Data centres in Germany consume significant amounts of electricity and water. According to data from the digital association Bitkom, their electricity consumption reaches almost four per cent of the country's total consumption. Despite this, many companies managing these centres hide consumption data, which prompted the German public broadcaster ARD to send queries to more than 30 companies.
The Energy Efficiency Act in Germany obliges operators of larger data centres to publish data on electricity and water consumption. However, more than half of the 30 largest operators in the country are likely not fulfilling this legal obligation. Among them are market leaders such as Equinix, NTT and CloudHQ, which have not provided the requested information. Some operators refuse to publish data, citing trade secrets, a position disputed by experts.
Bernhard Wegener, a professor of public and European law at Friedrich-Alexander University in Erlangen and Nuremberg, believes that the practice of hiding data is not in line with the Energy Efficiency Act. A similar view is held by Julian Bothe, an expert in artificial intelligence and sustainability from the organisation AlgorithmWatch, who criticises the lack of transparency by operators despite the current crisis in energy prices and water availability. According to an expert opinion commissioned by AlgorithmWatch, consumption data rarely merits protection as a trade secret.
The German government plans to double data centre capacities by 2030. Currently, there are around 100 facilities with a connected load of five megawatts or more. The Federal Office for Economic Affairs and Export Control is responsible for collecting consumption data and states that there are no exceptions due to business and operational secrets. The Federal Ministry of Economics confirmed that companies are obliged to publish data, but the Ministry considers that additional controls are not necessary as it is a generally applicable legal obligation. Legal expert Wegener, however, assesses this approach as problematic from the perspective of the rule of law.
The National Data Centre Register (RZReg) was published in August, but only about one in four of the 100 largest data centres in Germany is recorded in the register. Many operators submitted data to the ministry but did not agree to its publication in the register. The German Data Centre Association (GDA), which organises Open Data Centre Days in early November, emphasises that no conclusion can be drawn that operators are violating legal obligations based solely on unanswered journalistic queries. The GDA also highlights that data centres are exceptionally sensitive facilities where security is the top priority.
Examples from practice show different approaches by operators. Equinix claims it fulfils all legal obligations and that publishing data on individual centres could reveal business plans to competitors. On the other hand, NTT provided data on total energy consumption for 2025, which corresponds to the annual consumption of approximately 450,000 households, but did not provide detailed data for individual centres, citing the EU Energy Efficiency Directive. CloudHQ did not provide the requested data nor respond to allegations of legal violations. A journalistic investigation by SWR showed that most operators do not publish the requested indicators on their websites.
The Open Data Centre Days, organised by the GDA, aim to allow the public insight behind the scenes and increase transparency in a sector that significantly impacts resource consumption. However, existing challenges in data publication and differing operator positions indicate a need for additional oversight and clearer rules in the future.
