Data center power consumption through the roof

That's one serious electric bill. U.S. data centers consumed the equivalent of the power generated by five 1,000-kilowatt power plants in 2005 - or about 1.2% of the country's electricity consumption - resulting in total utility bills amounting to $2.7 billion.

Those observations were among the findings in a study authored by Jonathan Koomey of Lawrence Berkeley National Laboratories in Berkeley, Calif., for AMD. The study found that in 2005, total data center electricity consumption in the U.S., including servers, cooling and auxiliary equipment, was approximately 45 billion kWh, with total data center power and electricity consumption for the world estimated to cost $7.2 billion annually.

The report also examines the growth in electricity demands since the year 2000, concluding no surprisingly that in about seven years energy use has doubled. Koomey found that about 90% of the increase was due to the rise in the number of low-volume servers, those priced below $25,000.

While these low-volume systems have become increasingly powerful, energy usage per server has increased only slightly from about 190 watts per server in 2000 to about 220 watts per server in 2005. As a result, the spike in energy consumption is due mainly to the fact that the number of volume servers has risen dramatically, jumping from about 12 million in 2000 to 26 million in 2005."Mainly this is a story of volume servers becoming much more common," says Koomey. In addition, the low-volume systems are increasingly dense - with blade servers and multi-core machines - making it even more important for organizations to consider energy efficiency in charting data center deployments, Koomey says.

"In the data centers that we've done benchmarking on you typically find a third or half of the racks are empty because you've got air cooling and a lot of restraints in how many servers you can pack in," he says.