The bill's author, Rep. Michael Rogers (R-Mich.), said he hopes the study will help promote the use of energy-efficient servers and data centers through regulations that encourage conservation by federal agencies and offer tax incentives to private companies. The bill, which is co-sponsored by Rep. Anna G. Eshoo (D-Calif.), now goes to the Senate.

Rogers also believes buyers would benefit from an energy-rating standard for servers. The Energy Star rating now widely used on appliances and some computer equipment "changed the dynamics of how we buy appliances over time," he said. "People were buying the most energy-efficient appliances they could buy -- so we saw a model like that work."

Rogers' bill also asks the EPA to devise potential incentives and voluntary programs "that could be used to advance the adoption of energy-efficient data centers and computing."

Power consumption and cooling has been a top issue for data center managers because of the ever-increasing growth in server deployments. The U.S. server market is expected to grow from 2.8 million units in 2005 to 4.9 million units in 2009, according to data that tech industry groups sent to Rogers this month in support of the bill.

But data center mangers say business needs will play the bigger role in buying servers.