The computing revolution comes with a not-often acknowledged environmental cost. Computers, as well as computer servers, use energy and give off heat. Then they have to be cooled down, using more energy.

At Vanderbilt University, officials with Information Technology Services are using a "server virtualization" strategy to dramatically reduce the rising energy demands caused by the computing needs of a large research university.

Through the sharing of servers maintained by ITS, various portions of campus including the math department and Owen Graduate School of Management are increasing the security of their data and helping the university lower energy costs and its environmental footprint.

It's carpooling for computers, and its impact at Vanderbilt is just beginning. It's a growing trend in the industry as demand for computer power continues to increase, and Vanderbilt is helping to lead the way among the university community.

 "There's a myth that everything on the Internet comes at no cost and gets better all the time," said Matthew Jett Hall, assistant vice chancellor for ITS at Vanderbilt. "The more physical servers we have, the more our power costs go up and the more our heat profile goes up. It's not very green."

With server virtualization, one physical server hosts several virtual machines. The result: fewer servers working harder, reducing heating and power costs. It also puts servers in a secure, highly-maintained environment less vulnerable to sabotage.

 In the past year, ITS officials estimate that Vanderbilt began saving 20,575 watts per hour because of server virtualization for 35 percent of the servers they manage. Efforts are underway to increase that to 50 percent soon, and 75 or 80 percent as time goes on. Departments who maintain their own servers, who may have security, facility, or power concerns, are encouraged to take advantage of the server virtualization service. For information from ITS on how to obtain this service, see http://its.vanderbilt.edu/vm.php.

 "Not everything is amenable to virtualization," Hall said. Some scientific applications that require attachment to a sensor or real-time data close to the thing being surveyed - need dedicated servers. But the vast majority of applications do just fine with it."

Hall anticipates further steps to save energy, such as allowing the power of campus computers to be used for other purposes when individual workers aren't there to use it themselves.

"We know that if our campus is fully informed on the benefits of server virtualization and other sensible environmental progress, they'll make the right decision," he said.