What Is ISO 50100:2026? Decarbonization in Energy Management Systems

ISO 50100:2026 is an international standard that sets out how organizations should reduce the greenhouse gas emissions arising from their energy use and how they should prove that reduction. Published in March 2026, the standard starts from a simple premise: using less energy does not always mean emitting less carbon.

What Does ISO 50100 Change?

Imagine a factory that cuts its emissions per product by 10% while increasing its output by 20% over the same period. Per product, the picture looks positive, but total emissions have risen by about 8%. This is exactly where ISO 50100 comes in, requiring a demonstrated absolute emission reduction in line with targets. In other words, improvement per unit is not enough on its own; total emissions must genuinely fall too.

The standard focuses on energy-related greenhouse gas emissions:

• Scope 1: Fuels burned at the company's own sites and in its own vehicles. For example, natural gas used in a boiler or diesel in company shuttles.
• Scope 2: Emissions from purchased energy. For example, electricity the factory takes from the grid.

How Does It Differ from ISO 50001?

The first question many people ask is whether ISO 50100 replaces ISO 50001. It does not; the two standards complement each other. ISO 50001 focuses on managing energy performance, while ISO 50100 looks at how that work translates into emissions.

For example, when a facility keeps consuming the same amount of energy but switches to a lower-carbon energy source, its emissions can fall even though its energy consumption stays the same. Organizations with an ISO 50001 system can therefore use ISO 50100 alongside their existing structure.

What Does the Standard Expect from Organizations?

1. Set boundaries: Decide which sites and activities are included in the plan.
2. Choose a base year: Define the starting period against which progress will be compared.
3. Calculate emissions: Use energy consumption data and emission factors for a transparent, repeatable calculation.
4. Set absolute targets: Define interim and long-term reduction targets in tonnes of CO₂ equivalent.
5. Prepare a decarbonization plan: Plan measures such as energy efficiency, renewable energy and electrification, with owners and a timeline.
6. Monitor and report: Manage deviations and report results together with supporting evidence.

Who Is ISO 50100 Suitable For?

ISO 50100 is a standard that organizations of any sector and size can apply voluntarily. That said, it offers a particularly meaningful framework for three groups:

• Companies that have made net zero or emission reduction commitments
• Industrial organizations with high energy costs and emissions
• Exporters receiving requests for verifiable reduction data from customers or investors

In short, ISO 50100 changes the question: what matters now is not only how much energy you save, but whether you can prove that your total emissions have really fallen. To assess your energy management system and decarbonization targets together, get in touch with our experts.