Lighthouse Reports, a Dutch non-profit newsroom, lodged a complaint this week, saying the European Commission keeps the public from seeing how much power and water each data center uses.

They classified it under the Aarhus Convention, a binding treaty that grants people the right to access environmental information and to participate in environmental decision-making; the EU joined it in 2005.

The complaint states that the Commission has created a ‘wall of silence’ around the sector, claiming that EU officials intended to prevent access to data on data center performance and have made the little data provided difficult to read.

Moreover, the dispute stems from a 2024 law that prohibits Brussels and the national capitals from sharing data on individual sites. Since the tech companies campaigned for this kind of secrecy on the grounds of their business interests, the Commission is therefore only able to release totals.

The figures show rapid growth: in 2025, Europe’s data centers used 20.7 terawatt-hours of power, the same amount as Croatia, and more than 8 million cubic meters of water, the Commission states.

Also, power consumption increased by 26% and water consumption by 52% in 2024, the figures being based on incomplete data.

Meanwhile, the EU wants to triple its data center capacity to keep up with the US and China, as the AI infrastructure boom drives demand. Local pushback against the sites is growing across Europe as energy bills rise.

Last week, the Commission unveiled a rating label that will grade data centers from A to G on energy efficiency, water use, and clean power from next summer. Lighthouse says the label still hides total use and other figures needed to judge a site’s carbon footprint.

“The choice of ratios over actual consumption figures has no basis in technical constraints, it is a choice that favors the industry over public interest,” the complaint says.

Diego Solier, a conservative MEP working on the EU’s plan to expand digital capacity, said transparency “should be the starting point”.

However, Solier added that firms should not be required to disclose highly sensitive business data. He did not comment on the complaint, which was not yet public.

The Aarhus Convention Compliance Committee will decide in November whether the complaint is admissible, and it could later find that the EU broke the treaty. The Commission did not respond to POLITICO’s request for comment.