China's environmental watchdog on Monday expanded a trial program on subsidizing denitrified power plants to the entire country to further cut nitric oxide emissions and protect the environment.

The program, previously available in 14 provinces, grants a subsidy of 0.008 yuan (0.00127 U.S. dollars) per kilowatt-hour for electricity generated by verified coal-fired power generation units with denitration facilities, according to a circular issued by the Ministry of Environmental Protection (MEP) and the National Development and Reform Commission (NDRC).

In the 12th Five-Year Program (2011-2015) for China's National Economy and Social Development, the country set a compulsory target of reducing the content of nitrogen oxide by 10 percent by 2015.

However, total nitric oxide emissions increased 5.73 percent in 2011, while the first drop was recorded in the first half of 2012, down 0.24 percent year on year.

The NDRC attributed the drop to the denitration-subsidy program and set the 2013 annual reduction target at 3 percent.

In addition, the MEP requested provincial environmental authorities finish examinations on each application to the program within 30 working days.

By the end of last year, China's total denitrified installed capacity stood at 225 million kw, which means the annual subsidy may top 10 billion yuan, according to the MEP.