On Mar 29, 12:46*pm, MahFL wrote:
Except all the PC's left on 24 hrs a day, using electricity produced
by coal/oil fired power stations....cough cough splutter.......

Unnecessary artificial lighting during the daytime must make quite a
big difference. Granted, the interiors of some buildings do need it as
they don't get much light, but others don't; even on this very gloomy
day, I've not needed to put the light on since I got up some 11 hours
ago.

Nick