US President George Bush has signed legislation directing the US Environmental Protection Agency (EPA) to study energy use in data centres.

Bush Wednesday signed the bill, passed by the Senate 8 December, which authorises the EPA to analyse the growth of energy consumption at data centres. The issue is a growing concern to companies that operate large groups of servers, storage devices and other computer equipment. Many data centre operators find that the cost of electricity and of the air conditioning that keeps servers cool rivals the cost of the servers themselves.

The EPA study should help to promote more energy efficient solutions across the high-technology industry, said Steve Kester, manager of the government relations division of chipmaker Advanced Micro Devices (AMD) and one of several high technology companies endorsing the bill.

"We're very pleased that the [Bush] administration sees this as important," Kester said. The EPA study is expected to take about six months to complete and could result in the agency establishing measurements to judge the energy efficiency of servers, processors and other data centre equipment.

AMD hosted a forum 6 December at its headquarters in California, with the US Department of Energy (DOE) and representatives of major technology firms, including Dell, HP, IBM, Sun Microsystems and Intel. The DOE's office of Energy Efficiency and Renewable Energy called the gathering a "tech industry working group" to exchange ideas on energy conservation.