Power, Environmental Concerns Driving Data Center Design

Higher temperatures, power availability, and efficiency are among a host of factors impacting how and where data centers, particularly those where "green" has become a big factor for customers, are being built.

K.C. Mares, president and chief energy officer of MegaWatt Consulting, a Reno, Nev.-based data center consulting firm, said that controling power use and showing environmental responsibility are important factors when building new data centers.

Mares, speaking before an audience of data center administrators and technology providers at the Green Data Center Conference, held this week in San Diego, said that the U.S. is going through a period of fast growth in the number of data centers being built.

"Last year, we had more data center buildouts in the U.S. than ever," he said. "The industry has become a big real estate market. Last year may have been one of the worst ever for real estate. But we're seeing a lot of newcomers building data centers."

The growth in data, and the need to better manage that data, is the primary driver for data center growth, Mares said. "The amount of data being stored is doubling every 18 months," he said. "So buying storage to keep up with that growth is important for the data center business."

But while data storage continues to push data center growth, the need to control power use and show environmental responsibility are impacting how and where those data centers are being built, Mares said.

Location will be a big issue going forward thanks to an expected mass closure of coal-fired power plants coming in the wake of Federal regulations first discussed in the 1970s but which were only recently finalized.

Mares said that coal accounts for about 50 percent of electrical power generation in the U.S., and that about 40 percent of coal-fired power plants are expected to be shut down before 2020 because their operators have determined that investment in technology to meet environmental regulations was too high.

"We'll be seeing a lot of new locations for building data centers in response to where power is being generated," he said.

Data center power efficiency has grown significantly in the last few years as measured by PUE, or Power Usage Effectiveness, Mares said.

PUE, as defined by the Green Grid organization, is the amount of power entering a data center divided by the power which is actually used to run the computer infrastructure within it. PUE is expressed as a ratio. A PUE of 2.0 means that a data center consumes 2 kWh of power for every 1 kWh of power used to run IT equipment, with the extra power used to run cooling, power equipment, lighting, and other facility operations.

"The average PUE is 1.8 in the U.S.," Mares said. "That's a 20-percent improvement in two years. We're seeing some data centers with PUE as low as 1.1. This drop comes from the building of a lot of new, large, more power-efficient data centers."

One big factor in increasing PUE is raising the temperature of the air inside a data center from the 60-plus-degree range in which they traditionally operated, Mares said.

"Higher temperatures are the new norm," he said. "It's now 70, 80, 90, or even 100 degrees. The hardware can handle it. Now the main issue is operator comfort. This includes both physical comfort and mental comfort from the point of view of getting used to the idea of running equipment at higher temperatures."