In addition, a cross-agency data center consolidation task force, created in February, is looking at ways to better measure the costs of data centers, Baer said.

Many government data centers that came online in recent years may have been based on projections that didn't take into account relatively new technologies like virtualization, Weber said. Given a multiyear funding cycle for large IT projects, it's no surprise that the government has too many data centers, he said.

"They made the best guess they could," he added.

The MeriTalk survey shows that more information is needed as OMB moves to close data centers, said Senator Tom Carper, a Delaware Democrat and chairman of a Senate subcommittee focused on government IT spending.

The survey is a "bright warning light for those of us interested in closing and consolidating wasteful and duplicative data centers," Carper said in a statement. "There's also little knowledge about how much -- and how efficiently -- federal data centers are using energy. While we are trying to cut the fat from our data center budgets, it seems we can't even see over our belts to the number on the scale."