Utrecht University reports that its modelled biodiversity footprint decreased in 2025, mainly because of changes in energy use. Its technical report compares a 2025 result of 1,529 PDF hectare-years with a recalculated 2024 baseline of 1,950.

The university announced the result on 29 October 2026. The report's heading describes the decline as 21 per cent, while its accompanying text says 22 per cent. The two published totals imply a reduction of about 21.6 per cent.

What was measured

The footprint estimates the potential decline in biodiversity associated with university activities. Its unit, PDF hectare-year, combines the potentially disappeared fraction of species with area and time. It is a modelled impact indicator, not a count of species that the university has caused to disappear.

The assessment covers five areas: the built environment, food and catering, the natural environment, digital services and procurement. It includes supply-chain effects outside the Netherlands as well as impacts closer to Utrecht, such as land and water use, pollution and fertilisers.

The model uses more than 200 processes and the ReCiPe 2016 Endpoint method. Non-university-owned buildings and underground infrastructure are outside its scope.

A revised baseline and the 2030 target

The original 2024 assessment produced a total of 2,244. For the new comparison, the researchers restructured the model, checked assumptions and incorporated better data. That reduced the 2024 baseline by 13 per cent to 1,950.

The original 2,244 and the 2025 result are therefore not a like-for-like pair. Calculating a 32 per cent decline from those figures would overstate the measured year-on-year change.

Utrecht University's current biodiversity page sets a 35 per cent reduction target for 2030 compared with 2024. The annual change reported here uses the recalculated 2024 baseline.

Where the reduction came from

The news release says energy delivered the largest reduction. The university minimised summer use of its combined heat and power plant and introduced more efficient cooling. The technical report says the overall decline was driven largely by the built environment and food and catering.

Energy operations account for 91 per cent of the modelled impact in the built-environment category. The report attributes the decrease mainly to less natural gas used for university energy production and a shift towards purchased electricity, most of it wind power.

Food, cocoa and uncertainty

The report estimates that cocoa accounts for 38 per cent of the food-and-catering footprint and coffee for 18 per cent. Utrecht University says it is working with caterers Maas, Eurest and Vineyard on plant-based milk alternatives and more sustainable chocolate and snacks.

Those estimates have limits. The researchers did not have specific sourcing locations for food products and used global or regional datasets. They rate uncertainty in food and catering as high. Uncertainty is also high for the natural-environment category and very high for procurement, where some physical data were unavailable and spending-based estimates or representative products were used.

The university says further reductions could come from more renewable energy, less reliance on natural gas, heat storage and more sustainable buildings and installations. These are proposed routes for future improvement, not reductions already measured in the 2025 result.

Why the annual measure matters

Utrecht University plans to repeat and publish the assessment each year. That creates a way to track changes, but the rebaselining also shows why totals depend on data quality, scope and modelling choices.

The report says future assessments need better information on food origins, procurement quantities, land use and construction materials. It also says the current model can miss the benefits of campus measures such as pollinator-friendly flower beds because the available land-use data are not detailed enough.