The UK's 200 largest publicly listed companies are wasting in excess of £61m annually by not maximising the energy efficiency of their desktop computers, research published today has claimed.

A study from IT services firm Computacenter and Fujitsu Siemens Computers (FSC) claims that the adoption of a 'greener' desktop strategy and better working practices could deliver significant financial savings and reduce the environmental burden.

The joint research investigated the energy consumption of 200 publicly listed companies based on the number of traditional desktops they operated daily, and calculated the potential energy savings that could be made if these were replaced with more energy efficient 'green' PCs.

The study suggests that companies should introduce policies and procedures that encourage employees to switch off their computers when not in use. For example, the IT department could use automated software that turns off all idle PCs out of office hours.

Previous research from FSC found that more than a third of workers do not switch off PCs when they leave the office.

The 200 companies were collectively found to be wasting in excess of £61m of electricity per annum, equating to over 2.8 million kilowatt hours of energy.

By adopting green IT equipment and switching off desktops the report estimates that the firms could make annual savings of around £305,000 each.

The report went on to claim that one of the largest companies in the UK top 200 has the potential to save at least £2m on its annual electricity bill by adopting green IT equipment and policies.

Ed Kenny, director of corporate hardware at Computacenter, said: "Our figures are conservative, as they are based on PCs running at idle. Therefore, energy consumption on a day-to-day basis is actually likely to be significantly higher.

"Although technology can help companies realise cost savings and operational efficiencies, it is important that these are not achieved at the expense of the environment."

Garry Owen, head of product marketing at FSC, added: "The fact that green PCs and the adoption of energy efficient practices will save money and reduce the damage done to the environment is a compelling business case for any organisation."