Electricity distribution grid operators may charge construction cost subsidies for grid connections of battery storage systems. This was decided by the Federal Court of Justice (BGH) on July 15, 2025 (Az EnVR 1/24). The amount of the construction cost subsidies may be calculated according to the performance price model established by the Federal Network Agency. This can have a far-reaching impact on the financing and expansion of this technology. In the world of renewable energies and in the context of the energy transition, this represents a minor setback, as the previous decision by the lower court had raised hopes that construction cost subsidies for battery storage systems would be abolished. However, this decision has now been rejected by the BGH. We explain the background:
Building cost subsidies have a steering and control function
Grid operators can demand the payment of a one-off construction cost subsidy from the subscriber for the permanent provision of connected load. In its ruling, the BGH confirmed that grid operators may charge construction cost subsidies – including for battery storage – on the basis of the position paper of the Federal Network Agency in the area of grid levels above low voltage 2009 (BK6p-06-003). The construction cost subsidy is thus intended to have a steering and control function. The higher the power requirement, the more expensive the connection will be. This is intended to encourage subscribers to apply for the grid connection according to their actual power requirements. The amount of the construction cost subsidy can vary from region to region. This has also been recognized by the BGH, which describes it as “location-controlling”.
Charging building cost subsidies does not violate the ban on discrimination
The core issue of the decision is the question of whether the grid operator has violated the prohibition of discrimination. The levying of construction cost subsidies above low voltage is not enshrined in law, but is derived from Section 17 EnWG. According to this, grid operators are obliged, among other things, to provide a non-discriminatory connection to their grid. Unlike end consumers, battery storage systems do not consume the electricity drawn from the grid (apart from storage losses). Instead, they feed the electricity back into the grid at a later point in time. The BGH recognized this difference, but denied the existence of discrimination in comparison to end consumers. The lower court (OLG Düsseldorf, decision of 20 December 2023 – VI-3 Kart 183/23) took a different view and declared the unchanged calculation of the construction cost subsidy for battery storage systems according to the demand price model to be discriminatory. Following the BGH ruling, it is now clear that battery storage systems may continue to be treated like traditional end consumers with regard to the charging of construction cost subsidies.
Battery storage systems are already sufficiently privileged
The BGH’s argument is also based on the fact that the legislator “privileges and promotes” battery storage systems in many ways, both by exempting them from grid fees and through taxation. Connection costs should not be passed on to the grid fees and ultimately have to be shouldered by the end consumer. However, it should be noted that the exemption from grid fees pursuant to Section 118 (6) sentences 1 and 3 EnWG is only limited until 2029 and an extension of the exemption is currently unclear. In addition, Section 118 (6) sentence 1 EnWG and Section 5 (4) StromStG alone are intended to avoid a double burden on battery storage systems.
Despite these privileges, many battery storage projects are still in the planning phase. According to the battery charts from RWTH Aachen University, only 340.4 MWh of large storage systems (>1 MWh) are currently in planning, with a predicted increase to 7,200 MWh by the end of 2027. This clearly shows that the “legislative privilege” on which the BGH is based is not a genuine subsidy.
Outlook
Operators of battery storage projects now need to factor the construction cost subsidy into their planning. As this can represent an enormous financial hurdle, the search for a location will be particularly crucial. The decision also raises the question of whether large-scale battery storage systems of more than 100 MW are also affected, as they were not the subject of the proceedings. It remains to be seen how grid operators and the Federal Network Agency will react to the decision.
