As companies look to make their businesses more eco-friendly, information technology departments are coming under increased scrutiny.

Retail and apparel IT departments have traditionally not had to account for energy consumption. According to a poll conducted by the London-based Economist Intelligence Unit for IBM this summer, 42 percent of businesses don’t even monitor their IT power bill.

So long as computers kicked out the business knowledge needed to gain a competitive edge, few worried about the kilowatt hours burned up to run and, as importantly, chill these systems that will shut down if they overheat.

Many retailers contacted by WWD to discuss the intersection of green thinking and technology were stopped cold by the question. “You hear and see almost nothing about information technology’s contributions to environmental initiatives,” said Jeremy Hollows, former chief information officer at France’s Carrefour and now managing director at InSync Consulting in Oxford, England.

That may be because today’s green initiatives in IT started as cost-saving steps. Still, their positive impact on the environment cannot be dismissed. Companies like Wal-Mart Stores Inc. and Canada’s Hudson’s Bay Co. are using innovative technology like virtualization, and plain old common sense, to reduce wasteful power consumption in their data centers.

Tesco, the 46.6 billion pound ($95 billion at current exchange rates) U.K.-based retail giant, also took steps in recent months to reduce energy use in its data centers. Marks & Spencer’s five-year, 100-point green initiative called “Plan A (because there is no Plan B)” reportedly includes several IT components, but the U.K. retailer declined to comment.

At Wal-Mart, virtualization software from VMware of Palo Alto, Calif., is behind a key initiative that permits the retailer to consolidate processing on fewer pieces of computer hardware, said Nancy Stewart, Wal-Mart’s senior vice president and chief technology officer. Software that once required dedicated hardware, but might not use all its processing capacity, can now run off the same hardware as other software. That means fewer computer servers drawing less energy and occupying less space that needs to be cooled.

“In a data center you have a ton of space,” Stewart said. “You could put a bowling alley through there.”

Virtualization is just one way to get more energy-efficient and comply with Wal-Mart’s mandate that its data center shall not grow.

Typically, companies requiring more computing muscle just add more servers and expand their data centers to accommodate the additional equipment. Those days are over at Wal-Mart, which recently reversed itself on a planned-for data center expansion. This stance runs counter to Google, Microsoft and Yahoo, all of which have massive data center expansion plans — almost like an arms race — whose energy requirements have drawn criticism from environmentalists.

“We’re not going to build another data center,” Stewart said. “We have challenged our [technology] partners to support us in that by adjusting the power coolant requirements of their products. We are telling them it is imperative you build systems that are going to allow us to maintain our current floor space.”

The burning question she has for technology companies and their engineers: “Is it absolutely necessary for you to pump out that much heat?” said Stewart.

It’s a question Hudson’s Bay has for its technology vendors, as well. The retailer measures heat output of hardware and reports that to its vendors with the challenge to improve upon it in the future.

“We are asking all our suppliers to think green. We’re saying, ‘How can you help us help the planet?'” said Jason Wilson, senior general manager of technology at Hudson’s Bay.

To manage the heat generated from computers, Wal-Mart is changing the physical configuration of servers to minimize “hot spots,” where heat output from one unit transfers to another, requiring amped-up air-conditioning. Instead, companies create “hot aisles” and “cold aisles,” where hot blows upon hot and AC is concentrated there only.

Like Wal-Mart, Hudson’s Bay is using virtualization and a number of other strategies to reduce energy consumption in data centers. Tactics include clearing out old cables beneath the floor that block cooling air flow and consolidating three computer rooms into one, where climate control is more efficiently managed.

Next year, Hudson’s Bay will replace power generators’ dirty diesel fuel with cleaner bio-diesel and swap out power-hungry CRT computer monitors with energy-efficient flat screens, he added.

In the U.S., data centers’ power usage doubled in the past six years and is expected to double again by 2011, according to an August Environmental Protection Agency report to Congress.

There’s a huge opportunity to cut back consumption if companies just step back and assess their data center energy usage, said Steve Sams, vice president of global site and facilities services at IBM. “Data centers by nature are energy hogs,” he said. “A typical data center uses 30 times the energy of an office space of the same size.”

Strategies like virtualization, reconfiguring the data center layout and optimizing cool air flow can help companies slash their power bill by half, he said. That means an average 25,000-square-foot data center that eats up $2.6 million in energy each year could spend just $1.3 million, which would be like taking 1,300 cars off the road, said Sams. IBM launched this year a $1 billion “Big Green” initiative to help companies redesign data centers for better efficiency. Cisco Systems, whose technology powers networking, last month announced plans to cut its carbon emissions 10 percent in the next year, and it has moves afoot to bring energy efficiency to the office work spaces much like IBM is doing for data centers.