Asia has driven the sector’s continuing growth, with China adding 7.8 GW to hit almost 34 GW by the middle of the year. The United States still leads in overall capacity but gained only 1.2 GW – and is set to be overtaken by China by the year-end.

Global capacity, which totalled 159 GW at the end of last year, is set to gain between 35 and 40 GW this year, said the World Wind Energy Association. The market slowed slightly in the first half compared to the same period of 2009. New capacity for all of 2009 totalled 38 GW.

“The wind industry around the world has become a major player on the energy markets,” said Stefan Gsänger, WWEA’s secretary general.

“However, the slowdown in some countries is demonstrating that the success of wind power is not yet guaranteed automatically.”

In his view, legislative changes such as smoother building permission process and more extensive feed-in tariffs that cover access to grids are urgently required.

“In order to keep high social acceptance, special political consideration has to be given to models that involve local citizens,” he said.

“Furthermore, in order to bypass financing problems in developing countries, new international policies such as a global feed-in tariff programme should be adopted. We urge the governments to take such groundbreaking decisions during the UN Climate Conference in Cancún in December.”