO )

In the Republic of Korea, the benefits of standardization and construction in series are being realized with the 1000 MWe Optimized Power Reactor (OPR) units. In addition, the development of the Korean Next Generation Reactor, now named the Advanced Power Reactor 1400 (APR-1400), was started in 1992, building on this experience. Recent development of the APR-1400 focused on improving availability and reducing costs. A power level of 1400 MWe has been selected to capture economies-of-scale. In March 2001, KEPCO started the Shin-kori 3,4 project for the APR1400. KAERI has a project to construct a one-fifth scale prototype (65 MWth) of the SMART integral PWR.

Benefits of standardization and construction in series are also being realized in Japan with the ABWR units . Future ABWRs are expected to achieve a significant reduction in generation costs relative to the first ABWRs. The means for achieving this cost reduction include standardization, design changes and improvement of project management, with all areas building on the experience of the ABWRs currently in operation. In addition, a development programme was started in 1991 for ABWR-II, aiming to further improve and evolve the ABWR, with the goal of significant reduction in power generation cost relative to a standardized ABWR. The power level of ABWR-II has been increased to 1700 MWe, and benefits of economies-of-scale are expected. Commissioning of the first ABWR-II is foreseen in the late 2010s. Also in Japan, the basic design of a 1530 MWe advanced PWR has been completed by Mitsubishi Heavy Industries and Westinghouse for the Japan Atomic Power Company's Tsuruga-3 and -4 units.

In France and Germany, Framatome ANP has designed a 1545 MW(e) European Pressurized Water Reactor (EPR), which meets European utility requirements. The EPR's higher power level relative to the latest series of PWRs operating in France (the N4 series) and Germany (the Konvoi series) has been selected to capture economies of scale. Site excavation is underway for the first EPR, the Olkiluoto-3 unit in Finland. Commercial operation is planned for mid-2009. Electricite de France is planning to construct an EPR at Flamanville (unit 3). Start of construction is projected for 2007 with grid connection in 2012.

In Germany, Framatome ANP with international partners from Finland, the Netherlands, Switzerland and France is developing the basic design of the SWR-1000, an advanced BWR with passive safety features.

In the Russian Federation, efforts continue on evolutionary versions of the currently operating WWER-1000 (V-320) plants. This includes the WWER-1000 (V-392) design, of which two units are planned at the Novovoronezh site, and WWER-1000 units planned in China, India and the Islamic Republic of Iran. Development of a WWER-1500 design has been initiated. Development is also on-going on a mid-size WWER-640 with passive safety systems, and on an integral design with the steam generator system inside the reactor pressure vessel.

In the USA, designs for a large sized advanced PWR (the Combustion Engineering System 80+) and a large sized BWR (General Electric’s ABWR) were certified in May 1997 by the U.S Nuclear Regulatory Commission. Westinghouse’s mid-size AP-600 design with passive safety systems was certified in December 1999. The Westinghouse 1090 MW(e) plant called the “AP-1000”, which applies the passive safety technology developed for the AP-600 with the goal to reduce the capital costs through economies-of-scale received Design Certification from the U.S. NRC in 2006. Westinghouse is also designing a 335 MWe integral PWR called IRIS. Presently, the design is in the Pre-Application Review stage with the U.S.NRC. Westinghouse plans to submit an application for design certification to the NRC.

General Electric is designing a 1550 MW(e) ESBWR applying economies-of-scale together with modular passive safety systems. The design draws on technology features from General Electric’s ABWR and from their earlier 670 MW(e) simplified BWR with passive systems. The ESBWR is being reviewed by the U.S NRC for design certification.

In China, the China National Nuclear Corporation (CNNC) is developing the CNP-1000 plant, which incorporates feedback of experiences of design, construction and operation of Qinshan and the Daya Bay NPPs.

Several countries are developing innovative LWR designs, which represent a greater departure from current systems, and may require a prototype or demonstration plant as part of the development programme. Innovative LWR designs include integral designs in which the reactor core and steam generator are housed in the same pressure vessel, and designs operating thermodynamically in the super-critical regime (above 22 MPa and 374 C). Thermodynamically supercritical water-cooled systems have been selected for development by the Generation IV International Forum.

The latest status report on advanced LWRs, TECDOC-1391, covering both evolutionary and innovative designs was published in 2004.