Could Wind Power China's Energy Future?

Wind energy could provide all of China's electricity demand projected for the year 2030, about twice China's current consumption, says a new study published in the journal Science.

China now emits more CO2 than any other nation -- about 20 percent of the world's total -- but it is also the fastest growing market for wind power.

Recent laws even encourage the development of some renewable energy.

Even so, today 80 percent of China's energy comes from burning coal, and only 0.4 percent from wind.

"China's fossil energy consumption is so large that a large-scale conversion to renewable energy there is critical for addressing climate and air pollution problems," said Mark Jacobson of Stanford University, who was not a part of the study.

The details of this study provides practical information that policy makers and developers can use, he added.

Michael McElroy and colleagues at Harvard University in Cambridge, Mass., and Tsinghua University in Beijing estimated the potential for wind energy across China. They excluded unfavorable areas, such as those with high populations, dense forests or steep slopes.

They combined the resulting map of China's wind energy potential with estimates of how expensive wind energy would be in different locations throughout the country.

There is well more than enough wind to provide all of China's electricity needs, the researchers found. Earlier this year, they reported that wind could provide 18 times more energy than the 2005 demand.

By incorporating economic information in the new study, the group found that the 2030 electricity demand could be provided at a price of 0.516 yuan (7.6 U.S. cents) per kilowatt-hour of electricity.

"The price of 0.516 RMB per kilowatt-hour falls into the range of prices in existing wind projects in China," study co-author Xi Lu of Harvard told Discovery News.

Developers of Chinese wind projects are guaranteed a price for power for an initial period -- typically about 10 years -- by the provincial governments as part of an up-front bidding process.

The team also calculated how much wind could be supplied at a price comparable to the price of coal-generated power, 0.4 RMB per kilowatt-hour. Even at this price, China could supply 23 percent of its 2030 electricity needs with wind, reducing its CO2 emissions by nearly 10 percent, about 2 percent of today's global total.

Meeting the 2030 demand with wind power would not blanket the whole nation with windmills, Lu added. "It is estimated that wind farms only take up land areas of 0.5 million square kilometers (193,000 square miles), which is only three quarters the area of the state of Texas."

What's more, the turbines themselves only occupy about 2 percent of the land they stand on. "The lands do not necessarily lose their original functions, such as agricultural fields or pastures," he said.

The estimates fail to include some important factors, said Liming Qiao of the Global Wind Energy Council, a trade association for the global wind industry.

"The model that (the authors) established is a little bit too simple to reach the conclusion that (they) made," he said. For instance, problems with wind turbine performance and with incorporating so much new wind power into the grid would remain, he said.

The authors agree that changes to the grid would be costly. But while the expense would be large, it is not unreasonable, they write in the new paper, given how much new energy generation capacity and grid improvement will be needed to accommodate the projected growth in demand for power in China -- renewable or not.