The European Union launched an anti-dumping investigation into imports of solar glass from China on Thursday, a move seen by industry observers as a way to pressure China amid a long-running dispute over solar panel technology.

The European Commission said on its website that the investigation is based on a complaint lodged by EU ProSun Glass, an association representing European solar glass manufacturers, which claims that solar glass from China is being dumped in the EU at prices below market value and causing material injury to the EU solar glass industry.

"Trade protectionism is bad for both sides," said Meng Xian'gan, deputy director of the China Renewable Energy Society. "It is really wrong to escalate the trade disputes. However, if the EU continues to pressure China, we have to take action to protect our trading rights."

In September, the EU started an anti-dumping investigation into Chinese solar panel products, following the United States, which had imposed punitive tariffs of up to 250 percent on imported Chinese solar panel products.

According to the EC's statement, the solar glass case is a stand-alone investigation concerning a clearly distinct product and has no direct relation with the previous investigations into Chinese solar panel products.

The investigation will take up to 15 months, although under trade defense rules the EU could impose provisional anti-dumping duties within nine months if necessary.

In addition, the commission said it had not received any anti-subsidy complaints on China's solar glass so far.

Solar glass is special glass used mainly to make solar panels. It is an essential component not only of solar panels, but of many other solar energy products.

According to the EC, the EU's solar glass market is worth less than 200 million euros ($262 million).

China's solar panel manufacturing industry had been developing rapidly in the past few years before the anti-dumping and anti-subsidy probes were launched by the US.

From 2006 to 2009, the solar glass industry saw an annual growth rate of about 40 to 60 percent.

In 2008, China's solar glass annual production capacity reached about 486,000 metric tons with 24 production lines, with the country becoming the largest producer of solar glass in the world.

"As the Chinese government continues to make efforts to expand the domestic market for photovoltaic solar products and to encourage distributed solar generation projects, domestic demand for solar glass will grow," said Meng. "In fact, the country's solar glass output currently cannot meet the domestic demand."

Last year, China's solar panel output reached about 23 gigawatts, a 2 gW increase compared with the previous year, according to Meng.

"Although China doubled its solar panel output in 2011 compared with 2010, the increase last year amid the background of the trade disputes, which severely affected the country's exports, has shown the potential of the industry in China," he said.

The Ministry of Commerce said it deeply regrets the EU's decision to start the probe into China's solar panel products.

The solar glass investigation was launched based on political considerations rather than pure trade disputes, said Meng.

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