BRUSSELS — A day after researchers published detailed calculations showing that AI data centres are measurably raising ambient temperatures in surrounding urban areas, European Commission environment and digital officials on Sunday signalled that mandatory thermal impact reporting requirements for large-scale data centre operators could be incorporated into the forthcoming revision of the EU Energy Efficiency Directive. The research, which circulated widely on Saturday, provided city-level heat contribution figures that regulators said could no longer be treated as externalities.

The Commission's directorate-general for energy confirmed it had received the study and was in preliminary discussions with member states including Germany, the Netherlands, and Ireland — three of Europe's most data-centre-dense jurisdictions — about establishing standardised reporting frameworks. Officials said the goal would be to require operators above a defined megawatt threshold to disclose waste heat output, local air temperature impact assessments, and cooling water consumption on an annual basis.

Industry groups representing hyperscale operators including Microsoft, Google, and Amazon Web Services pushed back cautiously, acknowledging the scientific findings while arguing that existing voluntary sustainability disclosures and the EU's own Green Deal data centre commitments already addressed thermal management. A joint statement from the European Data Centre Association noted that many newer facilities already deploy waste heat recovery systems that feed district heating networks, citing deployments in Stockholm and Helsinki as models.

Urban planners and climate scientists welcomed the regulatory momentum. Dr. Annelies van der Berg of Wageningen University, whose team contributed to the heat impact modelling cited in the study, said on Sunday that the findings underscore the need to factor data centre placement into city climate adaptation plans. 'The thermal footprint is localised and significant, particularly in densely built neighbourhoods within two kilometres of large facilities,' she said in a statement to European press.

Analysts tracking EU digital infrastructure policy said the development adds a new compliance dimension for operators already navigating the EU AI Act and data sovereignty requirements. 'Thermal disclosure could become a site-permitting condition within 18 months if the Commission moves quickly,' said one Brussels-based regulatory consultant. The Commission is expected to release a formal consultation document on data centre sustainability metrics before the end of Q2 2026.