Is this a record? I photographed this outside light as an example of bad practice at Newent Community School in 1986 when I was Gloucestershire’s energy manager. I go past it every week on my way to the sports hall and in 30 years it has never been off during daylight hours. They’ve replaced the doors, windows and roof, and some trees have grown up between it and their new eco lab, whose roof-mounted wind turbine is just sufficient (on those rare occasions that it can be seen turning) to power the light above the door on the neighbouring science block:

Let’s be realistic: unnecessary lighting doesn’t waste much electricity. But unfortunately it is the most visible indicator of one’s commitment. It’s no good feeding children piffle about sustainability if you demonstrate a disregard for proper management of energy.