Overview
ISO/IEC 30134-2:2016 specifies Power Usage Effectiveness (PUE) as a key performance indicator (KPI) for quantifying electrical energy use within a data centre. The standard defines PUE, the required measurement and calculation methods, measurement categories, reporting constructs, and guidance on correct interpretation. PUE derivatives (partial, designed, interim PUE) and supporting normative annexes address measurement placement, energy supplies and calculation nuances.
Key topics and technical requirements
- Definition and formula: PUE = E_DC / E_IT, where E_DC is total data centre energy consumption and E_IT is IT equipment energy consumption (both measured over the same period). By definition PUE > 1.
- Measurement categories: Three resolution levels are introduced (basic, intermediate, advanced) to match metering quality and measurement placement.
- Measurement and metering: Requirements cover measurement period/frequency, meter selection and placement, and energy measurement practices (see Annex A).
- Handling mixed or multiple energy sources: Calculation guidance for various energy supplies (electrical utility, on-site generation, district utilities) is provided (see Annex B).
- Derivatives: Definitions for pPUE (partial PUE), dPUE (designed PUE), and iPUE (interim PUE) and when to apply them (Annex C and D).
- Reporting and interpretation: Standardized constructs for communicating PUE values, public reporting data elements, trend tracking recommendations, and cautions on interpretation to avoid misuse.
- Scope boundaries and limits: PUE applies to infrastructure energy within the data centre boundary and does not capture IT workload efficiency, productivity, water use, or direct renewable energy accounting.
Practical applications and users
Who benefits:
- Data centre operators and facility managers - for operational benchmarking, identifying efficiency improvement opportunities, and tracking trend data.
- Designers and engineers - to set dPUE targets for new facilities and validate design intent.
- Colocation providers and sustainability teams - for transparent public reporting and client communications.
- Auditors and regulators - to verify consistent measurement and reporting practices.
Practical uses:
- Establish energy-efficiency baselines and measure the impact of cooling, power distribution and UPS changes.
- Compare operational states within the same facility over time (note: the standard advises against using PUE to compare different data centres without context).
- Support investment decisions by quantifying infrastructure losses and prioritizing upgrades.
Related standards
Keywords: ISO/IEC 30134-2, PUE, power usage effectiveness, data centre KPI, data center energy efficiency, PUE measurement, PUE reporting, pPUE, dPUE, iPUE.
Open preview (PDF)Information technology — Data centres — Key performance indicators — Part 2: Power usage effectiveness (PUE)
