How green IT saves Citizens Bank $500,000 a year

If you think of "green IT" as nothing more than a vendor-generated buzzword, you might want to take a look at Citizens Bank. The financial institution reports $500,000 in annual savings stemming from a project to optimize its power and cooling practices, and its IT executives believe they have just scratched the surface of potential savings.

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"We did absolutely save a half a million dollars last year and there is far more to save," Lars Linden, senior vice president and director of data center services and operations at Citizens Bank, told an audience at the Storage Networking World conference in Phoenix Tuesday. (Also from the show, "Human race on the verge of a massive upgrade.")

Citizens Bank is pursuing an aggressive virtualization strategy, but it was actually simple changes to the cooling infrastructure that have secured most of the savings thus far, he says. Linden arrived at the bank 18 months ago and has led the project to improve efficiency at seven data centers in the northeast and mid-Atlantic United States for Citizens Bank, which is headquartered in Providence, R.I. and has 1,480 branches, 3,600 automated teller machines and 23,000 employees.

Citizens Bank's total cost of powering the data center, including real estate, labor and all infrastructure, is about $10,000 per kilowatt per year, about half as much as it might cost in midtown Manhattan, Linden said.

One of the first steps toward green IT was eliminating obvious inefficiencies in the cooling of data center rooms. There's no need to keep a frigid temperature throughout a room when only a portion of the space is dedicated to active IT equipment, he noted.

"At least inside my firm we cooled the room, which is what we do in data centers, right?" Linden said during an interview with Network World after his speech. "But I don’t need to cool the room, what I need to do is provide cooling to those racks that are hot."

One obvious source of waste involved fans and spot coolers placed on the wrong side of the racks.

"Oftentimes I've walked into data centers where the facilities guys have put fans and spot coolers at the backs of racks, because it's hot. But it's supposed to be hot [because that's where heat is being expelled]. What you want to do is make sure it's cool on the front side of the rack," Linden says.

In some cases, Citizens Bank had provisioned more cooling capacity than it could ever consume "because we didn't have enough power going into the data center to generate that much heat," he said.

Before the green IT project, the bank was keeping data center rooms at 66 or 67 degrees Fahrenheit, and is now aiming for 71 degrees with 45% to 50% relative humidity and taking advantage of cool outside air with waterside economizer systems.

But that's just the beginning.

"I aspire to get up into the 90s," Linden said of his target data center temperature. "If I can run my data center effectively at 90-plus degrees Fahrenheit, I get absolutely tremendous savings in terms of cooling." While the overall temperature would be desert-like, Linden said he aims to "deliver the cold air at, say, 65 degrees to the fronts of the servers and the fronts of the storage arrays. As long as I'm doing that, I don't care if the walls are hot. I don't care if the floor is hot. It doesn't matter."