Energy-efficient cooling is a hot topic in the data center industry, given the enormous amounts of energy applied for the purpose.

Core4 Systems says its technology can deliver a near three-quarters reduction in cooling power demand, all without turning to another technique that's gaining some traction in the industry – using outside air to do the job.

Instead, the Napa, Calif.-based startup says it has put together a suite of technologies – energy efficient compressors, low-power fans and coils that maintain humidity at more optimum levels – that it can use to replace or retrofit existing cooling systems.

Its first customer, Santa Rosa, Calif.-based internet service provider, said its Core4 system has cut its cooling energy use by 72 percent and water use by 28 percent. That has helped it save about $12,000 a month in electric bills and secure a $153,000 rebate from utility Pacific Gas & Electric.

Funded by a $600,000 seed round and the $625,000 that paid for its system, Core4 is now aiming for what it sees as a $6 billion market for new and upgraded data centers, David Nurse, president and chief operating officer, said.

Analysts briefed on Core4's offering say it could fit in well with the industry's imperatives to cut energy use wherever possible.

Data centers use about 1.5 percent of the nation's power – about 2.5 percent in Northern California – and the U.S. Environmental Protection Agency estimates that energy consumption will double to 100 billion kilowatt-hours by 2012, costing data center operators $7.4 billion in power bills (see Data Centers Could Hit 'Resource Crisis').

That's led to a big push among data center operators and the companies that serve them to find ways to cut power demand, from the servers themselves to the systems that keep them running (see Symantec Report: Green IT Now 'Essential Item').

Given that air conditioning can account for up to half or more of a data center's overall power needs, cutting those costs down is a good way to start (see Green Light post). 

But one new energy efficient technique Core4 isn't very excited about is using outside air to cool data centers.

Known as air side economization, pulling in cool air from outdoors is becoming a bigger part of some data center cooling systems of late.

Giants like Google. Intel and Sun have been experimenting with it, and new data center builder Advanced Data Centers is planning on using outside air to cut its new Sacramento, Calif.-based data center power use (see Advanced Data Centers Claims Super-Efficiency). 

Industry group Green Grid has endorsed the idea in a way, by putting together tools and maps to show what parts of the country offer the coolest air to help in site selection for new data centers (see Green Grid: Free Cooling for Data Centers).

But Rick Cockrell, chief technology officer for Core4, pointed out the penalties for cooling that way, including the extra energy needed for fans to pull air through the filters that need to be in place to keep out the dust and other contaminants in outside air.

"That extra energy is a huge penalty for air-side economizers," he said. And even with filters, increased amounts of dust, combined with the variables in temperature that can come, can mean higher rates of equipment failure, he noted.

He pointed to Intel, which conducted a 10-month study of a data center using outside air with no humidity controls and minimal filtering in New Mexico. The study reported a 74-percent energy savings, while equipment failure rose to 4.46 percent in the experimental center, compared to 3.83 percent failure in a data center using traditional cooling (see Run Data Centers Hotter, Say IT Giants).

But as Cockrell pointed out, that represents an 84-percent increase in equipment failure rate – and with dust buildup likely to increase over time a data center uses outside air, that failure rate could increase past the 10-month window Intel provided, he noted.

In the meantime, other startups that have developed new angles on the art of keeping buildings cool are tackling the data center market (see Eleven Cool Names and Concepts to Watch in Air Conditioning).

Ice Energy, which makes an ice-cooled rooftop refrigerator that allows users to make ice at night when power is cheap and use it for cooling during expensive peak power periods on hot summer afternoons, has announced it is entering the data center market with a partnership with Data Aire (see Green Light post).

And Optimum Energy, which has customers including Adobe using its software to control air conditioners and save power, last week landed a $4.5 million investment to expand its business (see Green Light post).

How well these new entrants in the field will compete against, or integrate with, established system providers like Liebert remains to be seen.

Konkana Khaund, analyst with Frost & Sullivan's environment and building technologies practice, thinks that Core4's focus on designing custom systems could give it an advantage.

"It's a custom spec product, so there's a consulting component prior to installment... which data centers very much need," she said.

Of course, others are making moves into the energy efficient data center consulting field, including Sun Microsystems and General Electric (see Sun: Data Center Efficiency for Everyone and GE Looks to Data Center Efficiency).