Overview
ISO/IEC 13273-1:2015 - Energy efficiency and renewable energy sources: Common international terminology - Part 1: Energy efficiency - is a horizontal terminology standard published by ISO/IEC that defines transverse concepts and agreed definitions in the field of energy efficiency. Its primary purpose is to provide a consistent vocabulary for technical committees preparing standards (in line with IEC Guide 108), and to promote coherence across international documents, guidance and implementations related to energy use, measurement and management.
Key topics
This part focuses on standardized terms and definitions rather than prescriptive procedures. Major topics covered include:
- Fundamental energy concepts: energy, energy carrier, energy source, primary energy, energy conversion, energy storage.
- Energy accounting and flows: final energy, applied energy, system energy loss, recovered energy, lost energy (see Annex B for diagrams and relationships).
- Energy use and intensity metrics: energy use, energy consumption, energy intensity, specific energy consumption.
- Energy management vocabulary: energy management system (EnMS), energy policy, energy objective, energy target, energy action plan, energy management team.
- Energy performance and measurement: energy performance, energy performance indicator (EnPI), energy baseline, measurement and verification (M&V), energy metering, system boundaries.
- Cross-references to existing standards (e.g., ISO 50001) and methodology notes (Annex A: methodology used to develop the vocabulary).
Practical applications
Who uses ISO/IEC 13273-1 and how:
- Standards developers and technical committees - to ensure consistent terminology across international standards and avoid ambiguity.
- Energy managers and consultants - to align internal policies, reporting and EnMS definitions with internationally accepted terms (useful alongside ISO 50001).
- Auditors, M&V professionals and facility managers - to standardize definitions for energy baselines, EnPIs, and measurement practices.
- Policy makers, educators and software/tool developers - to implement consistent domain language in guidance, training and energy management systems or analytics tools.
Related standards
- ISO 50001 (Energy management systems) - many EnMS terms are harmonized with this standard.
- ISO/IEC 13273-2 - companion part covering renewable energy sources terminology.
- IEC Guide 108 - guidance on horizontal standards and their use by technical committees.
ISO/IEC 13273-1:2015 is especially valuable where clarity of terminology affects measurement, reporting and cross-disciplinary standardization in energy efficiency initiatives.