The U.S. Trade Representative’s office is sharpening the focus of its probe into China’s policies supporting renewable energy. USTR Ron Kirk is targeting China’s Special Fund for Wind Power Manufacturing. He has asked for talks with China about that fund under World Trade Organization dispute-resolution provisions.

In announcing the move on Dec. 22, the USTR office said China seems to be providing subsidies that are barred by WTO regulations. The agency says grants awarded by the wind-power fund appear to be conditioned on Chinese manufacturers in that sector using Chinese-made parts.

USTR estimates the fund’s grants awarded since 2008 could amount to several hundred-million dollars, with grants now available that range from $6.7 million to $22.5 million. Kirk said, “These subsidies effectively operate as a barrier to U.S. exports to China.”

In a Dec. 23 statement, China’s Ministry of Commerce expressed “grave concern” about USTR’s request and said its wind measures “comply with WTO rules.”

USTR launched its investigation of China’s “green” technology policies on Oct. 15 in response to a petition from the United Steelworkers (USW) union.

While seeking talks on China’s wind-power fund, USTR also says it has made progress on other issues raised by the USW. The agency says that, during meetings of the U.S.-China Joint Commission on Commerce and Trade on Dec. 14-15, China agreed to change the criteria it uses to approve wind-power projects. It no longer will mandate that foreign companies have experience supplying equipment for major Chinese wind projects but will recognize such experience elsewhere, according to USTR.

USTR also says two other subsidy programs the USW cited in its filing, the Export Research and Development Fund and the Ride the Wind program, have been halted.

The union and congressional Democrats praised USTR’s action, but USW President Leo W. Gerard says the large, complex case will be a lengthy one.