People leaving computers on on standby is costing British industry £123.2m a year in energy bills, it has emerged. More than a third of office employees still fail to turn off their computers when not in the office. The so called "standby culture" may be responsible for one million tons of carbon being pumped into the atmosphere each year.

Home computers waste £41m a year and emit 220,000 tons of carbon dioxide when left on standby.

A nationwide campaign to reduce greenhouse gas levels begins today, with the focus on encouraging people to switch off electrical equipment, rather than just leaving it on standby.