DC Power Production, Delivery and Utilization
In a 2001 survey of 45 data center managers, Primen (EPRI So- lutions), found that most data centers had an electrical inten- sity of about 40–50 watts per square foot.10 However, respon- dents anticipated higher power densities, perhaps as high as 150 watts per square foot.
Indeed, the average electric intensity of today’s data cen- ters is higher than in 2001. The power requirements cited by CEETHERM illustrate this, as does an anecdote from one data center manager in November 2005:
Wed planned for 50 to 70 watts per square foot and we’re blow- ing past those numbers.Wed planned for 20% growth per year [in electricity demand], but we’re at 45% growth per year.
Tom Roberts, Director of Data Center Services,
Trinity Information Services, Novi, Michigan
Consortium for Energy Efficient Thermal Management
To address research challenges associated with thermal and en- ergy management of electronics, the Consortium for Energy Ef- ficient Thermal Management (CEETHERM) was initiated in 2002. This collaboration brings together researchers at the Georgia Institute of Technology and the University of Maryland who have been focusing on related problems for many years, working with industry to sponsor research of a pre-competitive nature.
The consortium concentrates on research topics of medium- and long-range interest as identified in discussion with mem- bers. Current research emphasizes package- and module-level cooling schemes for next-generation electronic components, compact fuel cell technologies, combined heat and power ap- proaches for energy efficiency, and computational modeling schemes to aid rapid prototyping, design, and optimization. Technical review meetings are held twice a year, on an alternat- ing basis, on the two university campuses.
For more information, visit http://www.me.gatech.edu/ CEETHERM/Purpose.html.
An EPRI White Paper
Figure 8. Data center rack
Increasing numbers of servers fill multiple racks such as these in data centers, requiring significant amounts of power.
The need to provide more and more power to new blade server technology (Figure 9) and other high-density computing de- vices has made reducing electricity costs a pressing goal within the data center industry. Multiple approaches are under con- sideration to increase energy efficiency, including a multi-core approach, with cores running at reduced speed, and software that enables managers to run multiple operating system im- ages on a single machine. However, one of the more intriguing options is DC power delivery. In fact, a data-center industry group formed in late 2005 with support from the California Energy Commission through the Lawrence Berkeley National Laboratory is exploring the challenge of determining how DC power delivery systems can reduce energy needs and enhance the performance of data centers.