HONG KONG - Huaneng Renewables Corp, the wind-power unit of one of China's biggest electricity producers, plans to revive a Hong Kong initial share sale after cutting the size of the offering by about 20 percent to $1 billion, said two people with knowledge of the matter.

The unit of China Huaneng Group Corp aims to start trading in early June, said the people, who declined to be identified. Huaneng Renewables scrapped its earlier plan because of unexpected and excessive market volatility, the company said on Dec 13.

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Huaneng Renewables, aiming to boost capacity to meet rising Chinese demand, sought as much as $1.3 billion in the previous share sale attempt. The benchmark Hang Seng Index completed its longest stretch of losses since April 2003 in the eight days to May 6 as economic reports in the United States and falling commodity prices dampened investor confidence in the global recovery.

Morgan Stanley, China International Capital Corp and Macquarie Group Ltd are managing the Huaneng Renewables sale, the two people said.

The government wants at least 15 percent of the country's energy to come from renewable sources, including wind, by 2020. China increased its windpower capacity in 2010 by 67 percent to 42.5 gigawatts, according to Bloomberg data.

China Datang Corp Renewable Power Co, the wind unit of the power producer China Datang Corp, raised HK$5 billion ($643 million) in a Hong Kong initial public offering in December. The shares have gained 4.6 percent since and were at HK$2.29 as of the noon break. The Hang Seng Index advanced 1.7 percent in the same period.

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