More efficient data centers and a slowing economy have put the brakes on the rapid growth of electricity use in data centers, according to a study released today.
In an analysis of data center energy consumption, researcher and Stanford University consulting professor Jonathan Koomey found electricity use grew about 36 percent in the U.S. from 2005 to 2010 and 56 percent globally. That pace is lower than the doubling of data center electricity use that happened from 2000 to 2005, he found.
With the growth of cloud computing and data center-connected mobile devices, giant data centers are being built, causing concern over the amount of energy they draw. Koomey estimates that globally data centers consumed between 1.1 percent and 1.5 percent in 2010. The number in the U.S. is between 1.7 percent and 2.2 percent.
Google uses less than 1 percent of the electricity used by data centers, a sign that its data centers are run relatively efficiently, according to Koomey.
The main reason for the overall lower-than-anticipated electricity growth rate for data centers is the economic recession and increased industry focus on efficiency, which started around mid-decade. Also, fewer low-end "volume servers" were installed than predicted in a 2007 EPA report to Congress on data centers, according to the study which was commissioned by The New York Times.
There are a number of available technologies to improve the energy efficiency of data centers, notably virtualization. The design and operation of data centers can also significantly improve the efficiency, such as hot and cold aisles of equipment, or using sensors to optimize cooling. Cooling accounts for about half the energy in data centers.
Koomey said that the growth of cloud computing aids the overall efficiency of data centers. "Because cloud computing installations typically have much higher server utilization levels and infrastructure efficiencies than do in-house data centers (with power usage effectiveness for some specific facilities lower than 1.1) increased adoption of cloud architectures will result in lower electricity use than if the same computing services were delivered using more conventional approaches," he wrote in the study.
Analysts told The New York Times that the main conclusions from Koomey's study make sense, but the slower growth could be temporary.
"The numbers do make sense," Kenneth Brill, founder of the consulting company Uptime Institute, told the Times. "But they shouldn't be taken as indicating the problem's over. There is certainly increasing energy consumption and that should be a concern for everyone."