Pouchet and others also applauded the growing interest from governmental agencies. Both the U.S. Senate and House of Representatives passed legislation asking that the Environmental Protection Agencys Energy Star program look into the development and use of energy-efficient technology. In addition, the EPA in August announced its Server Energy Measurement Protocol specification for measuring power consumption of servers. The state of California in September also passed a bill calling for a 25 percent reduction in greenhouse gas emissions by 2020, a move that will impact data centers, said Brad Binning, cooling systems business development manager for APC, in West Kingston, R.I.DC power proponents point to the multiple conversion points inside the data centerwhere AC is converted to DC, and vice versaas key places where heat is generated. They also argue that uninterruptible power supplies, or UPSes, used in an AC distribution are not efficient. Click here to read more about the DC power debate. However, several people at the show said that UPSeswhich traditionally have been about 75 to 80 percent efficientare becoming more efficient, as much as 88 to 92 percent. Companies also are looking to put more intelligence into them, enabling them to throttle down when demand is low. Lieberts Pouchet also pointed out that UPSes and other parts of the electrical system only consume about 10 percent of the power that goes into the data center, compared with 50 percent by IT equipment and 25 percent by cooling devices. "Its a smaller slice of the pie," he said. "A 50 percent increase in UPS [efficiency] isnt a big change. A 20 percent improvement in IT equipment is a huge change." Pouchet suggested that while the promise of DC power will entice some people into using it, AC power is established and proven, and the prospects of improving that are better than widespread adoption of DC power. Regarding cooling devices, Pouchet, Binning and others said that relying solely on traditional wall-mounted air conditioning units and raised floors will no longer work as density increases and energy consumption rises. Where six years ago a rack of 2U (3.5-inch) servers consumed 4 kilowatts, that numberwith blade serversis climbing to as much as 24kw and more, and will get to 40kw by 2009, Pouchet said. Businesses need to look at bringing cooling devices into the rows between server racks, and next to the racks themselves, Binning said. "Were getting more dense," he said. "Youve got to look at your cooling. Weve gotten to the point where after 4kw, the raise floor wont work anymore." Check out eWEEK.coms for the latest news, views and analysis on servers, switches and networking protocols for the enterprise and small businesses.
For data center managers and facilities departments, the discussions here focused on such issues as more efficient power supplies and better use of cooling devices. A number of people also made the pitch for greater use of DC distribution in data centers. Johnny Gonzales, director of sales for Pentadyne Power, a flywheel maker in Chatsworth, Calif., argued that DC power would mean 20 to 40 percent less heat generated and 30 percent less power consumed.