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Can fresh air help companies cool computers more cheaply?

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American



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High-tech giants like Google and Microsoft are getting socked with high electric bills to cool ever-expanding data centers (computers don't like heat or humidity). In an attempt to lower costs, some of them are using fresh air to help maintain optimum temps–and now there's a way to gauge how much money and energy they can save by taking this tack. The Green Grid, a Portland, Ore.,–based consortium of 208 businesses (including Google and Microsoft) with megadata centers, today launched a free tool on its Web site designed to help U.S. and Canadian companies figure out how Mother Nature can help them keep their cool—and how much dough and energy they can save by tapping her reserves.

Potential savings depend on a number of factors, including where a data center is located, the local cost per kilowatt hour of power, how much energy a facility uses and the specific temperatures and humidity levels required, according to Mark Monroe, a member of the Green Grid's board of directors and Sun Microsystems's director of sustainable computing.

The Green Grid's software calculates the number of hours per year that a data center could use ambient temperature for cooling with the help of historical atmospheric data from 2,186 U.S. and Canadian weather stations collected between 1999 and 2008.

Based on this free cooling calculator, a company with a one megawatt (1,000 kilowatts) data center in San Jose, Calif. (zip code 95101), for example, that pays about 13 cents per kilowatt hour, could save $66,000 per year using cool outside air rather than air conditioning. The data center could save another $160,000 per year if it liquid cooled certain areas of the facility using a network of pipes filled with water drawn from cooling towers when the outdoor temperature is lower than the temperature indoors (instead of running a chiller to keep the water cool).

"Until recently, energy has been cheap," Monroe says, "so building designers had gotten complacent in terms of energy management in a facility's cooling systems."

A report in August 2007 issued by the Environmental Protection Agency (EPA) estimated that data centers consume 1.5 percent of all energy used in the U.S., and that this consumption is doubling every five years.

Image © Green Grid

Larry Greenemeier is the associate editor of technology for Scientific American, covering a variety of tech-related topics, including biotech, computers, military tech, nanotech and robots.

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