Fortune Data Centers says its newly opened data center in San Jose, Calif. could be among the most energy efficient in Silicon Valley – in part because it bucks one of the industry's most pervasive architectural trends.

That's the "raised floor" that is synonymous with data centers around the country. But Fortune's new data center uses concrete slab floors, and that saves a lot of money on energy costs, said Fortune CEO John Sheputis.

"It's common sense," he said Tuesday. "Pushing cold air down under a floor and then pushing it back up to cool data centers really requires a lot of power." By putting the cooling system in the ceiling and letting cold air fall, as physics demands, Fortune's new data center is able to cut typical fan power bills by up to 75 percent, he said.

That simple architectural decision – along with more typical choices like using industrial water-cooling systems rather than air conditioning systems – adds up to big energy savings, Sheputis said.

That efficiency is measured using a power use effectiveness, or PUE, ratio that represents the total amount of power consumed by a data center divided by the amount used for computing.

Fortune Data Center's new 40,000-square-foot center – the first of two the company plans to build – has a PUE of about 1.37, Sheputis said. Older data centers tend to have a PUE of about 1.5 to 2, though newer ones are seeking to bring that ratio down.

NetApp, for instance, received a $1.4 million efficiency rebate from Pacific Gas & Electric Co. last year for reaching a PUE of 1.3 at its Sunnyvale, Calif. data center, and Google says six of its large data centers achieve an average PUE of 1.21.

Data center facility operations – cooling chief among them – can account for about half a data center's total power load, so lowering that PUE is a big deal. Advanced Data Centers is building a data center near Sacramento that it says will have a PUE of 1.1 – a goal that pushes the realm of the possible, experts say (see Advanced Data Centers Claims Super-Efficiency).

Still, given that data centers suck up 1.5 percent of the nation's power – about 2.5 percent in Northern California – saving power is becoming a critical factor to consider when building new ones (see Sun: Data Center Efficiency for Everyone and GE Looks to Data Center Efficiency).

The U.S. Environmental Protection Agency estimates that data centers and servers will double that energy consumption to 100 billion kilowatt-hours by 2012, costing data center operators $7.4 billion in power bills (see Data Centers Could Hit 'Resource Crisis').

Fortune Data Centers estimates that moving IT load from a typical data center with a PUE of 2 to its new data center could save a tenant about 40 million kilowatt hours of electricity per year, or about $4 million per year in power costs.

Then there are other "green" aspects to the data center, such as the fact that Fortune did "a ton of recycling and reuse" of materials in the former disk drive component factory that it converted to its data center, Sheputis said.

That choice "saved us tens of millions of dollars" from the roughly $100 million price tag of the project, which includes Fortune's spending as well as that from previous owners of the facility, he said.

It also helped earn the new data center a tentative Gold LEED (Leadership in Energy and Environmental Design) rating from the U.S. Green Building Council, Sheputis noted.

Fortune – which is funded by an unnamed $1.5 billion real estate fund of a large pension fund advisor – also uses mechanical chillers and water towers in lieu of refrigerant-based cooling systems, and installed plastic curtains to keep hot and cold air from mixing, he said.

Fortune didn't use every data center efficiency trick in the book. For example, it hasn't chosen to use outside air for direct cooling of IT equipment, something that a small but growing number of data centers are using (see Green Grid: Free Cooling for Data Centers and this Green Light post).

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