Almost all changes to the CO₂ factors only take effect for footprints from 2026 onwards and therefore do not require a recalculation of previous years. The few exceptions are listed below. The update is in line with the rules for using CO₂ factors for the CO₂ Performance Ladder.

The most important updates for 2026

Below is the list of the most important changes: all factors that have changed by at least 5% plus the change in grey electricity (because this is widely used) and the (few) retroactively changed factors.

• Electricity
  • Grey electricity: -3%
  • Electricity grid mix: -9%
• Fuel and Heat
  • Heat from district heating: +5%
  • Heat and cold from external thermal energy storage (market mix): -9%
  • Green gas (mono-manure digestion | all-purpose digestion | mix): -80% | -30% | -6%
• Refrigerant Emissions
  • R290: from 3 to 0.02 kg/kg (for 2025 and 2026)
  • R600: from 3 to 0.006 kg/kg (for 2025 and 2026)
  • Solvents: from 8 to 0 kg/kg (retroactive for all years)
• Water
  • Wastewater: new factors on CO₂ emission factors for 2024-2025-2026
• Transport (km)
  • Public Transport (pkm): +157%
  • Train (pkm): +900% (but still 20-70 times lower than a car)
  • International Train (pkm): -14%
  • Bus (pkm): +13%
  • Electric Bicycle (km): -33%
  • Electric Moped/Speed ​​Pedelec (km): -15%
  • Electric Car (km): -10%
  • Diesel car (km): +30%
  • 8p minibus (km): +9%
• Transport (fuel)
  • Bio-CNG (kg): -24%
  • HVO (liter): +6%

Location-based factors – 2025 correction

On February 11, it became clear that the location-based factors for footprints for 2025 had not yet been adjusted, still using the factors for 2024. If you had already published a location-based GHG footprint for 2025 before February 11, 2026, it will contain 2024 factors for electricity (and heat). The market-based GHG footprint and the thematic CO₂ footprint were not affected.

Effect on CO₂ Footprint

Most changes only affect footprints for 2026. If you are creating a footprint for 2025 and want to analyze the differences with 2024 and previous years, you will mainly be dealing with the changes to the factors implemented in early 2025, effective from 2025 onwards.

Here you can read the news item about the most important changes in the CO₂ factors for 2025.

Explanation of the changes in the CO₂ factors

Electricity
The emission factors for electricity have been updated based on the (continuously) changing composition of the electricity mix and the increase in the share of green electricity. For gray electricity (i.e., without the influence of green electricity), there is a decrease of 3%. For the grid mix (average electricity in the Netherlands), the CO₂ factor has decreased by 9%. This is due to an increase in the amount of green electricity and because the gray portion of the grid mix has lower CO₂ emissions.

Heating, cooling and green gas
The emission factor for heating supply has increased by 5%.

The CO₂ factor for cooling and heating from an external thermal energy storage (TES) system is determined by the electricity (market mix or green) used by the supplier. For market-mix electricity, the CO₂ factor of the supplied cooling/heating decreases by 9%, while for green electricity it remains zero.

For green gas generation, the CO₂ factors have been recalculated, with the categories shifting slightly. Manure and co-digestion become mono-manure digestion. Organic waste digestion becomes all-biowaste digestion. The CO₂ factors for the digestion techniques are now much closer together than in previous years. Green gas (mix) falls somewhere in between.

Wastewater (retroactive)
Emissiefactoren.nl recently published national wastewater emission factors for 2024-2025-2026. We are adopting these. From the old Environmental Barometer value to 2024, there was a 2% increase. From 2024 to 2025, the factor decreased by 12%, and in 2026, a further 1% decrease was achieved.

Emissions (retroactive)
The CO₂ factor (due to evaporation) of solvents has been retroactively set to zero. This is because CO₂ factors are no longer available. The values ​​for R290 and R600 for 2025 have been corrected on CO₂‑emissiefactoren.nl. This correction was made for the Envirometer. These also apply to 2026.

Transport
Looking at fuels (in liter or kg) only biofuels have significant changes in the emission factors: bioethanol (-3%), bio-CNG (-24%) and HVO biodiesel (+6%) due to changes in the production chains.

There are new CO₂ factors per vehicle kilometer. Explanation of the major changes:

• Public transport and trains have changed significantly. This is because the Dutch Railways (NS) has a new energy contract and trains now run on European green electricity instead of Dutch green electricity. Because CO₂ emission factors only include Dutch green electricity, train kilometers are now calculated using gray electricity. Per passenger kilometer, the CO₂ factors for trains and public transport in general are still very small compared to car kilometers; but expressed as a percentage, the CO₂ factors are increasing very sharply.
• For entries on cars expressed in km, only diesel cars have seen a significant increase in the CO₂ factor. This is mainly because the average diesel car is much heavier than a few years ago.

The changes are all in line with CO₂‑emissiefactoren.nl: https://www.co2emissiefactoren.nl. You can find the changes there in the “CO₂emissiefactoren.nl changes overview”: https://co2emissiefactoren.nl/downloads/ .