ISO 50001 is the international standard that sets the requirements for an energy management system (EnMS): the policy, roles, measurements and checks through which an organisation continually improves its energy performance. It is voluntary, applies to companies of any sector and size, and does not set consumption levels to be reached: it asks for improvement to be demonstrated over time.
Current edition
The first edition dates from 2011. The current one, ISO 50001:2018, was reviewed and confirmed by ISO in 2024, with an amendment on climate change. In Italy the reference is UNI CEI EN ISO 50001:2018+A1:2024, which differs from the previous version only in that update.
How it is built: the PDCA cycle
The standard follows the Plan-Do-Check-Act model of the other ISO management systems, with which it integrates (ISO 9001 for quality, ISO 14001 for the environment).
| Phase | What is done | What stays in the company |
|---|---|---|
| Plan | Energy policy, analysis of consumption and of significant energy uses, energy baseline and performance indicators (EnPIs), objectives | Action plan with responsibilities and timing |
| Do | Implementation of measures, operational control of plants and processes, staff training | Procedures and records |
| Check | Monitoring of indicators, internal audits | Performance data comparable over time |
| Act | Management review, corrective actions | New objectives |
This is where it differs from an energy audit: the audit photographs consumption and proposes measures, the management system commits top management to deciding, measuring and reviewing them.
Who certifies
The certificate is issued by bodies accredited under the ISO/IEC 17021-1 and ISO 50003 standards. In Italy accreditation is the responsibility of Accredia, which publishes the databases of accredited bodies and certified organisations: that is where the validity of a certificate is checked.
ISO 50001 and the audit obligation
For large enterprises the certified system replaces the four-yearly audit required by Legislative Decree 102/2014, provided that it includes an audit compliant with Annex 2 of the decree. The exemption is not automatic: according to the ministerial clarifications of December 2018 the company must send ENEA three documents.
- A copy of the valid certificate.
- The «system matrix», which shows how the system meets Annex 2 and what the certified boundary is.
- The summary files with the indicators of the main areas of consumption, covering at least 50% of consumption.
Sites outside the certified boundary remain subject to the audit. For energy-intensive companies ISO 50001 is also the alternative to the duty to implement, between one audit and the next, at least one of the measures identified.
The European 85 TJ threshold
Directive (EU) 2023/1791 requires a certified energy management system, by 11 October 2027, for companies with average annual consumption above 85 TJ (about 23.6 GWh) over the previous three years; those with a management system are exempt from the audit required above 10 TJ. As of October 2026 Italy has not completed transposition (reasoned opinion of the European Commission of 1 October 2026): national timing and procedures are not yet defined.
For a business: what to look at
- Who should move first. Large enterprises and energy-intensive companies with consumption close to or above 85 TJ: the system requires measured data, assigned roles and internal checks before the certification body's audit.
- The boundary. Decide straight away which sites fall within the certified boundary: those excluded remain subject to the audit.
- What to prepare. Consumption by carrier and by site, meters on the main uses, a recent audit, a person in charge with a mandate from top management: the 2014 ministerial circular considers this role equivalent, in large organisations, to the energy manager.
- The link with incentives. With a certified system the company can submit projects for white certificates directly to GSE; if the project implements an audit, the decree of 21 July 2025 recognises an extra 2% of savings, up to 40 TOE.
- Typical mistakes. Reducing certification to paperwork, not sending ENEA the system matrix, letting the certificate expire when it is a requirement for an incentive, using indicators that ignore production volumes.
To understand whether and when a management system makes sense in your case, a starting point is the energy audit and efficiency service of IPGS ENERGY: Request a discussion.
Sources
- ISO — ISO 50001:2018, Energy management systems (accessed 10 October 2026)
- UNI — UNI CEI EN ISO 50001:2018+A1:2024 (accessed 10 October 2026)
- Accredia — Sistemi di gestione dell'energia (accessed 10 October 2026)
- Normattiva — Legislative Decree 4 July 2014, no. 102, Article 8 (accessed 10 October 2026)
- MASE — Diagnosi energetiche, with the December 2018 clarifications on ISO 50001 (accessed 10 October 2026)
- EUR-Lex — Directive (EU) 2023/1791 on energy efficiency, Article 11 (accessed 10 October 2026)
- European Commission — October infringements package: key decisions on energy (accessed 10 October 2026)
- GSE — MASE Decree of 21 July 2025 on white certificates (accessed 10 October 2026)
Informational content by IPGS ENERGY. Information is reviewed as of the stated update date and does not replace a contractual, tax or regulatory assessment specific to an individual business.
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