Citigroup didn't set out to build super-green data centers. In fact, the financial services giant sharpened its focus on carbon consumption after it was halfway through a major project to consolidate 52 legacy data centers into 14 facilities, including three brand new data centers in North America.
But Citigroup's data center team had been thinking about energy efficiency all along, and was ready for action when the company decided that all its new facilities would be certified under the LEED (Leadership in Energy and Environmental Design) program administered by the U.S. Green Buildings Council. They were able to quickly refine their design for Citigroup's new $450 million data center near Austin, Texas to earn LEED Gold status.
"We didn't ignore energy in our designs," said Jack Glass, Citigroup's Senior VP of Data Center Planning. "My electric bill for North American centers is north of $20 million a year. Our team decided that we should be out in front of this issue. LEED was a joint decision between IT and real estate."
The Citigroup team said the additional expense of meeting the LEED standard was minimal. Senior vice president Jim Carney estimates that the cost of complying with LEED was less than 1 percent of the total cost of the facility. "We were doing good energy design anyway," said Carney. "Most of the cost was in documentation, and you get the data center energy savings on day one. We look at the payback as being very short."
Carney and Glass spoke about Citigroup's LEED projects at the DataCenterDynamics New York conference earlier this month.
The Austin data center is a single-story 305,000 square-foot building, which includes 100,000 square feet of data center space divided into four pods with 36-inch raised floors. The facility supports an average of 100 watts per square foot, with some high-density areas hosting much higher power loads. Citigroup broke ground on the project in January 2007, and the building was ready for production in April 2008, a turnaround time of just 15 months.
The data center includes equipment galleries for mechanical and electrical equipment, allowiong Citigroup to move UPS units and computer room air conditioners (CRACs) off the data center floor. To conserve energy, Citigroup is employing variable-speed drives in its pumps, cooling tower fans and air handlers, and using high-efficiency chillers and transformers.
Citigroup is also building a LEED Gold data center in Frankfurt, Germany. The facilities are among a small but growing number of LEED-certified data centers. The LEED standard was designed for commercial office buildings, but a coalition of data center industry groups has released a draft of an energy-efficiency standard to expand the program with customized specs for data centers.
The new Citigroup facilities, along with the consolidation project, are part of a broader effort to remake the company's data center infrastructure in the wake of the 2001 terrorist attacks. "Back on September 11 we could see 70 percent of our technology from our headquarters," said Carney, who said Citigroup was among many Wall Street companies that diversified their facilities after federal regulators urged Wall Street institutions to establish backup data centers outside New York to protect the financial system against any regional disaster.