Overview
ISO/IEC 30134-3:2016 defines the Renewable Energy Factor (REF) as a key performance indicator (KPI) for data centres. The standard specifies a clear methodology to calculate, measure, present and interpret the REF, which quantifies the portion of a data centre’s annual energy consumption that is supplied by renewable energy (RE) resources owned and legally controlled by the facility.
Key topics and requirements
- Definition: REF = E_ren / E_DC, where E_ren is the annual renewable energy (kWh) owned and controlled by the data centre and E_DC is the total annual data centre energy consumption (kWh) measured at the data centre boundary. REF ranges from 0.00 to 1.00 (0–100%).
- Renewable energy (RE): Includes energy from renewable sources as defined in the standard; jurisdictional definitions may vary.
- Ownership and control: Only RE for which the data centre owns the legal environmental attributes (e.g., retired Renewable Energy Certificates) counts toward REF. On-site generation counts only if its environmental attributes are retained; sold or traded certificates must be excluded.
- RE certificates: Procurement and retirement of RE certificates (RE certificates) are accepted as RE provided the certificates are retired and documented.
- Measurement:
- REF must be annualized.
- Energy measurements must use watt meters or true kWh meters (true RMS measuring voltage, current and power factor). kVA or apparent power is not acceptable for REF calculations.
- Total data centre energy includes electricity, natural gas and district utilities measured at the facility boundary.
- Reporting requirements: When publishing REF, include data centre boundaries, REF value, measurement period end date (ISO 8601 format), the basis for classifying RE, and the issuing entity/entities for any RE certificates used.
Applications and users
- Who uses it: Data centre managers, sustainability officers, energy procurement teams, colocation providers, corporate reporting and third‑party auditors.
- Practical uses:
- Track and benchmark renewable energy adoption at facility or portfolio level.
- Inform energy procurement strategies (on-site generation vs. certificate purchases).
- Support sustainability disclosure, corporate RE targets and customer selection of data centres.
- Complement other KPIs (e.g., PUE) to provide a holistic view of data centre energy and environmental performance.
Related standards
Keywords: ISO/IEC 30134-3:2016, renewable energy factor, REF, data centre KPI, renewable energy certificates, data center energy, PUE, energy measurement.