# Operate, measure and report

Lesson 4 of [Plan a liquid cooling rollout](https://liquidcooling.fyi/academy/plan-a-liquid-cooling-rollout.md), 15 minutes.

A live system needs steady checks. Measure first, then report. Measure PUE and WUE PUE = total data centre energy / IT equipment energy (ISO/IEC 30134-2). WUE = site water use / IT equipment energy, in litres per kWh (ISO/IEC 30134-9). Example: a site uses 1,000,000 litres of water in a year and its…

The rest of this lesson is for learners enrolled in the course. [See how Plan a liquid cooling rollout works](https://liquidcooling.fyi/academy/plan-a-liquid-cooling-rollout.md).

Also on the [web page](https://liquidcooling.fyi/academy/plan-a-liquid-cooling-rollout/operate-measure-and-report).