Cooling

Efficiency metrics

PUE is total facility energy over IT energy. Partial PUE applies the ratio to one subsystem. WUE is water per IT energy. ERF is the share of energy reused elsewhere. TUE also counts the fans and pumps inside the IT equipment that PUE hides.

Source: https://baltimoreaircoil.com/articles/energy-water-efficiency-data-center-metrics Checked 2026-09-18

the topic source was opened on 2026-09-18 and defines PUE, pPUE, WUE and TUE; it does not define ERF, which is instead defined on the heat-reuse topic's source