If green accounts for 50 percent of the electricity generated, the price rises to $0.063 per kw-hr and carbon reduction rises to 46 percent.
If the power is 100 percent green, the rate hits $0.093 per kw-hr and carbon reduction hits 95 percent.
There is no doubt that greenhouse gas emission controls on power plants under the new EPA regulations will make electricity more expensive for data centers, which creates an incentive for energy efficiency, according to a recent article in The Data Center Journal.
"For data centers, this policy clearly translates into higher operating expenses, although on the upside,' it could make certain energy-efficiency improvements seem more economical," the article, published shortly after Obama's directive, stated.
The article goes on to say, "In some cases, investments in efficiency — particularly in data centers with high PUEs [power usage effectiveness] — could offset or even reverse increases in energy costs resulting from new regulations.''
(A PUE, established by the Green Grid, is a ranking of the energy efficiency of a data center; the lower the PUE, the more energy-efficient it is.)
Are data centers ready?
The attention to energy efficiency in data centers varies, says Nicole Peill-Moelter, the director of environmental sustainability at Akamai Technologies, a provider of application and content delivery technology and services.
Akamai operates data centers globally, including in California, and contracts with third-party data centers there, too, says Peill-Moelter. While Akamai constantly works to improve energy efficiency at its data centers, some of the third party data centers Akamai uses are behind the times.
"I've gone to some of the data centers where we have equipment hosted and a lot of these data centers don't have implemented even the basic energy efficiency measures," Peill-Moelter says. "They pass the costs directly onto their clients."
There are a number of steps data center operators can take to improve energy efficiency and the IT industry overall is already moving on many of them.
- Energy-efficient processors. Each generation of processors from Intel, AMD and the rest ushers in improved measures of performance per watt with multicore and multi-threading designs.
- Servers. Software can reduce the total energy draw of data center servers by pushing more data through older servers to improve their efficiency, says Akamai's Peill-Moelter. In addition, new network software can identify "zombie servers" in the data center that aren't operating, but still drawing power, because the application or business unit assigned to that server doesn't use it anymore.
- Virtualization. Many servers operated at as little as 10 percent to 15 percent utilization. But running multiple virtual servers in one physical server can increase utilization to the range of 40 percent to 50 percent, requiring fewer physical servers.
- Cloud computing. Contracting with a cloud service provider relieves a company of some of the energy expense of running its own data center, but because the compute cycles have to be created somewhere, the cloud provider's costs will in some way be passed onto the user.
- Data center cooling. Adopting a hot aisle-cold aisle strategy, physically separating the hot aisle (the backs of servers where heat is generated) from the cold aisle (where people work) keeps hot and cool air from mixing, Peill-Moelter says, and reduces the strain on air conditioning systems.
Sign up for Computerworld eNewsletters.