- Home
- News & insights
- Insights
- Battery storage syst…
2025年12月19日
Publication series – 6 / 78 观点
Battery storage systems in outdoor areas - current classification in accordance with § 35 BauGB
- Briefing
The permissibility of battery storage systems (BESS) in greenfield areas has been characterized by considerable uncertainty for a long time. BESS were not expressly regulated in the German Building Code (BauGB) and their classification as privileged projects was handled inconsistently in administrative practice. In some cases, a privileged status as power supply facility pursuant to Sec. 35 para. 1 No. 3 BauGB was granted and in some cases explicitly denied.
With the most recent amendments to Sec. 35 para. 1 No. 3 BauGB, the legislator has introduced independent privileges for NESS for the first time. The new regulation is the result of a short-term and quite turbulent legislative process.
Legislative starting point and structure of the new regulation
The starting point for the reform was the recognition that battery storage systems play a central role in a flexibilized energy system, without their classification under planning law having been clearly defined to date. In the meantime the German Bundestag had even decided on November 13, 2025 to grant largely unrestricted privileges to stand-alone projects. However, after strong headwinds, particularly from the federal states and local authorities, another Bundestag resolution immediately followed on December 4, 2025, which now differentiates the legal situation. It is expected that both resolutions will come into force on January 1, 2026, meaning that the unrestricted regulation will most probably not apply (not even for a short time) and will instead be immediately overlaid by the restricted version.
The version of Sec. 35 para. 1 No. 3 BauGB then in force distinguishes between two independent facts for BESS in greenfield areas, each of which is linked to different functional and spatial requirements. Sec. 35 BauGB then does, however, not contain any general privileges anymore.
BESS in a spatial-functional context with renewable energy generation systems
According to the new Sec. 35 para. 1 No. 11 BauGB, BESS that are spatially and functionally connected to an existing renewable energy plant are considered privileged. In particular, this includes storage systems that are assigned to a wind energy system or a ground-mounted photovoltaic system and are intended to at least partially absorb its electricity.
The legislator uses the concept of spatial-functional connection known from public planning law. A technically and economically viable connection is required, although the explanatory memorandum to the law leaves the details open. However, a subordinate or serving function of the storage, as previously required for so-called ‘mitgezogene Privilegierung’, is not required.
It is also of practical importance that the privileged storage system does not necessarily have to have been approved on the same planning law basis as the BESS. Battery storage systems that are connected to systems that were themselves built on the basis of a development plan may also be eligible for the privileged status. This significantly expands the scope of application compared to previous constructions of the ‘mitgezogene Privilegierung’.
However, ambiguities remain with regard to the definition of the spatial reference and the question of what stage the production plant must be at in order to be considered ‘existing’. The better arguments might possibly speak for basing this on the time of approval of the production plant in order to avoid accidental results for example due to construction delays.
Independent BESS in the proximity of energy infrastructure
In addition, Sec. 35 para. 1 No. 12 BauGB (new version) grants a privilege for stand-alone battery storage systems without direct allocation to a renewable energy plant. However, this option is linked to several cumulative requirements.
Firstly, a minimum capacity of the storage system of 4 MW which, however, will be achieved by the vast majority of stand-alone projects without any problems. It is also necessary that the storage location must be no more than 200 meters from the boundary
- of a substation at the extra-high to high voltage or high to medium voltage level or
- an operating or decommissioned power plant with a rated electrical output of at least 50 MW.
It is noteworthy that the law does not expressly require the substation to be in operation or approved nor does it require them to be substations of the grid operator. This means that substations planned together with the BESS may also fulfill the proximity requirement, which would significantly expand the scope of application of this option. It also remains unclear how the distance of 200 meters is to be determined. The genesis of the standard and legislative materials speak in favour of a 200-metre distance from property boundary to property boundary; however, a 200-metre corridor is also being discussed, as known, for example, from the privileged approval of ground-mounted PV systems in accordance with Sec. 35 para. 1 No. 8 BauGB.
In addition the privilege pursuant to Sec. 35 para. 1 No. 12 BauGB (new version) is subject to an area-related upper limit at municipal level. The total area occupied by privileged battery storage facilities, including ancillary facilities, may not exceed 0.5% of the municipal area per municipality and may not exceed 50,000 m². The limit that is reached first is decisive. This limit means that the realization of larger battery parks in greenfield areas is in fact severely restricted and a "greyhound race" for the reservation of areas per municipality is likely to arise. It should also be noted that the usual calculation of floor space in accordance with the BauNVO is not be applied, but that open spaces and access routes, for example, must also be taken into account.
Legislative objectives and control approach
The new regulation clarifies that although the legislator recognizes battery storage systems as system-relevant/ critical infrastructure, he wants to deliberately steer their realization in greenfield areas. Storage facilities that are either integrated into existing generation structures or are linked to existing energy industry locations are given priority.
At the same time, performance, distance and area criteria are intended to prevent uncontrolled use of outdoor areas and the widespread establishment of large storage parks. The privileged status thus becomes an instrument of spatial control, not a blanket facilitation. In particular for large BESS projects that cannot be accommodated within an area of 5 ha, the possibilities offered by zoning plan (Bauleitplanung) and planning approval decisions (Planfeststellungen) are likely to become increasingly attractive in the future.
Classification compared to the legal situation before the reform
Prior to the introduction of the new legal provisions, battery storage facilities in greenfield areas were not expressly privileged. In some cases, approval practice resorted to Sec. 35 para. 1 No. 3 BauGB and classified storage facilities as installations for the public power supply. This regularly required a particular location and led to widely divergent results across Germany. In several federal states, there were also administrative statements that fundamentally rejected the privileged treatment of battery storage systems.
Against this backdrop, the new regulation creates an independent assessment standard under federal law for the first time, even if this is associated with restrictions in the most recently adopted version.
Practical significance and remaining questions of interpretation
The new privileges lead to a clearer system but leave numerous questions of interpretation unanswered. This concerns in particular:
- the determination of the spatial-functional connection,
- permissible performance values and operating concepts for co-located projects,
- the specific measurement of the 200-meter distance and
- the calculation and updating of municipal area quotas.
In a motion for a resolution adopted on December 19, 2025, the Federal Council (Bundestag) draws attention to the numerous questions of interpretation and suggests that the standard be tightened up again. Further amendments may therefore be expected in the new year.
Regardless of admissibility under construction planning law, battery storage facilities remain subject to other public law requirements, in particular nature conservation and species protection law, water- and fire protection law and must also continue to overcome the "bottleneck" of grid connection. The administrative practice will have to show to what extent the new regulation actually contributes to more planning security and an acceleration of storage projects.
本系列内容
Will the new German government open the door for carbon capture and storage?
2025年2月26日
作者 作者
The new CO2 border adjustment mechanism (Carbon Border Adjustment Mechanism - “CBAM”) - first statutory reporting obligations set for January 2024
Power Play: Renewable Energy Update
2023年11月3日
New IT security requirements for the energy sector
Power Play: Renewable Energy Update
2023年9月1日
作者 Dr. Paul Voigt, Lic. en Derecho, CIPP/E, Alexander Schmalenberger, LL.B.
Does monument protection hinder the expansion of renewable energies?
Power Play: Renewable Energy Update
2023年8月16日
The amending law to strengthen digitisation in the urban land use planning process and the further expansion of renewable energies
Power Play: Renewable Energy Update
2023年7月6日
Challenges for data center operators - The federal government’s draft bill for an energy efficiency act
Power Play: Renewable Energy Update
2023年4月12日
作者 作者
Ordinance for Determining Critical Infrastructures (KritisV): Renewable energy plants as critical infrastructure and requirements for IT protection
Power Play: Renewable Energy Update
2022年7月12日
作者 Dr. Paul Voigt, Lic. en Derecho, CIPP/E, Dr. Markus Böhme, LL.M. (Nottingham)
Liquefied Natural Gas Projects in Germany: The LNG Acceleration Act
Q&A series: Energy & Infrastructure
2022年6月10日
Participation of local municipalities in the context of wind and photovoltaic projects
Power Play: Renewable Energy Update
2022年5月5日
Building energy performance: the revised Energy Performance of Buildings Directive
Power Play: Renewable Energy Update
2022年2月14日
Fit for 55 – Hydrogen and the Reform of the European Gas Market
Power Play: Renewable Energy Update
2022年1月11日
Renewable Energy Wrap-Up – Poland
Power Play: Renewable Energy Update
2021年9月21日
作者 Olav Nemling
Floating Foundations for Offshore Wind Farms
Power Play: Renewable Energy Update
2021年6月8日
Species protection exemption: Significance for wind energy
Power Play: Renewable Energy Update
2021年5月25日
Related Insights
EEG 2027 – Overview of the Planned Amendment to the Renewable Energy Sources Act
作者 Dr. Markus Böhme, LL.M. (Nottingham) 以及 Dr. Christian Ertel
Amendment to the Energy Industry Act: changes for energy supply companies and grid and system operators
作者 Dr. Christian Ertel 以及 Dr. Markus Böhme, LL.M. (Nottingham)
Challenges for data center operators - The federal government’s draft bill for an energy efficiency act
Power Play: Renewable Energy Update
作者