Businesses can do much more to save energy through switching off light and electronic equipment, according to Environmental Data Services (ENDS).
The body, which is a leading provider of environmental intelligence for businesses, has also stated that many offices do not have the most efficient models of computers and do not run them in the most efficient way either.
Editor of the ENDS Report, Nicholas Schoon, said: "It's very significant given that we're not an industrial economy any more, we have a service economy and that's how we get our wealth these days, sitting in offices looking at screens all day, and as a nation that uses up a hell of a lot of energy.
"It will only change if people care about it, and if people who run offices care about it enough to put pressure on people to do their bit."
Research by Canon recently found that office equipment left on standby over ten days wastes enough electricity to roast 4.4 million turkeys at Christmas this year.
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