Climate protection needs energy efficient data centers - Stulz GmbH

Energy Efficiency in the Data CenterEndnotes1.2.3.4.5.6.7.8.9.10.11.12.13.14.15.16.17.18.19.20.21.22.23.This guide thus complements the BITKOM guide “Reliable Data Centers” and the matrix “Planungshilfe Betriebssicheres Rechenzentrum” (Planning aidfor reliable data centers) which can be downloaded free of charge from the BITKOM website. However, both guides and planning aid are no substitute forexpert advice and support from competent consultants and planners.Fichter, Klaus: Zukunftsmarkt energieeffiziente Rechenzentren. Study carried out on behalf of the Federal Environment Ministry (BMU);(Borderstep Institute); 2007Fichter, Klaus: Zukunftsmarkt energieeffiziente Rechenzentren. Study carried out on behalf of the Federal Environment Ministry (BMU);(Borderstep Institute); 2007US EPA (U.S. Environmental Protection Agency, Energy Star Program): Report to Congress on Server and Data Center Energy Efficiency, Public Law 109-431,2007The Green Grid: GREEN GRID METRICS: Describing Datacenter Power Efficiency. Technical Committee White Paper, February 20, 2007Brill, Kenneth G.: Data Center Energy Efficiency and Productivity, White Paper, The Uptime Institute, 2007ASHRAE, Thermal Guidelines for Data Processing Environments; 2004A unit’s sensible cooling capability is its performance in cooling the air without dehumidifying it.Strictly speaking, it is the ratio between air volume and heat exchanger surface area which needs to be optimized. A large heat exchanger surface arearequires a sufficient volume of air.Although water is frequently used as a cooling medium, it has not proven itself for application as a coolant in data center environments.Return air temperature is only significant when data centers are air-cooled. In installations where all the server racks are water-cooled, for example, theroom air temperature and thus the return air temperature, too, are of no consequence for a data center’s energy efficiency. In such cases more attentionshould be paid to temperatures in the racks’ water system.As mentioned above, another advantage of higher return air temperatures is the higher temperature spread which is possible when water is used as acoolant. An increased spread allows higher operational temperatures on the recooling side and this makes free cooling possible, even at higher outdoortemperatures. The longer free cooling is used, the less energy is needed for the operation of compressors.Swiss Federal Office of Energy: Risokofreier Betrieb von klimatisierten EDV-Räumen bei 26° C Raumtemperatur (Risk-free operation of air-conditionedcomputer rooms at room temperatures of 26° C), Bern 1995Totally Integrated Power: Applikationshandbuch – Grundlagenermittlung und Vorplanung (Application Manual - Basic Data and Preliminary Planning),Siemens AG; 2006Totally Integrated Power: Applikationshandbuch – Grundlagenermittlung und Vorplanung (ApplicationManual - Basic Data and Preliminary Planning),Siemens AG; 2006Uptime-Institute: www.uptimeinstitute.orgBoth publications can be downloaded free of charge from the BITKOM websiteHigh performance buildings: Data centers uninterruptible power supplies (EPRI-Solutions, Ecos Consulting); 2005Swiss Federal Office of Energy: Program “Electricity” Code of Conduct / Label for Uninterruptible Power Supplies (UPS); 2005Code of Conduct on Energy Efficiency and Quality of AC Uninterruptible Power Systems; 2006Code of Conduct on Energy Efficiency and Quality of AC Uninterruptible Power Systems; 2006Code of Conduct on Energy Efficiency and Quality of AC Uninterruptible Power Systems; 2006White Paper: The classifications define site infrastructure performance (The Uptime Institute Inc.); 2001-200637