State-owned China National Offshore Oil Corp (CNOOC) is shutting down part of its renewable energy business, a company source said, as it looks to sell its wind and biofuels projects and shift its focus to coal-to-gas.

The company’s subsidiary CNOOC New Energy Investment has struggled to make profits after its 2007 start, and will see many activities shuttered, the source, who spoke on condition of anonymity, told Reuters.

CNOOC Group did not immediately respond to a request for comment.

The company has 10 wind power plants operational or under construction, with generation reaching 67 gigawatt hours per year, according to its website. Six of the wind farms, with a combined capacity to cut carbon dioxide emissions by 500,000 tonnes a year, are eligible to generate carbon credits that under the UN Kyoto Protocol can be sold to governments and companies in developed countries.

But insufficient subsidy levels for wind projects and rock bottom prices in the international carbon market have meant CNOOC has struggled to make a profit, the source said.

He also said CNOOC’s forays into the biofuels market, which has included trial production of biofuel from waste cooking oil, will end. The news came just days after the State Council, China’s Cabinet, said it would offer further support to its ailing solar power industry. China has become the world’s biggest wind energy producer, reaching 76 gigawatts of installed capacity in 2012, more than a quarter of the global total. The government’s target is to increase capacity to 100 MW by 2015 and 200 MW by 2020.

Zhang Ping, president of China Renewable Energy Industry Association, told the Global Times Sunday that CNOOC is closing its new energy unit because the firm focused on developing wind power, which is not well developed in China.

“China’s northern regions have abundant wind energy, but they lack upgraded power grids and strong market demand. Wind power cannot be fully absorbed,” he said.