China will tighten emission standards for thermal power plants, a main source of pollution, aiming to curb worsening environmental degradation. The Ministry of Environmental Protection said in a report on its website that emissions allowances for sulphur dioxide, nitrogen oxide and soot for thermal power plants would be reduced, while mercury discharges from coal burning and emissions from gas-fired boilers would also be restricted for the first time.

Beijing will also toughen emissions levels in environmentally-sensitive regions.

The new standards, which will take effect from January 1, 2012, may involve about 260 billion yuan ($40.74 billion) in new investments for power companies by 2015 to meet several key requirements.

China had 707 gigawatts of thermal power generating capacity at the end of 2010, accounting for 73 percent of overall power generating capacity. A majority of the plants use coal as fuel and half of China's coal output is used for power generation. ($1 = 6.382 yuan)