Nationwide wind power generation spiked 33.6% on the year in January to 2.16 million MWh, the number-one Chinese wind owner said in a filing to the Hong Kong Stock Exchange.

Curtailment, which has bedevilled the country's wind sector in recent years, likely kept as much as 11GW of turbines in China from producing full power in 2013, costing operators roughly $1.6bn in lost revenue. But the production uptick suggests things may be improving.

“Longyuan only expanded its capacity by about 20%,” Macquarie Securities analyst Patrick Dai told Recharge. “So actual electricity growth is coming from further improvements of utilization hours in January.”

In northeastern Heilongjiang province, generation fell 9.8% to 206,791 MWh. In adjacent Jilin province, wind-power generation plunged 15.6% to 25,358 MWh.

However, generation rose 38.3% to 535,996 MWh in the Inner Mongolia region, and jumped 41.4% to 150,695 MWh in western China’s Xinjiang region.

Longyuan's nationwide coal-power generation fell 12.90% on the year in January.

Longyuan has more than 10.6GW of wind in service.