What is the energy cost of keeping a computer cool?

Paul - It all depends on the air-conditioning system you've got, but in Cambridge, our power costs are 25% of our total running costs which in this case is about Ã?,£250,000 a year. The cooling is 1/3 of that power, so around Ã?,£80,000 pounds a year just to keep it cool. Dave - I guess if you're just dealing with an individual laptop, then their cooling is going to be far, far less than that [as a proportion] because it's just running a small fan. Paul - In a laptop, you can just cool passively to air whilst we have to actively take the heat away.