The Energy Efficiency Act (EnEfG) came into force on 18 November 2023 and serves as a national implementation act for the amended EU Energy Efficiency Directive (EED) to achieve European energy and climate protection targets.
According to the Federal Ministry for Economic Affairs and Climate Protection (BMWK), there are more than 3,000 data centres in Germany. In view of the enormous demand for electricity - across the EU, data centres consume around 3-4% of the total electricity demand, and the trend is rising - the EED and EnEfG are establishing new requirements for data centres in particular with regard to energy efficiency and the reusability of energy. The obligations arising from the EnEfG relate to data centres with a non-redundant nominal connected load of 300 kW or more. According to the BMWK, this includes around 1,000 data centres in Germany.
With regard to waste heat data, a reporting obligation for affected companies and thus also for data centres has been in force since 1 January 2025 (the original reporting deadline of 1 January 2024 has been suspended). The corresponding data must then be submitted annually by 31 March in accordance with Section 17 (2) EnEfG.
Obligation to report waste heat data
The Federal Centre for Energy Efficiency (BfEE) has set up a waste heat platform to monitor the waste heat generated and potential waste heat capacities. The platform is intended to improve the centralised collection of data on waste heat utilisation in the future. It is also intended to create better transparency about waste heat potential on the market. Accordingly, waste heat utilisation is a key component of the energy transition.
These new reporting obligations also affect data centre operators, who must report the following data for the previous calendar year by 31 March of each year, Section 17 (1, 2) EnEfG:
- Name of the company
- Address of the site or sites where the waste heat is generated
- The annual heat quantity and maximum thermal output
- Availability over time in the form of performance profiles throughout the course of the year
- The existing options for controlling temperature, pressure and feed
- The average temperature level in degrees Celsius
The initial deadline for submitting the relevant information was 1 January 2025. On 15 January 2025, the BfEE published data from the waste heat platform for the first time. These include over 2,600 companies and their more than 19,000 waste heat potentials with an annual waste heat volume totalling 160 TWh.
In addition, Section 17 (1) EnEfG generally stipulates that companies are obliged to provide data on waste heat generated at the request of operators of heating networks or district heating supply companies and other potential heat-consuming companies.
Companies that violate the new reporting obligations or fail to fulfil them on time face fines of up to 100,000 Euros.
What other obligations does the EnEfG provide for data centres?
Section 4 of the EnEfG concerns energy efficiency in data centres. The energy efficiency requirements differentiate between requirements for energy consumption effectiveness and for the proportion of reused energy.
Data centres that go or went into operation before 01.07.2026 must comply with energy efficiency values of a maximum of 1.5 from mid-2027 and 1.3 by mid-2030. In addition, the general efficiency requirements for companies must be considered (Sections 16 et seq. EnEfG), according to which the waste heat generated must be avoided using state-of-the-art technology and the waste heat generated must be reduced to the proportion of technically unavoidable waste heat, insofar as this is possible and reasonable.
Stricter requirements (still) apply to data centres that commence operations after 01.07.2026. These must achieve an energy consumption efficiency value of a maximum of 1.2 and fulfil the further requirements of Section 11 (2) EnEfG on waste heat utilisation. These requirements must be met on a permanent basis no later than two years after commissioning on an annual average. With regard to waste heat utilisation, such data centres must achieve a share of at least 10% to a maximum of 20% reused energy, depending on the commissioning date.
However, there is often a lack of the required customers for the heat or heating infrastructure, which is why the exemptions in Section 11 (3) EnEfG are already coming into focus.
- If the proportion of reused energy no longer meets the requirements after commissioning due to subsequent events and through no fault of the data centre operator.
- If there is an agreement on waste heat utilisation between the data centre operator and a neighbouring municipality or the operator of a heating network with a concrete intention to meet the requirements for waste heat utilisation within 10 years.
- If the operator of a heat network in the vicinity does not accept an offer to use reused energy at cost price within six months, even though the operator of the data centre has the necessary infrastructure in place to provide the heat, in particular in the form of a heat transfer station.
Section 11 (3) sentence 2 EnEfG sets out an obligation for heating network operators, according to which they must provide information on the capacity of the heating network when submitting an offer for waste heat utilisation by a data centre operator.
