China Longyuan Electric Power Group, the country's biggest wind power producer, is close to launching its long-planned share sale in Hong Kong, and the company is aiming to raise as much as HK$5 billion, people familiar with the situation said.

Longyuan, which accounts for over a quarter of the country's wind-power capacity, plans to complete the initial public offer (IPO) within this year.

"The IPO preparation is now in the final stages," one person who has direct knowledge of the matter said.