Power Management Features

Data centers are sized for peak conditions that may rarely exist. For example, in a typical business data center, daily demand progressively increases from about 5 a.m. to 11 a.m. and then begins to drop again at 5 p.m. However, server power consumption remains relatively high as server load decreases. In idle mode, most servers consume between 70 and 85 percent of full operational power. Consequently, a facility operating at just 20 percent capacity may use 80 percent of the energy as the same facility operating at 100 percent capacity.  Power management features built into server processors can reduce power use when the processor is idle, but often these features are often disabled because of concerns regarding response time; however, this decision may need to be reevaluated in light of the significant savings this technology can enable.  In a 5,000-square-foot data center model, we assume that idle power draw is 80 percent of the peak power draw without power management, which can be reduced to 45 percent of peak power draw when power management is enabled. In this scenario, power management can save an additional 86 kW, or eight percent, of the unoptimized data center's power load.