Recommended use of timing sockets. [Photo by Sun Ye/China Daily]

She now turns off the lights whenever she leaves a room, unplugs appliances whenever she finishes using them and separates the wet from the dry almost automatically when dumping garbage.

"You start to find so many small things you can do to help," says Luo. "It would be natural for anybody."

Wang Yuan, the project manager with FoN says: "It's not our goal to seek a specific cutting of emissions.

"What we hope to achieve through all these things is to encourage and spread the word about doing the little things you can to save the environment."

That said, families who refurbished their homes the energy-efficient way saw spectacular results.

Wang's team found that each participating household saved between 30 and 50 percent of energy on average after retrofitting, and none of them had sacrificed their quality of life for it.

"We can only see part of the after-effects like lower electricity and gas bills," says Wang.

"That's money saved. But there are also benefits one can't gauge with a barometer."

Beijing, a city which is perennially dry, becomes even more testing when heating comes on in the winter. Heating in the city mainly runs on gas now, but part of it still uses coal.