The European Commission has introduced a common A-to-G sustainability rating system for data centers, requiring covered facilities to publish electronic labels showing their energy and water efficiency.
The delegated regulation, published on September 21, will rate facilities using Power Usage Effectiveness and Water Usage Effectiveness. The first labels are scheduled to be generated by the European data center database by August 15, 2027, with updated labels issued annually.
The labels will be publicly available electronically and issued in all official languages of the European Union.
Labels Will Grade Energy and Water Efficiency
The new scheme assigns separate A-to-G classes for energy and water performance. Energy ratings are based on PUE, which compares a facility’s total energy consumption with the electricity delivered to its IT equipment. Water ratings use WUE, measuring annual water consumption against IT equipment energy use.
| Rating | Energy efficiency — PUE | Water efficiency — WUE |
|---|---|---|
| A | 1.15 or lower | 0.10 or lower |
| B | Above 1.15 to 1.25 | Above 0.10 to 0.20 |
| C | Above 1.25 to 1.35 | Above 0.20 to 0.40 |
| D | Above 1.35 to 1.50 | Above 0.40 to 0.60 |
| E | Above 1.50 to 1.70 | Above 0.60 to 0.80 |
| F | Above 1.70 to 1.90 | Above 0.80 to 1.00 |
| G | Above 1.90 | Above 1.00 |
Each label will identify the data center, its operator, facility type, reporting period, location, size category and entry-into-operation date. It will also include renewable-energy information, the PUE and WUE classes and a QR code linking to the public record in the European database.
Which Data Centers Are Covered
The rating system builds on reporting requirements introduced under the EU Energy Efficiency Directive and Delegated Regulation 2024/1364. Operators of data centers with at least 500 kW of installed IT power demand are already within that reporting framework.
Facilities below the 500 kW threshold may participate voluntarily. Data centers still under construction can also submit their expected performance and obtain a label based on the efficiency they are designed to achieve after two years of operation.
The regulation does not impose direct limits on electricity or water consumption. Instead, it establishes a standardized public comparison system intended to make facility performance more transparent and encourage operators to improve efficiency.
Water Stress and Heat Reuse Enter the Assessment
Beyond PUE and WUE, operators will report information concerning local water stress, renewable-energy use, readiness to recover waste heat and the facility’s ability to provide services to the electricity grid.
This gives customers, regulators and infrastructure planners a broader view than PUE alone. A low WUE value, for example, can have different implications depending on the level of water scarcity surrounding the facility.
Assessment: Standardized labels could make efficiency performance a more visible factor in site selection, colocation procurement and infrastructure financing, even though the initial scheme does not establish mandatory minimum ratings.
What Happens Next
EU countries and lawmakers have two months to object to the delegated regulation. If no objection is raised, it will enter into force 20 days after publication in the Official Journal of the European Union.
The European database will automatically generate labels after each reporting period. Labels will normally remain valid from August 15 of their issue year until August 15 of the following year.
The Commission must review the regulation by March 31, 2029, and every three years afterward. That review may consider additional sustainability indicators, third-party auditing, equipment-level efficiency measurements and a combined rating for each facility.
The Commission said the rating system may also support future legislation, including planned minimum performance standards for European data centers.
The complete regulation and annexes are available from the European Commission Directorate-General for Energy.
