本文总结了在40多个数据中心进行的能源审计和优化研究。介绍了数据中心能效指标的比较。这些指标包括能源利用指标，如电力使用效率（PUE）、数据中心基础设施效率（DCiE）、机械PUE、电气PUE，以及热或空气管理指标，如旁路和再循环空气流量比。此外，还分析并给出了冷却系统、风扇、UPS损耗和照明占数据中心总功率的百分比。 还考虑了气候带的影响以及与设计荷载密度相比的运行荷载密度。这些指标将降低机房空气冷却效率和整个数据中心基础设施的主要因素结合在一起。能源利用率指标决定了支持机械和电气基础设施的数据中心的效率。有趣的是，数据库显示，小型数据中心[活动地板面积（RFA）<10000 ft2]或企业数据中心的平均PUE高于大型数据中心。 据观察，小型数据中心部分安装了IT设备机架和地板，冷却系统过大且老化，活动地板区域的空气混合（再循环和旁通空气）水平较高，没有实施免费冷却，UPS负载系数较低，IT和设施部门之间没有直接合作。然而，据观察，企业数据中心实施了更多节能技术，如“自由冷却”，以及IT和设施之间更高级别的合作。许多大型数据中心还参加了各种专业IT和设施组织的研讨会，以了解其领域的新进展以及行业最佳实践。 单位:投资:ASHRAE交易，第116卷，pt。2010年奥兰多

This paper presents a summary of the energy audit and optimization studies conducted on more than 40 data centers. Comparison of data center energy efficiency metrics is presented. Those metrics include energy utilization metrics such as the Power Usage Effectiveness (PUE), Data Center infrastructure Efficiency (DCiE), mechanical PUE, electrical PUE and thermal or air management metrics such as bypass and recirculation air flow ratios. Additionally, percentages of cooling system, fans, UPS losses, and lighting to total data center power were analyzed and presented. The impact of climate zone as well as the operational load density compared to design load density were considered as well. These metrics incorporate and integrate together the major factors that decrease the effectiveness of computer room air cooling and the entire data center infrastructure. The energy utilization metrics determine the extent of the efficiencies of the data center supporting mechanical and electrical infrastructures. Interestingly, the database indicated that small data centers [Raised Floor Area (RFA) <10,000 ft2] or corporate data centers have higher average PUE than the larger ones. Small data centers were observed to have partially populated IT equipment racks and floors, oversized and aging cooling systems, higher levels of air mixing (recirculation and bypass air) in the raised floor areas, no implementation of free cooling, low UPS load factor, and no direct cooperation between the IT and the facilities departments. However, enterprise data centers were observed to implement more energy saving techniques such as “free cooling” as well as higher level of cooperation between IT and facilities. Many of those large data centers were also observed to participate in various professional IT and facilities organizations’ seminars to stay informed about new advances in their field as well as industry best practices.Units: I-P