IN a vast prairie north of Hohhot, capital of north China's Inner Mongolia Autonomous Region, hundreds of wind turbines stand like a vast, unbroken forest.

The turbines have created both opportunities and problems for the region's power companies.

"I long for wind, but I also fear the wind," says Su Changyou, a manager of a wind farm in Siziwang Banner (County). "During high winds, my wind turbines will rotate in full gear, which means higher profits. But sometimes, my telephone rings with calls from power grid controllers ordering us to limit our power generation."

Since Su's wind farm was connected to China's power grid last May, only about 60 percent of the farm's turbines have been in operation. The rest of the turbines must remain idle to avoid overloading the grid.

Qi Laisheng, general manager of the Inner Mongolia subsidiary of Longyuan Power, China's largest wind farm operator, says "these things happen all the time here. About a quarter of the turbines on my wind farm have to remain idle, even on the windiest days."

Grid access has become a nightmare for Inner Mongolia's burgeoning wind power industry. Wind farms in the region have a total installed power capacity of 6.5 gigawatts (GW), the most of any region in China.

China surpassed the United States to become the world's largest producer of wind power at the end of 2010. However, China's wind power industry has been troubled with growing pains.

Under China's Renewable Energy Law, which was created in 2005 and amended in 2009, wind farms that are connected to the country's power grid must be constructed with prior approval from the government.

The State Grid Corporation of China (State Grid) and the Inner Mongolia Grid, an independent provincial power grid, have ensured that all of the wind turbines connected to their power grids are government-approved. However, they cannot allow all of these turbines to operate simultaneously.

One reason for this is the fluctuating nature of wind power. Some industry officials believe that wind power may pose a serious threat to power grid stability, saying that wind power should account for less than 5 to 10 percent of any given power grid's total power. However, on April 8, 2010, wind power accounted for 18.7 percent of the Inner Mongolia Grid's total power without any negative repercussions.

A great deal of wind power is wasted during the winter season, when thermal power generators are used to supply heat for most of Inner Mongolia's residents. The Inner Mongolia Grid prefers to use thermal power generators because they can generate electric power while simultaneously creating steam, which can be used to heat homes and businesses in the region.

Tao Ming, director of the Siziwang Banner wind power office, says that "during the winter, the grid gives priority to generating power with thermal power generators. Inner Mongolia has relatively low demands for electric power because of its underdeveloped industries. Thermal power plants can work at full steam, while wind turbines have to remain idle."

The Inner Mongolia Electricity Council says wind farms connected to the Inner Mongolia Grid lost several billion yuan in 2010 because of idle turbines. According to a February report by the China Electricity Council (CEC), about one-third of China's wind turbines are idle, a sign that China's wind power industry has some serious problems to solve.

"The grid is like a giant jar, and wind power is like a river," says Lu Jianjun, director of the wind power office of Inner Mongolia's Chayou Central Banner. "The Inner Mongolia grid 'jar' is full, but the wind power 'water' keeps flowing in. We have to cut off the 'river'."

Power shortages

However, the economic powerhouses of central and eastern China are in need of surplus power. These regions have faced power shortages this year, with more projected to follow in the coming months.

Wang Zhixuan, secretary general of the CEC, says that China's central and eastern regions need at least 30 GW in additional power to operate smoothly. At the same time, 26 GW of installed power capacity in China's northern regions have been idle, most of it generated by wind turbines.

Wang Bingjun, director of the Inner Mongolia Energy Bureau, says, "The Inner Mongolia Grid has reached its upper limit in accepting wind power for local consumption. The only solution is to send out wind power over long distances and integrate it into the much larger State Grid."

This, however, is easier said than done. Longyuan's Qi says, "This is hard to do because we do not yet have a concrete method of transmitting wind power."

According to the CEC's February report, China has yet to create a reliable, stable way of transmitting wind power outside of local grids, and also lacks support facilities for these grids.

Despite these problems, state-owned power companies are continuing to build new wind farms. Their zeal can be partially attributed to the government's requirement that power companies must use non-hydropower renewable energy sources to generate at least 8 percent of their power by 2020.

This requirement is part of the government's pledge to cut down on carbon dioxide emissions. Wind power is believed to be the cheapest and most efficient renewable power sources available to these companies.To solve power transmission problems, the State Grid has invested 41.8 billion yuan (US$6.53 billion) to construct 23,200 kilometers of transmission lines. However, even this amount will be far from enough.

Better option

Shi Lishan, the deputy director of the new energy and renewable energy department of the National Energy Bureau (NEB), thinks there might be a better option. Shi says that China should build wind farms in areas with lower average wind speeds, as opposed to expanding existing wind power farms and transmitting power over great distances.

The China Wind Energy Association (CWEA) says that about 68 percent of the country's viable wind power-generating regions qualify as low wind speed areas. China's wind power industry is mainly concentrated in its northern and southeastern regions, where wind speeds are typically quite high.

Bai Jianhua, director of the State Grid energy strategy and planning research institute, says China will expand its installed wind power capacity in low wind speed areas to 20 GW, or about 20 percent of the country's installed wind power capacity, by the end of 2015.

China has made a substantial step in this regard. Longyuan completed constructing a 200MW low-speed wind farm in Lai'an, Chuzhou City of central Anhui Province, on May 10. It is expected to generate 390 million kWh electricity per year.

Longyuan says the wind farm may run for nearly 2,000 hours a year, compared with 2,600-2,800 hours in the northern areas. But Lai'an sits near the terminal users of the East China Grid, which will ensure wind turbines run at full capacity. China has many similar areas like Lai'an that are based in Anhui, Hubei, Fujian and Yunnan provinces, all big users of electric power.