The release of a new central heating plan has shown that "low carbon" remains a government priority at a recent energy-saving conference.

The 2020 plan was promoted at the 2010 Beijing International Energy Saving and Environmental Protection Exhibition, held from June 12 to June 16 at the Beijing Exhibition Center. The theme this year was "low-carbon technology, green economy".

Cryptically titled as the "1+4+N+X central heating pattern" by Beijing Heating Power Group Co Ltd, it essentially plans to reform the existing network and centralize the city's boilers.

The formula might appear random, but the idea is straightforward. The heating company aims to have a central heating supply network (1), four large-scale gas-fired power plants (4), several medium-scale gas-fired cogeneration plants (N) to provide heating to around 10 million sq m of residential housing, and numerous other boiler rooms (X).

"The existing supply network mainly depends on coal power," said Gao Xinyu, head of the Energy Resource Department at the Beijing Municipal Commission of Development and Reform.

"The next central heating system will be mainly driven by gas, which is much cleaner and more powerful," he said.

Beijing is also in the middle of a network reform project to counter pipe leakage, corrosion and ageing, according to experts at the exhibition. At present, 498 residential communities have been reformed by the project, which is jointly funded by city-level and district-level governments.

The heating company said Beijing has built 19 large-scale coal-fired central heating centers to replace former decentralized and polluting boilers in outer suburbs and counties. It claims they have increased energy efficiency by 20 percent. It still plans to build another 11 plants this year in those areas.

"Centralizing the power centers will decrease the amount of waste significantly and provide better heating to residents," Gao said.

Energy-saving homes were the other issue raised at the exhibition.

According to a demonstration on heat supply metering, 96.3 million sq m of housing still does not meet energy-saving standards. Built before April 1988, they comprise 25.9 percent of residences in Beijing.

The homes that can be classed as "energy-saving" can be categorized into three generations: Those designed after April 1988 (17.4 percent), after January 1998 (33.5 percent) and after July 2004 (23.2 percent).

"By using new technology such as double-glazing, energy can be used more efficiently," Gao said, when questioned on how a home can be classed as "energy-saving".

Compared with the homes built before April 1988, the most recent design is believed to be 65 percent more energy-efficient.