According to a report from the Environmental Protection Agency (EPA), U.S. corporations are moving toward virtualization at least in part due to concerns over their power consumption.

X86-based servers consumed 68 percent of the electricity used by IT equipment in data centers during 2006, but run at processor-utilization rates of between 5 and 15 percent, according to the EPA's report on the efficiency of corporate data centers.

It may not be the only reason, but two companies that have been able to increase their utilization, cut power consumption and save money on both hardware and support, say worries about electricity did help move them into the virtual world.

BancMidwest Services, a subsidiary of Mainstreet Bank in St. Paul, Minn., used VMware ESX Server to consolidate three servers into one, according to BancMidwest IT manager Brian Priebe. The server is connected to a Compellent Storage Center storage area network (SAN), which stores the virtual machine images for the host computers.

"To take in server virtualization on our side, we are able to expand our data center without expanding the physical footprint of the data center, which is key for a small business," says Priebe. "We're not increasing our power and cooling costs."

Priebe says he'll probably virtualize and eliminate another five to six physical servers and save both the floor space and electrical consumption they take. Priebe is able to quantify his energy consumption with the use of tools from Compellent that monitor the virtualized servers.

"We were able to separate all our applications and bring them into their own VMs," says Priebe. "We were then able to monitor the virtualized servers with our Compellent chargeback and storage resource management tools and look at and associate what the cost of a virtual machine was, how much disk space it was taking up, and then charge back its use to the appropriate organization."

"As we take on those applications we can say no more power costs, no more cooling costs—we use the term 'reduce, re-use and re-silo'—reduce the physical, re-use the servers for a test environment," says Priebe.

Power problems—the kind that turn the lights out unexpectedly, not power-use issues—drove Los Angeles-based Ares Management toward virtualization, says Ping Ooi, the investment company's associate VP of technology.

More to test the waters than migrate anything, Ares virtualized a Blackberry server in its Los Angeles office, and replicated it to New York. When the machine in LA went down "we brought up the server in New York and no one was the wiser," he says.