Data Center Power Use Projections Miss the Mark

Remember all the talk about runaway data center electricity consumption? As it turns out, it might have been overblown -- perhaps even alarmist.

Remember all the talk about runaway data center electricity consumption -- stories that feature analysts, vendors, or industry talking heads wringing their hands over ever-escalating power and cooling requirements.

Turns out, most of that talk might have been overblown -- even a bit alarmist.

That's the conclusion of a new study by Jonathan Koomey, a consulting professor at Stanford University, which finds that data center power consumption grew at a much slower clip from 2005 through 2010 than during the first half of the decade. Koomey's report, Growth in Data Center Electricity Use, 2005 to 2010, suggests that data center power requirements didn't explode (as was feared) but grew instead at a predictable -- and decidedly non-exponential -- rate.

While exploding demand might have seemed like a danger five or six years ago, Koomey writes, power growth actually started slowing by early 2007, thanks chiefly to virtualization. Many market-watchers, basing their projections on energy growth and consumption trends in the first half of the last decade, expected data center energy consumption to effectively double by 2010.

Instead, electricity consumption grew less than 56 percent..

By 2011, Koomey points out, power use in U.S. data centers was "significantly lower" than the rate predicted by the Environmental Protection Agency (EPA) in 2007. This fall-off wasn't the result of improved hardware efficiency, he stresses, but, instead, of "a lower server installed base than was earlier predicted."

Although server consolidation and virtualization efforts account for some of this decline, another big contributor was the 2008 financial crisis, according to Koomey.

The Vanishing Server

Regardless of the specific forces that helped depress demand -- e.g., server consolidation, virtualization, economic recession -- the end result is a reduction in the installed base of enterprise servers.

"The dominant driver of electricity demand from 2000 to 2005 was growth in the installed base of volume servers, which doubled over that five-year period for the U.S. and the world," Koomey writes. "The IDC installed base forecast from 2007 showed slower growth in volume servers to 2010 compared to the 2000 to 2005 period, and the newer forecast reduced installed base growth still further."

Demand for servers hasn't completely slackened.

As growth in the commodity and mid-range markets fell off (relative, that is, to market research projections), demand for high-end server hardware -- including mainframe systems) actually increased -- Koomey explainss.

"Considering the latest installed base estimates for 2010, the growth in volume servers slowed considerably in the 2005 to 2010 period, growing only about 20 percent in the U.S. and about one-third in the world," he writes. "The installed base of mid-range servers fell even faster than expected in the earlier forecast, but high-end servers grew rapidly instead of declining as had been projected earlier."