The EU Sustainability Rulebook for Data Centres: EED Reporting and What Comes Next

The EU has decided that data centres are too important — and too energy-hungry — to remain unmeasured. The recast Energy Efficiency Directive and its delegated regulation created the first mandatory, EU-wide transparency regime for the sector. For operators and investors in Greece, the obligations are already live, and the direction of travel points towards performance standards, not just reporting.

Who Is Caught — and What Must Be Reported

The 500 kW threshold refers to installed information technology power demand — a level that captures essentially every commercial colocation and hyperscale facility, and many enterprise data centres. Owners and operators must collect and communicate a standardised set of indicators covering energy performance and water footprint: installed power and surface area, energy consumption and its sources, capacity utilisation, waste-heat reuse, water consumption and the four headline ratios (PUE, WUE, ERF, REF).

The mechanics matter: metering and sub-metering must exist at the right boundaries to compute the KPIs defensibly. Facilities designed without adequate metering face genuine retrofit costs — one more reason why compliance belongs in the design phase, a point we develop in our permitting roadmap.

Why This Is Not "Just Reporting"

Three reasons operators should treat the regime as strategic rather than administrative:

• A rating scheme is coming. The delegated regulation exists explicitly to enable a common Union scheme for rating data centre sustainability. Reported performance will eventually be comparable — and marketable, or not.
• Minimum performance standards are on the table. The European Commission has commissioned preparatory work on minimum performance standards for EU data centres, and legal commentators widely expect the regulatory framework to tighten further in coming years.
• Customers and lenders read the same numbers. Hyperscale tenants, ESG-driven investors and financing banks increasingly reference PUE/REF performance in commercial terms and due diligence.

Interaction with the Greek Framework

The EED regime sits alongside national obligations — environmental terms, energy audits under the national implementation of the EED, and, for qualifying entities, the NIS2 cybersecurity framework. For new projects in Greece, the practical approach is to build one compliance architecture from the start: metering design that serves EED KPIs, environmental monitoring that serves the AEPO terms, and documentation that serves both regulators and investors.

What Operators in Greece Should Do Now

• Confirm whether each facility crosses the 500 kW IT-demand threshold — including planned expansions.
• Audit metering against the KPI definitions of Regulation 2024/1364 and close measurement gaps.
• Assign ownership of the annual 15 May reporting cycle and validate data before submission.
• Track waste-heat reuse feasibility: ERF is likely to attract growing regulatory and commercial attention, and Article 12 EED already pushes waste-heat utilisation.
• For projects in development, embed the KPIs in the employer's requirements of the EPC contract.

This article provides general information, verified against the cited sources at the date of publication. It does not constitute legal advice.