Many large companies have been trying to reduce the power that their IT operations use, particularly in the data centre, where they can make significant savings.
It's harder for companies to reduce the power used by PCs spread around the company, but individual users can make an important contribution.
A lot of power is wasted by PCs left on when they're not being used. Too often they're not even switched off at night or over the weekend. This leads to a potential waste of up to 7,000kWh of electricity a year on just one PC, costing around £700 and equivalent to 3,812kg CO2.