Energy measurement questions for AI and data-center procurement
Suggested questions for buyers of colocation, cloud and GPU capacity, so supplier energy figures can be compared like for like.
Ask for the boundary first
- At which meter point was each figure measured: chip, board, system or facility?
- Over what period, and for what workload or task set?
- Was the figure measured, estimated or taken from a specification sheet?
Measured versus rated power
Rated figures such as thermal design power and power-supply ratings are not measurements. MLPerf Power requires measured full-system power over a window of at least 60 seconds and rejects rated power and PUE as substitutes (Tschand et al., MLPerf Power). Ask for measured values and the instrument used.
Facility ratios
- PUE with its ISO/IEC 30134-2 measurement category and a full twelve-month period (ISO/IEC 30134-2:2026)
- WUE with its period and water sources
- Whether any part of the facility is left out; if so, the figure is a partial PUE
EU data the supplier may already hold
Operators of EU data centers of at least 500 kW report under Delegated Regulation (EU) 2024/1364, and the EU rating scheme adds A-to-G grades for energy and water. See the EU rating scheme and the reporting crosswalk.
A copy-ready question list
| Topic | Suggested question |
|---|---|
| Boundary | State the meter point and what it includes and excludes. |
| Method | Is each figure Measured or Estimated? Name the instrument or model. |
| Period | Give the period and how many hours or tasks it covers. |
| Useful work | How many completed tasks or decisions did the energy produce? |
| Overhead | Is facility overhead included? Give PUE with its period. |
| Change | How will you report changes in hardware, firmware or software that affect energy? |
Red flags
- A device figure compared with a facility figure
- A best month presented as an annual figure
- Specification-sheet power presented as measured
- Adjectives without numbers; see how energy metrics get gamed
Not legal advice
These are suggested questions, not contract terms and not a compliance test. This guide is general information, not legal advice. Check the current text of each rule, and take advice for your situation.
Questions
Can AAERL check supplier figures?
A Joule Ledger Assessment measures one system at declared meter points and grades the result Witnessed. It does not certify a supplier.
Sources
Keep reading
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What to ask suppliers of colocation, cloud and GPU capacity about energy: boundaries, measured vs rated power, PUE periods, EU data, and red flags.