This document discusses greening data center operations. It notes that data centers consume large amounts of power, with US data centers using over 125 TWh of power per year. It then discusses measuring data center efficiency using Power Usage Effectiveness (PUE) and provides examples of efficient PUE levels. It also describes optimization strategies used at the SDSC data center like thermal containment and increased supply temperatures. Finally, it outlines a conceptual design for an ultra-efficient data center in collaboration with McGill University, aiming for a PUE of 1.06 using free cooling, ice storage, and low-cost hydroelectric power.
2. Data Centers Are Enormous Users of Power
US Data Centers (TeraWatt Hours per Year) US Televisions
(248 Million Units)
125
61
27
Sources: Report to Congress on Server and Data Center Energy Efficiency Public Law 109-431;
U.S. Environmental Protection Agency ENERGY STAR Program, August 2, 2007; Kaufman, Ron.
Television's Hidden Agenda. TurnOffYourTV.com, 2004
SAN DIEGO SUPERCOMPUTER CENTER  at the UNIVERSITY OF CALIFORNIA, SAN DIEGO Cyberinfrastructure Services Division
14. ResultsÂ
Supply Temperatures Annual Energy Use Mechanical Cooling Needed Water Usage
Water Cooled
Hours of Free Additional Load
Air Cooled
Cooling / year PUE at Extreme Cost
Cost Evaporation +
Air Cooled Water Cooled Energy Weather Blowdown ($5.52/1,000
( $0.058/ kWh) Hours per Year1 Carry Over
(wetbulb = gal)
68.7°F)
°C °F °C °F hrs/yr % of yr kWh/yr2 $ tons gallons gallons $
10% 90% 29.4 85.0 23.9 75.0 8,532 97% 1.06 74,543,000 $4,323,000 228 0 33,200,000 8,100,000 $228,000
SAN DIEGO SUPERCOMPUTER CENTER  at the UNIVERSITY OF CALIFORNIA, SAN DIEGO Cyberinfrastructure Services Division
15. Potential FacilityâRelated Cost Savings
Assumptions
⢠5 MW IT Load
⢠24x7 Operation
Typical Local DC Efficient Local DC Ultra-Efficient
⢠2.0 PUE ⢠1.35 PUE ⢠1.06 PUE
⢠10 MW Consumption ⢠6.75 MW Consumption ⢠5.3 MW Consumption
⢠$0.10/kWh Power Costs ⢠$0.10/kWh Power Costs ⢠$0.05/kWh Power Costs
⢠$8.8M Power Bill ⢠$5.9M Power Bill ⢠$2.3M Power Bill
Potential Cost Savings of 74% and Energy Savings of 47%
Though Facility Changes Alone!
SAN DIEGO SUPERCOMPUTER CENTER  at the UNIVERSITY OF CALIFORNIA, SAN DIEGO Cyberinfrastructure Services Division