Switching off idled computers, unused lighting and copy machines at night or on weekends might seem like a fairly small and relatively uncontroversial way to save energy — and reduce CO2.

But I nevertheless get grief at times for switching off idled computers or some of the overhead lights at night, when the office is all but empty. Only sometimes does it help when I try to explain to those who complain that it is a waste of energy and producing C02 that could easily be avoided — and tacitly hope the process might help create a new power-saving, CO2-reducing zealot like myself.

“It takes too long to reboot it in the morning,” is one common complaint. (For the record: it takes about 3 minutes).

“I can’t remember my password,” is another argument. (For the record: I don’t have an answer for that).

Some especially clever colleagues in the office where I work, which has about 100 computers, have managed to lock theirs at night to try to prevent me switching them off. It seems ironic that they would expend so much energy, so much (of their own brain)  power to deliberately waste energy. But I took up the challenge. I just pulled the plug. Maybe they’ll find a way to lock that too. But it’s not just where I work. In other offices I’ve visited the view seems to be the same — just leave the PC on. And you only have to walk down the street late at night to see some offices, presumably all but empty, ablaze with lighting.

I realise that, in a business where every second counts, three minutes to reboot in the morning might seem like half a lifetime — and no one would argue against leaving one idle computer on overnight to spare those vital seconds in case there is an urgent early morning task. But it all makes me wonder: if an office like mine filled with well-educated, well-informed people who could not possibly have missed the growing published evidence of global warming is seemingly unwilling or unprepared to make even a minor C02-saving adjustment like switching their computer off at night, what are the chances for change elsewhere?

It may only seem like a pittance to leave a PC or a light on at night. But I did some checking and found out that our office has an electricity bill of 30,000 euros per year — a surprising fact that usually helps end the arguments.  My company spends about 150,000 euros nationwide for its electricity – it seemed like a staggering amount to me for a company that is proud of having a small carbon footprint.  But I wonder: can’t that footprint be made even smaller — without pain?

Each PC left on overnight uses about 30 euro cents – 43 U.S. cents — of electricity per day.  It adds up fast to a lot of kilowatts and a lot of CO2.

It’s not hard to imagine the enormous amounts of power wasted and the tonnes of CO2 produced if those figures are multiplied by the number of offices around the
world. A survey last year by a German government environmental agency found that Germans waste 3.3 billion euros a year by leaving appliances on standby rather than switching them off, which one environmental group said meant that the annual output of two to three nuclear power plants goes for wasted power.