On the one hand, Shanghai has rushed into construction in a bid to be a national leader catching up with overseas counterparts. On the other hand, it has had to be cautious not to allow inexperience to thwart efficient projects.

"Wind farms are a capital-intensive investment," said Luo Tianyu, project director of Institute of Scientific and Technical Information of Shanghai.

"Construction of offshore wind farms accounts for 90 percent of total investment, while operational costs form the balance," Luo said. "The municipal government is taking cautious steps forward to avoid unnecessary losses."

Overseas countries usually take five to 10 years to carry out exhaustive studies on wind power, wind farm design and environmental impact testing in order to avoid rebuilding or relocation due to poor planning.

However, the decision to build offshore windmills in Shanghai was made four years ago and construction of the Donghai wind farm was started in September 2008.

Still, industry experts are optimistic about the prospects.

"The Donghai farm was a good start for the application of clean energy in Shanghai," said Li Chonghe, vice general manager of Shanghai Electric Power Co Ltd, the city's main power supplier.

Shanghai Electric Power said construction of the second phase of the Donghai wind farm has been approved for the west side of the bridge. Total capacity of the second phase is estimated at about 100 megawatts.

Another four offshore wind farms are also in the pipeline: one in the Pudong New Area, one in Chongming County and the other two in the Fengxian District. The total capacity of wind power could reach 1,100 megawatts after these farms are up and running.

On the technical front, Shanghai Electric Group completed construction of China's biggest offshore wind turbine last month. The 3.6-megawatt turbine has passed tests and is able to generate 9 million kilowatt-hours a year. The company has identified offshore wind power as one of its top priorities and aims to sell wind turbines valued at 10 billion yuan by 2011.

State grid

Supporting facilities are also vital in the city's new energy drive, experts said.

"A stronger state grid and well-established market systems are necessary for sustainable development," said Sigrid Hjornegard, deputy minister of the Norwegian Petroleum and Energy Ministry.

In Europe, an electric transaction system enables participants from consumers to wind farm operators to derive benefit from wind generation. Local governments provide most of the up-front investment to kick projects off.

"Instead of taking all the responsibility on themselves, governments would be better advised to try to attract more private capital through preferential tax policies and administrative support, such as streamlining the application process and certification tests," said Luo.

Shanghai is also planning another eight onshore windmill farms in Nanhui and Fengxian districts as well as Chongming County.