The nuclear power station is located 7 kilometres east of Dapeng in the municipality of Shenzhen, on the coast of Daya Bay in China's Guangdong province. It is about 45 kilometres from the city centre of Shenzhen, and about 50 kilometres from Tsim Sha Tsui in Hong Kong.
This distance is in line with international practice, with most nuclear power stations in other parts of the world located some 30 to 50 kilometres from the nearest city centre. The site was chosen after careful analysis of detailed studies that indicated suitable seismological and geological conditions, low risk of meteorological hazards such as flooding, tidal waves and severe storms, as well as adequate water cooling sources, reliable power grid interconnection, adequate distance from the consumers, sufficient distance from commercial flight paths, major cities and hazardous industrial installations and a low environmental impact.
Daya Bay comprises two identical 984 MW (gross) pressurised water reactor type electricity generating units. This type of reactor has a long track record of safe and reliable operations. At the end of 2007, of the 441 commercial nuclear reactors in operation in the world, 265 were of the pressurised water reactor type.In the nuclear island, heat is produced by the nuclear reaction in the pressurised water reactor and delivered as water to the interface with the conventional island, where it is turned into steam.
In the conventional island, steam at high pressure passes through a multi-stage turbine which is coupled to an electric generator. The steam leaving the turbine then passes through a condenser where the heat is removed, causing it to condense as water. This water is pumped back to the nuclear island to be turned again into steam.
At Daya Bay, cooling water for the condenser is taken from the sea. Water used in the nuclear island is physically separated from the water used in the conventional island, and is in turn separated from the water taken from the sea for the condenser. This physical separation provides a barrier to any escape of radioactivity into the environment.
Daya Bay requires about 900 staff members for its operation. About 700 of them are technical staff. More than 90 percent have completed university education and 70 percent are professionally qualified. Daya Bay still maintains a small team of international advisors, most of whom are French engineers seconded from the French national power company EDF.All staff members working in the power station must undergo stringent training on nuclear safety.
All operators must obtain a licence issued by the National Nuclear Safety Administration before they can work in the control room, and sit a re-qualifying examination every two years. They also have to attend simulator training to keep themselves abreast of the latest technologies and practices.
International and local contractors engaged to work on plant projects and refuelling overhauls are also subject to stringent training in line with international practice.
To learn from the best practices around the world, Daya Bay organises regular exchanges and seminars with international bodies such as the World Association of Nuclear Operators and the International Atomic Energy Agency, as well as with its sister stations in France, South Africa, Belgium and China.
The Daya Bay reactors are standard 3-loop French PWR units supplied by Framatome, with GEC-Alstom turbines. Electricite de France (EDF) managed construction, starting August 1987, with the participation of Chinese engineers. Commercial operation of the two units was in February and May 1994. There were long outages in 1994-96 when Framatome had to replace major components. Reactor vessel heads were replaced in 2004. The plant produces about 13 billion kWh per year, with 70% transmitted to Hong Kong and 30% to Guangdong.
Daya Bay and Lingao together comprise the 'Daya Bay nuclear power base' under the common management of Daya Bay Nuclear Power Operations & Management Co (DNMC), part of China Guangdong Nuclear Power Group (CGNPC). Framatome is now Areva NP.
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