Sino-US collaboration on clean energy technology will set a good example for other countries, US Commerce Assistant Secretary David Bohigian said Wednesday.

The two countries have much to gain by working together on knocking down trade barriers and working jointly in such fields as alternative energy, he said.

"If China and the United States are not working together, the problems will only get worse when it comes to air pollution, water pollution and climate change," Bohigian, whose job mainly concerns international economic policy, said.

The assistant secretary this week led the Second Clean-Energy Trade Mission to China. It consists of 17 US companies with advanced technology ranging from solar power to clean coal.

The continuing rapid growth of the Chinese economy presents unparalleled opportunities and challenges, he said. "US clean-energy companies can help China meet its enormous energy demands while deploying technology that benefits the environment."

The last trade mission, in April 2007, was the first clean energy trade mission that the US government had ever led, and yielded hundreds of millions of dollars worth of sales.

"Having our companies here on the second clean energy trade mission has helped our countries institutionalize the ability for our companies to get together.

"Another important step we've made today is opening up a dialogue on clean energy and energy efficiency, along with our partners at China Chamber of Commerce for Import and Export of Machinery and Electronic Products, the National Development and Reform Commission and the Ministry of Commerce," he said at yesterday's US-China Clean-Energy Dialogue.

"I really do expect that will continue in 2009 under a new president and beyond. Because it really has become a generational issue, that this generation of policy makers and more and more voters understand the importance of these issues."