Users have somewhat of green IT because vendors tend to over-hype products as "green."  But the move toward more efficient and, hopefully, less expensive IT processes is an unavoidable trend, say industry professionals due to speak IT Roadmap, a Network World event.

Green IT is "absolutely real," says James Carney, executive vice president of data center planning at Citigroup in New York. "The operational efficiencies and cost savings that are associated with successful green projects are what make them very useful or important to someone like We don't do it just to be good corporate citizens. We do it because we can optimize our cost and efficiency."

Citigroup takes a holistic view of green IT that goes beyond the company's power usage, says Michelle Erickson, who is leading a project to promote environmental sustainability in the company's global IT infrastructure. In addition to power management, goals include reducing use of paper, reducing travel, maintaining a sustainable supply chain, and educating employees.

"Green is not just about energy consumption," Erickson says. "It's also about making sure your employees have the collaboration tools necessary to work productively, efficiently as a team, and enable them to work anywhere from around the world."

At the data center level, Citigroup's green projects started a few years ago, driven largely by a tremendous increase in the number of physical servers. Citigroup had 52 data centers in 2005 and plans to reduce that to 14 by 2010, Carney says. By using , the company has also dramatically slowed down its server growth.