Carbon trade key for cleanup

The largest carbon producer in the world, China is fighting to boost green growth through carbon trading markets, an industry expert said.

"The enigma of carbon trading not only lies in the fluctuations of stocks or economic gains, but also the impact on energy conservation, technology innovation and environmentally friendly industries," said Du Shaozhong, chairman of the Beijing Environment Exchange.

Under the trading system, companies are given carbon credits, or quotas. The bigger polluters have to bear the added cost of buying more credits, while less polluting companies can make profits by selling their credits.