The project in May 2008 became the first large-scale offshore wind project approved by China's National Development and Reform Commission, which says the country can achieve about 100 GW of wind in offshore areas with water depths of ten metres, 300 GW in areas of 20 metre depth and 490 GW in areas of 30 metre depth (Windpower Monthly, May 2009). The project, by developer Shanghai Dong Hai Wind Power, is to comprise 34 Sinovel 3 MW turbines, the largest models developed by a Chinese company, with planned annual generation of 267 GWh. The distance of wind turbines from Shanghai's Donghai Bridge, in central-eastern China, will range from one to four kilometres, in waters of average ten-metre depth. The average annual wind speed is 8.4 m/s at 90 metres above the sea surface, the height of the turbines' hubs. The project's backers are China Datang Corporation, Shanghai Green Environment Protection Energy, China Guangdong Nuclear Wind Power and China Power International New Energy Holding. Investment totals CNY 2.4 billion ($352 million). The turbines feature individual pitch control, variable speed and doubly fed generator technologies. The rotors have a diameter of 91.5 metres. Full commissioning of the wind farm is expected by the first half of next year.