AdaptivCool is taking the Goldilocks approach to data center cooling – keep the air temperature neither too hot, nor too cold.

It does that through what may seem a blindingly simple solution – instead of just blowing cold air all over the place, simply blow it into where it's needed.

To do this, the Milford, N.H.-based division of Degree Controls makes floor tiles with fans linked to temperature controls. Those can replace the tiles common in "raised floor" data centers, where air-conditioned cold air is pushed from under the floor up into the aisles that house the servers that need cooling.

"We do not install new air conditioners or anything – we do not touch the servers or racks. All we do is change the tiles," said Rajesh Nair, chief technology officer for AdaptivCool.

Those fan-and-sensor enabled tiles blow the cold air into places where servers are running hot, and ignore places where servers aren't generating that much heat, he said. AdaptivCool also makes sensor-enabled roof units to such out hot air in a similarly selective manner, he said.

And that simple step can allow data center operators to turn down total cooling power loads by up to 30 percent, yielding 15 percent to 20 percent overall energy savings – or, as Nair put it, yielding a one to two-year payback on installation costs.

Without such an approach, no matter how energy-efficient central cooling systems are, "You're still going to have some hot racks somewhere, speeding everything else up and increasing inefficiency," he said.

AdaptivCool's offering is just one piece of a major push underway to make power-hungry data centers more energy efficient.

Data centers use about 1.5 percent of the nation's power, and that's expected to double to 100 billion kilowatt-hours by 2012, costing data center operators $7.4 billion in power bills, the EPA predicts (see Data Centers Could Hit 'Resource Crisis').

That's led to both a big push by big data center users to make internal improvements to their designs, as well as investments in startups that can offer new technologies to drive data center efficiency (see Sun: Data Center Efficiency for Everyone and Advanced Data Centers Claims Super-Efficiency).

Optimum Energy landed $4.5 million in June for its software that helps control central air conditioning units for office buildings and data centers (see Green Light post).

And startup Ice Energy, which makes ice at night to boost air conditioner efficiency during the day, is seeking data center customers as well through a partnership with Data Aire (see Green Light post).

Making central cooling systems more efficient is one way to cut data center power costs. So is using cold air from outside the data center, or so-called "air side economizing" (see Core4 Promises Big Energy Savings for Data Center Cooling and Green Grid: Free Cooling for Data Centers).

And AdaptivCool's technology is mainly a more accurate way to deliver cold air already being segregated from hot air in data centers that use hot aisle and cold aisle containment (see Sun's Take on Green Datacenters in 2009).

Then there's the sensor part of the equation – knowing where cooling is needed is an important step in using it more efficiently. That's been the focus of established data center control system makers like IBM and HP, as well as startups like Redwood City, Calif.-based Sentilla (see The Race for the Data Center's Brain).

AdaptivCool makes its own sensors, Nair said, but can also use sensors already in place.

The company's technology is suitable for most of the data centers out there, Nair said. So far, AdaptivCool has installed its products in six data centers, and is working with several others on future installations, he said.

It also has a sales partner in data center services company Electronic Environments, according to this August Data Center Dynamics report.