Setting up an ISO 50001 energy management system: the steps

An energy management system is not built by writing procedures. It is built by answering, in order, four questions: where does the energy go, what am I comparing myself against, how do I measure, and who decides. Everything else — documentation, internal audits, management review — rests on those answers.

Here is the method, step by step, as structured by NF EN ISO 50001 in its 2018 version.

Step 1 — Frame the scope and the ownership

Two decisions come before anything else.

Scope. A pilot site or all installations? One legal entity or a group? The scope and boundaries will appear on the certificate, and they determine the workload. A pilot site allows fast learning; a full scope avoids having to redo everything later. If the approach answers a regulatory obligation, the certified scope must cover the scope of that obligation.

Ownership. You need an identified operational owner and a sponsor in top management. That is no formality: the available work converges on management support as the decisive success factor. A study by Heidi Fuchs, Arian Aghajanzadeh and Peter Therkelsen published in 2020 in Energy Policy, based on 72 case studies of certified organisations, ranks securing and sustaining that support at the top of the keys to success, and the absence of an energy-management culture at the top of the obstacles (see the study).

At this stage, also identify internal and external issues related to energy — supply contracts, production constraints, customer requirements, applicable regulatory obligations — and the interested parties.

Step 2 — The energy review

This is the foundation. It is built in four moves.

Gather the real data. Invoices for every energy purchased over at least twelve rolling months, and preferably three years: electricity, gas, heat network, steam, heating oil, fuels, vehicle fuel. Sub-metering readings where they exist. And, over the same period, activity data — production, floor area, volumes transported, running hours — because those are what will allow normalisation.

Reconstruct the breakdown. Where does the energy go? By site, by workshop, by utility (compressed air, refrigeration, steam, heating, ventilation, lighting), by process. An approximate but documented breakdown beats no breakdown at all. The standard does not require immediate exhaustive metering: it requires an explicit method and a plan to improve measurement.

Designate the significant energy uses. The criterion combines weight in total consumption and improvement potential. A modest but highly improvable use may be significant; a heavy but already optimised one may not be. The choice is justified in writing — it is among the first things an auditor looks at.

Identify the opportunities. Settings and operating actions, maintenance actions, investment actions, ranked by expected gain, cost and lead time. This table will feed the action plans and be examined in the management review.

A classic mistake: outsourcing the entire energy review and filing the report. The report is not the system. What counts is that the organisation owns the data, updates it and uses it to decide.

Step 3 — Baseline and indicators

The energy baseline is the quantified snapshot against which all future performance will be compared. The period chosen must be representative of the activity, long enough to smooth out one-offs, and documented as to the conditions under which it was observed.

The energy performance indicators raise the most technical question of the whole exercise: normalise by what?

• In industry, consumption per unit produced — kWh per tonne, per part, per linear metre. The production mix still has to be stable enough for the indicator to stay readable.
• In commercial buildings, consumption per square metre corrected for weather, so a mild winter is not read as a performance.
• In logistics, consumption per volume transported or per distance.

Two rules avoid most of the trouble. First, an indicator must be calculable from the data you actually collect, not from the data you wish you had: two indicators fed every month beat ten theoretical ones. Second, the rule for adjusting the baseline — on a major change of process, installation or scope — must be written in advance, never improvised on the day the comparison turns awkward.

Step 4 — Objectives and action plans

Objectives follow from the opportunities identified, not from a headline ambition. Each action plan states what is done, by whom, with what resources, by when, and how the result will be verified — that last column being the one most often forgotten.

A balanced first action plan typically has three lines: a settings or operating action requiring no investment, a maintenance action, and a costed investment action. The first delivers a quick gain that gives the approach internal credibility; the third puts the subject on the management table.

Step 5 — Run the system day to day

Four clauses of the standard play out here.

Competence and awareness. People whose work affects energy performance must be competent and aware of their influence. An operator who knows why they do not leave a compressor idling is worth more than a posted instruction.

Operational control. Operating instructions, settings, running ranges, maintenance of significant uses. This is the base of the no-investment gains.

Procurement. The standard requires energy performance to be built into purchases of energy, equipment and services. An energy criterion in a specification commits the organisation for the whole service life of the equipment.

Design. New installations, major modifications and refurbishments must consider energy performance from the design stage. It is the most powerful lever and the most often neglected.

These last two points are what separate a serious approach from a cosmetic one — and the auditor knows it.

Step 6 — Check: internal audit and management review

The internal audit verifies that the system conforms to the standard and is effectively implemented. It must be run by auditors who are competent and objective towards the activity audited: an energy manager does not audit their own system.

The management review is where top management decides. It examines indicator performance against the baseline, progress of action plans, deviations and their causes, and the resources needed. A management review that merely records figures without arbitrating does not fulfil its function — and it shows.

At this stage, also assess compliance with applicable legal requirements on energy, including reporting obligations.

Step 7 — The certification audit

Certification is issued by an accredited third-party certification body — in France by Cofrac for this type of scheme.

The initial audit runs in two stages. Stage 1 verifies that the system exists and is ready: scope, energy review, baseline, indicators, planning, internal audit and management review completed. It often produces a list of points to consolidate. Stage 2, on site, verifies real implementation: interviews with operators, examination of records, consistency between what is written and what is done.

Findings are graded: a major non-conformity blocks certification until resolved, a minor one calls for an action plan usually verified at the next audit. The certificate covers three years, with annual surveillance audits and renewal at the end of the cycle. The detailed process and the expected evidence are described in our article on the ISO 50001 certification audit.

What a well-run system produces

The gain is not merely documentary. A study by Patrick Fitzgerald, Peter Therkelsen, Paul Shaeffer and Prakash Rao published in 2023 in Sustainable Energy Technologies and Assessments analyses verified data from 83 ISO 50001-certified industrial sites and measures an annual energy performance improvement of around 4.1% in the first year, still around 3.4% twelve years after implementation (see the study). The striking result is not the size of the gain but its persistence: exactly what a permanent framework adds over a one-off expert engagement.

Going further

The regulatory framework that sometimes makes this approach mandatory is detailed in our article on the 2.75 and 23.6 GWh thresholds, and the trade-off with the energy audit in ISO 50001 or an NF EN 16247 energy audit. If you are starting from an existing system, see ISO 50001 and ISO 14001: two standards, two logics and the sheet on ISO 14001 certification.

Take action

Start with step 2 using the data you already have: twelve months of invoices are enough to launch a useful energy review, without waiting for a single meter to be installed. Appoint an owner and a management sponsor in the same movement — without them, none of the following steps will hold. The full scheme sheet, with the steps and frequently asked questions, is here: ISO 50001 certification.