BEIJING, May 23 -- When one side of the earth is lit by the sun, the other side is in dark. This highlights the importance of joint efforts in developing solar energy.

But worldwide efforts have often met challenges, as in the latest anti-dumping and anti-subsidy investigations launched by the United States against China's photovoltaic (PV) products.

China's PV industry issued a statement on Wednesday, opposing the second investigation in three years by the United States, several days ahead of the release of the U.S. preliminary investigation results.

The United States initiated the investigations in February, the second after a similar one in 2011, which slowed the Chinese PV industry and damaged the development of the U.S. PV application market.

This time, the preliminary anti-subsidy investigation result is expected on June 2 and the preliminary anti-dumping investigation findings on July 28.

A large amount of hard evidence presented by the Chinese companies during the last investigation has already proved that there are no such things as dumping or illegal subsidies.

Chinese PV products win the affection of the world based on superior quality, reasonable prices and good after sales services, rather than taking advantage of any government subsidies.

It is a great pity the evidence was ignored by the U.S. side.

The protectionism measures of the U.S. side will not only hurt Chinese exporters, but also domestic market players and American people due to higher prices they would have to pay.

If the punitive duties were imposed, large PV power plants in the United States would be devastated by soaring costs and the nationwide application of clean energy would lose momentum for further expansion, which will in turn drag down economic growth and employment.

That is why the U.S. Solar Energy Industries Association have expressed opposition to the trade conflict.

As China's PV exports to the United States and EU declined over the past years, its shipments to Japan and emerging markets like India and South Africa rose. Asian buyers absorbed more than half of China's exports in the first quarter, as compared to less than 20 percent for the EU market.

This in a way indicates that many more countries have become interested in the clean energy source as its cost declines steadily.

As the world PV production center shifts to Asian countries like China, the worldwide process of technology transfer and clean energy development is accelerated. This is important to the overall development of the global PV sector.

China and the United States should seek proper settlements of trade disputes with full consideration of the mutually beneficial situation for PV industry growth.

Negotiation is the best resort to bridge the difference and create a win-win situation, as proven by the successful settlement of a similar case between China and the EU a year ago.

A tit-for-tat approach always hurts. The two sides should endeavor to exclude this option from their arsenals with views to create a favorable situation for global growth.