Data centres are going to be more and more uncomfortable to work in as they get hotter and hotter, warns Gartner Group. High-density technologies, such as blade computers, have enabled firms to pack increasing amounts of computing power into small spaces.

The space required to house computers has shrunk in terms of processing power per square metre, but power requirements have increased along with the requirement for cooling. The number of server racks is increasing and reducing the amount of floor space per rack in data centres. Increasing use of cheaper x86 chip-based servers has presented problems for data centres which haven't been redesigned for over six year, according to Gartner.

While a stand-alone server in a rack used to use 2 kilowatts of electricity, a standard rack that is 50 to 80 per cent filled with blade servers consumes between 15 kilowatts and 30 kilowatts. Gartner predicts that within 12 to 18 months organizations will have to make major changes to accommodate the heating and cooling challenges.

Analyst Rakesh Kumar warned: "It will come down to a balance between the power, the cooling and the floor space. What that means is legacy data centres are obsolete." Gartner estimates that electricity costs could go from 10 per cent or less of IT budgets to 20 to 30 per cent if left unchecked.

The UK is heading towards energy shortages because of companies' burgeoning use of IT, according to new research yesterday that called on companies to overhaul their IT systems radically and install eco-friendly technology.

According to the Power and Cooling Survey 2006 from analyst firm BroadGroup, an average UK data-centre uses more power in a year than the city of Leicester. Such demand will severely test the operational viability of UK data centres by 2010.

The annual energy costs of an average UK data centre are estimated at about €5.3 million per year, according By 2010 this is expected to more than double to €11 million, making the UK the most expensive place in Europe to host a data centre.