Opened in 1999, Huaneng Beijing Thermal Power Plant has four coal-fired generation units, which have a combined capacity of 845 megawatts. It provides 10 percent of the electricity consumed in Beijing annually and about 33 percent of the heat supplied to the city's central heating pipe network.

In 2006, when Beijing was applying to host the 2008 Olympic Games, the plant upgraded the desulfurization devices in four boilers, lowering sulfer dioxide emissions from between 400 to 500 milligrams per cubic meter to less than 50 mg. A year later, it modified denitration devices, technology that removes nitrogen oxide from exhaust gases, and reduced nitrogen oxide emissions from 400 mg per cu m to less than 100 mg.

In recent years, PM2.5 levels have become a matter of public concern. As a result, this year, Huaneng Beijing has finished upgrading one of its dust-collection facilities by using a technology currently employed in Japanese coal-fired power plants, which lowered emissions of dust to less than 10 mg per cu m.

While Beijing plans to cut its coal consumption to 15 million metric tons in 2015 from 23.3 million tons in 2012, the power plant has also made its own plans for the adoption of clean-coal technologies, setting a target of reducing sulfur dioxide emissions to 20 mg or less per cu m and nitrogen oxide emissions to less than 30 mg.

"Through technical transformations, our coal-fired power units can reach the same level of nitrogen dioxide emissions as gas-fired ones," said Du Chengzhang, vice-president of Huaneng Beijing.

In 2010, in response to government requests, the plant began building two gas-fired power units. Eighteen months later, it completed a 168-hour test of the units. However, as the company has not yet fully mastered the core technologies used in gas-fired power units, it has to pay the supplier 0.04-0.05 yuan per kilowatt-hour to maintain the equipment.

If Beijing carries out a wide-ranging conversion from coal-fired to gas-fired power units, the generating costs and prices of electricity and heating will definitely rise. Du said he was hopeful the government would allow the plant to modify its coal-fired power units instead of replacing them with gas-fired ones. The plant can bear the cost of the technical transformation and will not require government subsidies, he said.

Unlike other State-owned thermal power plants in the capital, Beijing Huaneng's coal-fired power units use advanced filtering systems to lessen the environmental impact.

"The government should formulate different plans for different thermal power plants to reduce air pollution, rather than forcing all of them to adopt the same measures. If we were allowed to keep our coal-fired power units, it would benefit not only our company but also society as a whole, because it would help to keep prices low," said Du.

(China Daily USA 09/18/2013 page8)