Another fairly straightforward place to launch energy efficiency improvements is by looking at the data center's utility bill a basic practice all too often not done by the IT department. Tucillo recommends CIOs work together with CFOs to examine utility bills in an effort to uncover those areas that could potentially be made more energy efficient. While monthly costs do not always correspond to inefficiencies, they can at least highlight in plain financial terms where opportunities for improvement may exist.
3. Adjust for Virtualization
Once initial assessments are done, CIOs can then examine where to trim electricity usage. While specific strategies will vary, server virtualization is a common strategy and one that can reduce energy consumption and costs significantly by replacing many under-utilized physical servers with a single box. Yet to realize maximum savings from virtualization, or any tactic aimed at efficiency, you've got to consider the ripple effect on the overall data center operations.
"If you have taken your average server and storage device from under 20 percent utilized to somewhere around 70 to 80%, you also should ensure that you've matched your power requirements to that utilization," Tucillo explains. When deploying virtualization, the workload density of certain servers increases, so power and cooling need to be adjusted accordingly for the racks housing those servers as well as for the racks from which servers may have been removed.
A review of the cooling architecture can often lead to significant savings for minimal effort. "I've seen all kinds of ranges for energy efficiency improvement," Tucillo says, "spanning from 40 percent to 20 percent. This can be as straightforward as moving air conditioners closer to those rows of virtualized servers, a strategy called close-coupled cooling. The idea behind close-coupled cooling is to have more control over the delivery of cool air and the capture of hot air. "You want to employ the right cooling required for a particular rack at the time it is needed," Tucillo explains.