AI 中文总结
本研究分析数据中心的可持续性与循环性，指出现有能源指标的缺陷，提出更完善的指标，探讨制冷与用水、废热回收等的权衡，及数据中心与电网的复杂关系与缓解措施。
AI 中文摘要
本报告分析了数据中心（DC）的可持续性与循环性，揭示了其中存在的协同效应与权衡：电源使用效率（PUE）指标过于粗糙，将制冷与电力供应混为一谈，错误地将服务器风扇能耗和转换损耗归为IT能耗，且该指标衡量的是基础设施效率而非计算效率，而基础设施效率已表现出色，但计算能耗却在急剧增长。因此，数据中心需要更完善的能源指标，应涵盖：i）计算效率，ii）转换效率，iii）制冷开销。制冷能耗与现场用水、上游用水之间存在权衡：现场用水可降低制冷能耗，同时减少发电环节的上游用水量；对于“湿”电力（发电耗水多的电力），几乎不存在竞争，值得投入更多现场能耗以节约电力及相关上游用水；对于“干”电力（发电耗水少的电力），则存在权衡。废热回收可实现能源循环性，但用途有限且能源品质不同，这一事实未被当前指标反映，更优的指标应考虑废热回收避免的能源量，而非回收的能源量。材料循环性可通过在数据中心场景下解读9R框架实现，提升循环性的措施可分为产品设计、工艺设计与商业模式、材料选择、运行条件四类，它们对所有循环性层级均有影响。数据中心与电网的关系复杂，现代数据中心给电网带来新挑战，缓解措施包括电池存储与现场发电，这些措施会产生进一步的利弊影响：既能为电网提供灵活性，推动能源领域创新，也会带来噪音、污染、温室气体排放，并与能源行业竞争资源。
英文摘要
This report analyses data centre (DC) sustainability and circularity, revealing existing synergies and trade-offs: The PUE is too coarse, mixing cooling and power provisioning. It wrongly attributes server fan consumption and transformation losses to IT energy. It does not measure compute but infrastructure efficiency, which is already outstanding. Compute energy, however, is exploding. Better energy metrics for DCs would thus cover i) compute efficiency, ii) transformation efficiency, and iii) cooling overhead. Trade-offs exist between cooling energy and water as well as on-site and upstream water: Consuming water on-site lowers the cooling energy, which also lowers the water consumed upstream in power generation. For 'wet' electricity, there is little competition: It is worth spending more on-site energy to save both electricity and related upstream water. For 'dry' electricity, there is a trade-off. Waste heat recovery brings energy circularity but has limited uses and is not the same energy quality, a fact not reflected by current metrics. A better metric would consider the avoided energy through heat recovery instead of the amount recovered. Material circularity can be achieved by interpreting the 9R framework in the context of DCs. Circularity-enhancing measures can be categorised into product design, process design and business models, choice of materials, and operating conditions. Together, they have effects across all circularity levels. The relation between DCs and the power grid is complex. Modern DCs present new challenges for the grid. Mitigation includes battery storage and onsite generation. These measures have, in turn, further consequences, both beneficial and detrimental. They can offer grid flexibility as well as innovations in the field of energy. But they also bring noise, pollution, and GHGs, and compete with the energy sector for resources.
Comments94 pages, 12 figures, 4 tables
