BEIJING, July 15 -- Ten thermal power plants across China have been fined for dodging supervision on sulphur emissions, according to the National Development and Reform Commission (NDRC) on Tuesday.

Penalties totaling 519 million yuan (84.4 million U.S. dollars) were handed down after investigations into the operation of sulfur-removal devices in coal-fired plants.

Price and environmental protection authorities found that some thermal plants deliberately shut down their sulfur-removal device to reduce costs or avoid pollution monitoring.

To try to bring air pollution under control, China encourages coal-fired power generators to install devices to remove sulfur and other pollutants. Plants equipped with such devices receive government subsidies and are allowed to sell their electricity at higher prices.

Among those punished, Yangcheng International Power Generation, a Shanxi-based Sino-U.S. joint venture, face subsidy cuts or fines of 125.6 million yuan.