EU accused of hiding data centre energy and water data as AI build-out accelerates

Lighthouse Reports lodged the complaint with the Aarhus Convention Compliance Committee, a body that meets quarterly. It will first decide in November whether the submission is admissible. POLITICO first reported the filing. Lighthouse Reports is a Netherlands-based non-profit that runs cross-border investigations. It argues the Commission has built a "wall of silence" around how much power and water Europe's data centres actually use. The timing is awkward.

The European Union has publicly declared a target of tripling data-centre capacity in the coming years to keep pace with the United States and China. Last week the Commission presented a new transparency label meant to steer investment towards greener facilities, and minimum performance standards are expected to follow. Lighthouse says the label does not fix the underlying problem. It grades operators on ratios rather than disclosing actual consumption figures. That is the core of the dispute.

What the complaint says

The legal filing focuses on the Energy Efficiency Directive, a 2023 law that requires all data centre operators in the EU to report a set of power and water metrics. Those metrics include total energy consumption, the amount and type of renewable energy used, waste heat reused, average waste heat temperature, cooling degree days and cooling system setpoints, the types of refrigerants used in the computer room floor, and total and potable water input. Reporters from Lighthouse and partner newsrooms filed freedom of information requests in all 27 member states, plus a sample request to the Commission itself, which holds the full dataset.

From the outset in October 2025, the newsroom says it faced non-disclosure. Ten countries told reporters they did not hold the figures relating to their own data centres. According to the investigation, that implies they had no oversight of how those buildings affect national energy efficiency goals and net zero commitments. A half-dozen more argued for blanket confidentiality to protect commercial interests. Appeals and reviews largely failed. The complaint is filed under the Aarhus Convention, a legally binding treaty that gives the public rights to information and participation in environmental decision-making. It is the first of its kind the newsroom is aware of by an investigative outlet.

The Commission's own published figures show Europe's data centres used 20.7 terawatt-hours of electricity in 2025, about as much as the whole of Croatia, and more than 8 million cubic metres of water. That is a 26% rise in electricity use and a 52% rise in water use from 2024. But the totals come from incomplete data collected by the Commission, and they are published only in aggregate. A 2024 law banned Brussels and EU capitals from disclosing "all information and key performance indicators for individual data centers" after lobbying from tech companies, which cited commercial interests.

"The Commission sits at the top of an edifice of non-disclosure encompassing the vast majority of the EU," the Lighthouse complaint says. "Siding with commercial secrecy over the public's right to know erodes legitimacy and damages trust further."

The Commission did not respond to POLITICO's request for comment. Diego Solier, a conservative member of the European Parliament working on the EU's push to boost digital capacity, told POLITICO that expansion must be accompanied by reliable information for citizens and policymakers. He added that transparency must be proportionate and should not force companies to disclose genuinely commercially sensitive information. He did not comment on the complaint, which was not public at the time.

The EU's energy chief, Dan Jørgensen, told POLITICO in an interview that big power consumers risk undermining the bloc's own climate targets if they are not held in line with overall objectives. The new rating label will require operators to grade energy efficiency, water usage and clean power uptake from A to G starting next summer.

The row lands in a wider fight over who pays for and who sees the environmental cost of the AI boom. Public opposition to power-hungry AI data centres is growing across Europe while energy prices rise, POLITICO notes. Lighthouse argues the choice of ratios over actual consumption figures "has no basis in technical constraints" and favours industry over public interest.

The AI jobs debate runs in parallel

The same build-out is being scrutinised for its effect on labour markets, though the dossier for that story is thinner than the data centre dispute. Recent headlines assembled for context point to a widening argument rather than settled numbers. CNN reported on 29 September that AI could force 11 million US workers into new careers by 2035. The Harvard Gazette asked the same day why AI has not triggered mass layoffs yet. PwC published its Global Workforce Hopes and Fears Survey 2026 on 29 September. Personnel Today reported the same day that the UK needs a contingency plan for mass job losses caused by AI.

Those items are context, not evidence we can lean on here. What is documented is the infrastructure demand driving the argument: the Commission's own 20.7 TWh figure for 2025, the 26% annual increase, and the stated EU goal of tripling capacity. Data centres are the physical layer of the AI economy, and the fight over their consumption is a fight over what the public can verify.

Elsewhere in the dossier

BloombergNEF reported on 30 September that global sales of medium- and heavy-duty electric trucks reached a record 158,000 units in the first half of 2026, up 75% year on year, with more than nine in ten sold in China. Electric trucks now account for about 20% of total truck sales globally and 5.5% in Europe, according to BNEF, which also noted that Tesla's Semi is priced between $250,000 and $300,000 per vehicle. That is a demand signal for grid and charging infrastructure, the same infrastructure the data centre complaint is about, though BNEF does not connect the two.

Andreessen Horowitz published the second edition of its State of Markets on 30 September, arguing that hardware and infrastructure have replaced software as the centre of the market's attention, with tech contributing roughly 76% of the S&P 500's total earnings growth in 2026 as of late August. The firm's PDF version of the report was posted the same day. Neither document addresses the EU transparency dispute directly, but both describe the capital flows behind the build-out that Lighthouse is trying to make visible.

Two other sources in the dossier, a Wikipedia entry on organised markets and a blog post about developer marketing, do not bear on the labour or energy questions and are not used here.

The immediate next step is procedural. The Aarhus Convention Compliance Committee meets in November to decide whether the Lighthouse complaint is admissible, POLITICO reported. If it is, the committee could subsequently find the EU in breach of its obligations under a treaty the bloc has been party to since 2005. Until then, the aggregate figures remain the only public window into a sector the EU wants to expand sharply, and the complaint's central claim is that the window is deliberately too small to see through.