Benefits and Limitations of Tapping Into Stored Energy for Datacenters
Datacenter power consumption has a significant impact on both its recurring electricity bill (Op-ex) and one-time construction costs (Cap-ex). Existing work optimizing these costs has relied primarily on throttling de-vices or workload shaping, both with performance degrading implications. In this paper, the authors present a novel knob of energy Buffer (eBuff) available in the form of UPS batteries in datacenters for this cost optimization. Intuitively, eBuff stores energy in UPS batteries during "Valleys" - periods of lower demand, which can be drained during "Peaks" - periods of higher demand. UPS batteries are normally used as a fail-over mechanism to transition to captive power sources upon utility failure. Furthermore, frequent discharges can cause UPS batteries to fail prematurely.