This is what it sounds like when the other shoe drops. Last year SolarWorld Americas and the Coalition for American Solar Manufacturing (CASM) launched a campaign against China’s silicon-based photovoltaics trading practices. That’s resulted in two preliminary Commerce Department rulings imposing tariffs on imports of Chinese-made silicon photovoltaics, some higher than 200 percent. Yesterday (July 19) China’s Ministry of Finance (MOFCOM) announced that it is launching its own investigation into U.S. polysilicon trade practices.

The ministry is now investing whether suppliers of solar-grade policysilicon from the U.S. and from South Korea also engaged in unfair trade practice with China. The investigation is scheduled to last a year,  According to Bloomberg.

The Coalition for Affordable Solar Energy (CASE), a coalition of solar manufacturers, suppliers and solar installers has opposed SolarWorld and CASM’s actions from the start. “This does no one any goodness it’s hurtful,” said Ed Rothschild, a spokesperson for CASE.

He contended that Chinese policy has allowed the country make less expensive PV modules. “The Chinese have an industrial policy and we don’t. If we don’t that’s our fault,” he said.

Now, U.S. polysilicon makers that export to China are concerned about the action. Among them, Dow Corning and Hemlock Semiconductor and REC Silicon. In a press statement Dow President Robert Hansen said, “This case proves that no country or industry wins when trade disputes escalate. In China, these actions threaten the Chinese solar industry’s access to the critical technical collaboration and material supply companies like Hemlock Semiconductor currently provide Chinese solar cell and module producers.”

While SolarWorld Americas, whose parent is the German SolarWorld has pursued the case, it doesn’t mean the company is necessarily benefitting from the action. “SolarWorld’s stock has gone down by 70 percent and the CEO just announced he’s not taking a salary or bonus until they [recover],” Rothschild said.

CASE contends that the competition in the solar industry has driven the costs of solar down and argues to allow the market to work. “It’s a tough, competitive world out there. Cost keeps going down,” Rothschild said. “You meet the cost numbers or you’re not going to make it,” he said.