Overview
ISO 50002-3:2025 - Energy audits - Part 3 provides practical guidance for conducting energy audits of industrial and commercial processes using ISO 50002-1. It is a supplementary document intended to be used alongside the Part 1 general requirements. The standard covers how to define audit scope and boundaries for processes, collect and verify process energy data, plan measurements, perform on-site activities, analyse energy performance and report findings tailored to process environments.
Key topics and requirements
- Scope and boundaries: Guidance on defining process boundaries, inclusion of utilities and outsourced services, and coordination when buildings are also in scope.
- Planning and roles: Clarification of relationships among audit client, auditee and operators where ownership, operation and maintenance can be split.
- Data collection: Recommended types of data to collect (site, utility, production process, energy sources), verification, plausibility checks and handling of missing data. (See Annex A for examples.)
- Measurement plan: How to review existing data, identify measurement needs, develop measurement plans and perform preliminary data analysis to determine significant energy uses (SEUs) and relevant energy performance indicators (EnPIs).
- Site work and analysis: Guidance on site visits, management of fieldwork, energy balance estimation, identification and evaluation of energy performance improvement opportunities.
- Reporting and meetings: Requirements for content of audit reports and conduct of opening/closing meetings.
- Competence: Statements on the competence requirements for the energy auditor.
- Informative annexes: Includes guidance on data collection (Annex A), measurement quality (Annex B) and representative sampling for multi-site organizations (Annex C).
Practical applications and users
Who benefits:
- Energy auditors and consultants conducting process-focused energy audits
- Industrial facility engineers and operations managers (e.g., manufacturing lines, utilities, steam systems, dryers, furnaces)
- Organisations implementing or integrating energy audits into an Energy Management System (EnMS)
- Multi-site organizations seeking representative sampling approaches
Practical uses:
- Structuring process energy audits to identify SEUs and EnPIs
- Preparing measurement plans and data verification procedures specific to process equipment and operational conditions
- Evaluating energy performance improvement opportunities (process optimization, utility interaction, changeover impacts)
Related standards
- ISO 50002-1 - Energy audits: general requirements with guidance for use (normative reference)
- ISO 50002-2 - Guidance for building-related energy audits (use when buildings are included in the audit scope)
Keywords: ISO 50002-3, energy audit, processes, energy performance, energy auditor, EnMS, measurement plan, data collection, SEU, EnPI.
