ISO 50001:2018Energy management systems
ISO 50001 sets out how an organization measures the energy it uses, finds where most of it goes and reduces it step by step. It covers electricity, fuel, gas, steam and any other energy type, and it does not set a saving you must reach: you set your own targets and show with data that energy performance is improving. The current edition is ISO 50001:2018.
01At a glance
- Standard
- ISO 50001:2018
- Subject
- Energy management systems
- Certificate
- Issued by AQC Group. Valid for three years, with a surveillance audit each year.
- Sectors
- Manufacturing, Food industry
- Facts checked
- 9 October 2026, against iso.org
Who it is for
- Plants where energy is a major cost: furnaces, kilns, boilers, compressors
- Food and beverage plants running refrigeration, ovens and steam
- Sites that generate their own power from diesel or gas
- Data centres and other sites that run day and night
- Large buildings with heavy cooling and ventilation loads
- Companies whose clients or lenders ask for evidence of energy management
02What you gain
What certification to ISO 50001 gives you
Lower energy bills, where the savings are real
Measurement often shows loads running when they are not needed, leaks and poor settings. Fixing them reduces what you pay for electricity and fuel. The size of the saving depends on your site and cannot be promised in advance.
Know where the energy goes
An energy review shows which equipment and processes use the most. Decisions about maintenance and investment can then be made on figures.
Meet client, tender and lender requirements
Some clients, tenders and financing bodies ask for evidence of energy management. Certification to ISO 50001 provides it.
Savings that last
Results are tracked against a baseline and reviewed by management, so a saving that slips is noticed. A one-off project can fade when nobody is watching the figures.
Lower emissions from energy
Using less fuel and electricity lowers the greenhouse gas emissions that come from them. This supports ISO 14001 objectives and answers customers who ask for emissions data.
03What it asks of you
What ISO 50001 asks you to have in place
In plain terms and in our words, not the standard's. The standard itself is the authority, and you will need a copy.
Scope, boundaries and context
Decide which sites, buildings and processes the system covers. Every type of energy used inside that boundary is included. Note the issues that affect your energy performance, such as energy prices, reliability of supply and production plans.
Leadership and the energy team
Top management issues an energy policy, forms an energy management team and gives it time, authority and budget. It approves the targets and action plans, sees that they are carried out and reviews the results.
The energy review
Analyse your energy use and consumption from bills and meter data. Identify the significant energy uses: the equipment, systems or processes that use the most or offer the most room to improve. For each one, find what drives its consumption, such as output, weather or operating hours, and list the opportunities to improve. Repeat the review at set intervals and after major changes.
Indicators and baselines
Choose energy performance indicators that suit your operation, such as energy per tonne produced or per square metre. Set a baseline from a past period to compare against. Adjust the comparison for the things that drive consumption, so that a busy month is not mistaken for waste.
Objectives, targets and action plans
Set energy objectives and targets. Write action plans that say what will be done, by whom, by when, with what resources and how the result will be verified. Plan how you collect energy data: what is measured, how often and with which meters.
Running, designing and buying
Operate and maintain the significant energy uses within set criteria, such as temperature set points, pressure settings and shutdown routines, and train the people who run them. Consider energy performance when you design or modify plant and buildings. When you buy equipment or services that affect a significant energy use, make energy performance one of the criteria and tell suppliers so.
Monitoring and measurement
Follow your indicators against the baseline, investigate significant deviations and keep the records. Make sure the meters and data you rely on are accurate enough for the purpose. Evaluate whether you meet the legal and other requirements on energy that apply to you.
Audit, review and improvement
Run internal audits and management reviews, and correct nonconformities at the cause. Having a system is not enough: the standard expects you to show, with data, that energy performance is improving against your baseline.
04The audit
How certification to ISO 50001 works
Application and quotation
You tell us your scope, sites and headcount. We quote the audit days the standard's rules require.
Stage 1 audit
A review of your documented system and your readiness. You get a list of anything to settle before stage 2.
Stage 2 audit
The auditor follows your processes on site and samples records, to see that the system is in use and works.
Decision
Nonconformities are answered, the file is reviewed independently of the audit team, and AQC Group issues the certificate.
Surveillance and recertification
A shorter audit in each of the next two years, then a full recertification audit in the third.
What the auditor looks at
- The energy review: the data behind it and how the significant energy uses were chosen
- Indicators and baselines, and whether they are adjusted for the factors that drive consumption
- Evidence in your own data that energy performance has improved
- Operating controls and maintenance on the significant energy uses, seen on site
- The plan for collecting energy data, the meters and the accuracy of the figures
- How energy performance is taken into account in design projects and purchasing
What affects audit time
- Annual energy consumption and the number of energy types in use
- The number of significant energy uses
- The number of people whose work affects energy performance, which can be fewer than the total headcount
- The number of sites, and whether ISO 14001 or ISO 9001 is audited in the same visit
05Often combined with
Standards audited alongside ISO 50001
Standards that share a structure can be audited together, in one visit and against one set of documents.
06Questions
Questions about ISO 50001
What is the difference between ISO 50001 and ISO 14001?
ISO 14001 covers all the ways an organization affects the environment, with energy as one of them. ISO 50001 covers energy only and goes further into it. It asks for an energy review, a baseline, indicators and a plan for collecting data, and it expects evidence that energy performance is improving.
The two share the same structure and can be audited together. A plant whose main environmental effect and main cost is energy sometimes starts with ISO 50001.
Does ISO 50001 require a set percentage of energy saving?
No. The standard does not set a figure. You set your own targets from your energy review. What it does expect is evidence that energy performance is improving over time against your baseline, and an auditor will ask to see it.
Improvement can be shown in total consumption or in consumption per unit of output. A plant that produces more may use more energy in total and still have improved.
Is an energy audit the same as ISO 50001?
No. An energy audit is a one-time study of where energy is used and what could be saved. ISO 50001 is a management system that keeps working: it repeats the review, tracks indicators, assigns actions and reports to management.
An energy audit is a good input to the energy review the standard asks for. If you have had one in recent years, keep the report.
Do we need a meter on every machine?
No. The standard asks you to measure the key characteristics of your significant energy uses and to plan how you collect the data. It does not set a number of meters. You can start with utility bills, the main meter, fuel delivery records and a few temporary measurements, and add meters where the review shows they are worth the cost.
What the auditor needs to see is that your figures are good enough to support the conclusions you draw from them.
We generate our own power. Does ISO 50001 still apply?
Yes. The standard covers every type of energy used inside the boundary you set. That includes diesel or gas burned in generators as well as electricity bought from a grid. Fuel delivered and electricity produced can both be measured, and the generators themselves may turn out to be a significant energy use.
Is ISO 50001:2018 still the current edition?
Yes. ISO reviewed the standard and confirmed it in 2024, and ISO's catalogue showed no revision under way when we checked on 9 October 2026. A short amendment in 2024 added that an organization considers whether climate change is a relevant issue for its system.
There is no transition to plan for.
Ask about ISO 50001 for your organization.
Tell us your scope, your sites and how many people work in them. We will tell you what the audit involves.