SHARES in Hanergy Thin Film Power Group fell as much as 9 percent Friday, a day after the Hong Kong bourse asked the mainland company about a stock price surge that transformed it into the world’s most valuable renewable energy firm.

    Hanergy shares, which closed down 6.85 percent Friday, have risen 137 percent since Jan. 23, giving the company founded by the mainland’s richest man Li Hejun a market capitalization of US$40 billion.

    The gain has outstripped the average 13 percent rise in the TRBC index that tracks Chinese renewable energy equipment and services stocks on Thomson Reuters, and also beat the Hong Kong benchmark index’s 2.4 percent drop in the same period.

    In a statement to the Hong Kong stock exchange Thursday, Hanergy said it was not aware of any reasons for the unusual price and trading volume movements.

    The stock was the most heavily traded Thursday via the stock connect program that allows mainland investors to trade Hong Kong shares, with shares worth more than HK$800 million (US$103 million) changing hands. This accounted for more than half of the total turnover of Hong Kong stocks bought by mainland investors.

    Hanergy was also one of the top 10 traded stocks via the link for the past month.

    Some traders attributed the spikes in price and trading volume to a “short squeeze,” where a heavily shorted stock unexpectedly jumps in value sparked by an increase in buying.

    Hanergy said Tuesday it expects 2014 net profit to have increased by more than 55 percent due to a “significant increase in revenue.”

    The company’s valuation Thursday ranked it above Denmark-based wind power company Vestas Wind Systems A/s and U.S.-based solar module manufacturer First Solar Inc., the second and third most valuable companies on the TR Global Renewables index.

    (SD-Agencies)