The project, involving high-density computing systems that use server and storage virtualization, and energy-efficient power and cooling systems, is part of IBM's goal to double its data-center capacity by 2010 without increasing energy usage or carbon emissions, says Rich Lechner, IBM's vice president for IT optimization.

"This is about growth," Lechner says. "The reason we're building these data centers is we continue to have growth in our clients' demands. It's about growing in an eco-friendly way."

The Boulder data center, currently measuring 225,000 square feet, will increase to more than 300,000 square feet once the expansion is complete next year. The new space will be 45 percent more energy efficient than a typical IBM data center, due to efficient building designs, new lighting systems, and highly efficient air conditioning and extensive use of virtualization, Lechner says.

Virtualization technology will also be applied to the existing 225,000-square-foot data center to make it more efficient. Through a variety of methods, such as use of software called PowerExecutive that manages and monitors power consumption, IBM has reduced its carbon emissions 40 percent since 1995, according to Lechner.

The Boulder data center hosts IBM's internal operations as well as those of customers, such as the United States Tennis Association. The IBM facility hosts scoring applications and Web servers for the tennis organization, he says. The Boulder expansion is being completed partly to accommodate a $480 million, five-year agreement with a new customer IBM has declined to name publicly.

IBM's decision to expand in Boulder was influenced by $100,000 in tax and fee rebates from the city as well as a $632,000 grant from the Colorado Office of Economic Development and International Trade to train the data center's new workforce and other IBM employees.

On May 10, IBM announced Project Big Green, in which it will spend $1 billion per year to increase IT energy efficiency both for itself and clients.