Server power consumption rises unabated

Various environmental interest groups are warning data centre managers that if steps aren't taken to reduce consumption, power availability problems will continue to grow and costs will rise.

A new study conducted by Stanford University professor Jonathan Koomey, Ph.D., and sponsored by AMD indicates that the current growth in server energy consumption levels will necessitate additional capacity equal to more than 10 1,000-megawatt (MW) power plants by 2010.

Using server data from IDC, the study documents energy use across the world.

The study found that between 2000 and 2005, servers in the U.S. and Europe comprise about two-thirds of the world's total electricity use, with Japan, Asia/Pacific and the rest of the world each falling between 10% and 15% of the total.

The most egregious offenders

But over the next three years, the share of total server electricity use from U.S. data centres will likely decline from 40% in 2000 to about one-third, while those in the Asia/Pacific region will increase their share from 10% to about 16%.

Server electricity use in the Asia/Pacific region grew at a 23% per year, compared with a world average of 16% a year, making the region the only one with server electricity use growing at a rate significantly greater than the world average.

At this rate, the absolute electricity consumption for servers in the Asia/Pacific region would more than double between 2005 and 2010, requiring electricity capacity equal to output from two new 1,000 MW power plants.

According to Koomey, the increase in power consumption is attributable to massive server implementations that coincide with the region's economic growth.

"There's no question that the modern world has been adding more capacity into their data centres. There is a demand for compute power for things like Web 2.0 and video on demand," said Koomey, who is also a project scientist with Lawrence Berkeley National Laboratory .

Western Europe's growth rate of 17% was slightly above the world average, while growth rates in the other regions were lower than the world average.

Power crisis avoidance

At the same time, experts have identified several methods and tools that can help data centre managers gauge and control power consumption.

According to a recent EPA report, even minor efforts by data centre managers could cut U.S. data centre energy consumption by 20%.

If the EPA report's 20% savings is applied to Koomey's projections for global data centre electricity use in 2010, total savings would equal approximately five 1,000 MW power plants, offsetting nearly half the expected growth in global data centre electricity use in 2010.

"It isn't that servers are consuming more power, but the prices of servers have dropped and people are buying more of them to accommodate their business needs," said Brent Kerby, a product marketing manager at AMD. "We are trying to educate people on technologies that can drive better efficiencies, like virtualisation and power management."

The least aggressive power-saving options include turning off idle or "comatose servers," which make up about 10% to 30% of servers in a data centre, Koomey said.

Other ways include using available power management features, consolidating underutilised servers with virtualisation and shutting off unused servers, said Kerby.

Power efficiency measuring tools popping up

Several vendors and industry organisations have developed online tools to measure data centre efficiency and promote power savings.

Standard Performance Evaluation Corp. recently released its SPECpower-ssj2008, the first industry-standard benchmark that measures power consumption in relation to performance for servers.

The SPEC benchmark is based on Java workloads, so it is not all-encompassing, but organisations like the U.S. Environmental Protection Agency (EPA) -- which is expected to produce an Energy Star rating for servers -- will likely adopt the methodology, Koomey said.

"The SPEC Power metric measures individual servers. We are still a ways off from having a standard to measure power efficiency of the whole data centre, on site," Koomey said.

The Uptime Institute's power use tool, the True TCO Calculator allows you to input your data centre infrastructure information into a spreadsheet and calculates the costs to build and operate a new data centre. It includes estimates of components like site infrastructure capital costs, computer equipment costs, energy bills and other operating expenses.

APC, a power and cooling services company, has a free Web-based tool that rates data centre power efficiency.

The Efficiency Quotient online evaluation tool gives you a free, fact-based rating of current efficiency levels; recommendations for next steps for improvement; and access to related white papers, tools and information.

The tool gives a measurement based on a uninterruptible power supply efficiency curve during various workloads, using APC measured values. It can also measure other power supplies to give DC managers a baseline to improve their efficiencies, said Carl Cottuli, APC's VP of data centre science.

The efficiency loss calculations come from manufacturers, real measurements, and predictions, Cottuli said.

Of course, the Efficiency Quotient also doubles as an APC marketing tool and requires that you fill out your name, telephone number, company type and the APC products you would be interested purchasing.

Dell has an online tool as well, the Datacenter Capacity Planner, which measures infrastructure "Greenprint" -- power (kilowatt-hours), cooling (BTUs) and performance (million instructions per second). It is proprietary and measures only capacity in Dell server environments.