At night, when demand is lower, these power stations can be switched off, which means that each unitofelectricity has a lower carbon footprint.
到了晚上，需求降低，这些发电站就会关闭。这意味着产生每单位电能所带来的碳足迹降低了。
2
An air-conditioning unit outside the house or building runs USES electricity to cool the air and then sends into the building through openings in the rooms of the buildings.
室外的一个空调装置则使用电力将空气的温度下降，下降的空气通过房间的通道送往整栋大楼。
3
Jug kettles are fast and convenient, but their fuel - electricity from the national grid - produces almost three times more greenhouse gas for each unitof heat than burning gas in the home does.