SANMEN, Zhejiang, April 19 (Xinhua) -- China on Sunday started the construction of its first third-generation pressurized water reactors using AP 1000 technologies developed by U.S.-based Westinghouse.

The reactors, located in Sanmen of east China's Zhejiang Province, will also be the first in the world using such technologies.

The Sanmen Nuclear Power Plant will be built in three phases, with an investment of more than 40 billion yuan (5.88 billion U.S. dollars) injected in the first phase.

The first phase project will include two units each with a generating capacity of 1.25 million kw.

The first generating unit will be put into operation in 2013, and the second, in 2014. The plant will eventually have six such units.

"It is the biggest energy cooperation project between China andthe United States," said Zhang Guobao, vice minister in charge of the National Development and Reform Commission and also head of the National Energy Administration.

"It will contribute to the human kind's peaceful use of nuclear power," he said.

China launched bidding in 2003 for its nuclear power stations of the third generation. Foreign companies including Westinghouse, France's Areva and Russia's AtomStroy Export are major bidders.

Westinghouse became the winner after China signed a memo with the United States on the introduction and transfer of third-generation nuclear power technologies in December 2006.

The final agreement was inked between China's State Nuclear Power Technology Corporation and Westinghouse in July 2007, according to which China will buy four third-generation pressurized water reactors from Westinghouse. The agreement also involves technology transfer to China.

Two of the four pressurized water reactors will be installed in Sanmen of Zhejiang Province and two in Haiyang City, eastern Shandong Province.

William Poirier, vice president of Nuclear Power Plants China of Westinghouse Electric Company, said China has a sound nuclear power security system with a strict supervision work.

He said he believed China can replicate the experiences of the third-generation nuclear power technologies and build more such stations.

China's mainland has 11 nuclear reactors at six plants, all on the east coast, with a combined installed capacity of 9.07 million kw.

To meet its fast economic growth, China plans to develop more nuclear power. The country plans to have 40 million kw of installed nuclear capacity on its mainland by 2020, which would be4 percent of projected electricity supply capacity, or double the current level.

Of the 11 reactors, three use domestic technologies, two are equipped with Russian technology and four with French technologies, and two are Canadian designed. All the 11 reactors employ second-generation nuclear power technologies.

Speaking at Sunday's inauguration ceremony of the first-phase project of the Sanmen Nuclear Power Plant, Chinese Vice Premier Li Keqiang urged making more efforts to develop new energy to ensure the country's energy security and boost economic growth.

He underscored innovation as the key to nuclear power development, calling for enterprises to adopt advanced technology and enhance self-innovation.

He said it was inevitable that China would need to improve energy structure and enhance energy conservation and emission cuts when resources and environment issues took their toll on economic development.