Chai noted that another obstacle to energy-saving is that cutting energy consumption would become more and more difficult as the process deepens. The outcome could take some time: While it costs only 100 yuan to cut the initial 10 percent of energy consumption, it could cost as much as 150 yuan to cut another 10 percent.

This is why the central government lowered the per-GDP energy consumption target to a 16 percent reduction from a 20 percent reduction during the 11th Five-year Plan (2006-10).

But some experts said local governments' ignorance has also played a role. Though the local governments have paid lip service to the importance of energy and emission reductions, while, in reality, GDP growth is always considered above environmental concerns.

This is not only because local governments have little incentive in curbing emissions, but curbing emissions often come at the expense of GDP and local fiscal revenue. It is also because a failure to realize energy targets does not invite severe punishment, while failure to realize GDP targets does.

Chai said rather than rewarding efforts such as installing energy-saving and emission-filtering facilities, it is wiser to reward results, such as the recent 50 billion yuan program to reward provinces that have actually shown progress in curbing pollutants emission. Of course, that would demand an accurate assessment system.

Experts also said that to really implement the target, provincial-level governments have to overcome the difficulties in breaking down the target into sub-provincial and county levels and coordinate their interests.

"In practice, it will be very difficult to distribute the target fairly. For example, a county in Henan province uses a huge amount of coal because a major State-owned power plant is located there," said Xiao Xuanwei, a researcher with the Development Research Center, under the State Council. "In theory it should share a corresponding energy reduction responsibility. But it may argue that it only consumes a small share of the electricity and a majority is used by other regions."