Where battery storage waits for a grid connection
In Germany the grid connection is the bottleneck for battery storage, just as it is for data centres. In 2025 developers applied for grid connections for 573.5 gigawatts of storage. Commitments were given for 54.2 gigawatts. In the distribution grid, which received 98 percent of the applications, only four percent of the capacity applied for won a commitment.
We documented the bottleneck for data centres first. Battery storage shows the same pattern at the same substations. The other hurdles cost a battery project less than a data centre, but they are real. Since January 2026, planning law has privileged battery storage only next to an existing renewable-energy plant or within 200 metres of a substation. The Federal Court of Justice has upheld the Baukostenzuschuss, the up-front contribution a grid operator charges towards the cost of a connection. The grid-fee exemption is to apply only to projects whose final investment decision is taken by the time the new determination is published, planned for 1 January 2027, and which start operating by 4 August 2029. The evidence follows, with the source and evidence grade for every statement.
The Federal Network Agency's figures
In 2025 Germany's distribution and transmission system operators received 18,158 Netzanschlussbegehren, formal requests for a grid connection, for battery storage. That was 194 percent more than in 2024. Together they covered 573.5 gigawatts of power and about 1,583 gigawatt hours of capacity. In the same year the operators issued 1,937 connection commitments, binding offers to sign a grid-connection contract, for a total of 54.2 gigawatts and 142.4 gigawatt hours. Bundesnetzagentur, Aug. 2026
The Federal Network Agency (Bundesnetzagentur) itself points out that applications outnumber real projects. Developers file the same project at several sites. If it wins several commitments, it is usually built at only one of them. The survey does not yet distinguish between stand-alone storage on the grid and storage co-located with a generating plant. Bundesnetzagentur, Aug. 2026
| Grid level | Applications 2025 | Capacity applied for | Commitments on 2025 applications | Capacity committed | Share committed |
|---|---|---|---|---|---|
| Distribution grid | 17,775 | 406.8 GW | 1,429 | 16.8 GW | 4 % |
| Transmission grid | 383 | 166.7 GW | 39 | 17.2 GW | 10 % |
| Total | 18,158 | 573.5 GW | 1,468 | 33.9 GW | 6 % |
Project sizes vary widely. In the transmission grid, the average committed project has 384 megawatts of power and 841 megawatt hours of capacity; in the distribution grid, 14 megawatts and 44 megawatt hours. For comparison, the Marktstammdatenregister, the national register of energy installations, lists 1,292 battery storage systems connected at medium voltage or above. Together they have about 3.6 gigawatts and 6 gigawatt hours. By 1 April 2026 the transmission system operators had already issued 64 commitments for 24.7 gigawatts, including further applications from the previous year. That is almost as much as in the whole of 2025, when there were 71 commitments for 27.3 gigawatts. Bundesnetzagentur, Aug. 2026
In the transmission grid, battery storage makes up most of the queue that led to the maturity procedure. At the end of the third quarter of 2025, 717 applications for about 270 gigawatts were pending there. Of these, 545 applications for 211 gigawatts were for battery storage. Transmission system operators' press release, Feb. 2026
The commitment rate is the telling figure. If the distribution grid commits only four percent of the capacity applied for, its connection is the bottleneck for the typical project of 10 to 50 megawatts. A data centre of that size is also connected to the 110 kV grid, by the same grid operator and at the same substation. Our inference
Grid operators may refuse, and may choose the procedure
On 30 March 2026 the Federal Network Agency dismissed a storage investor's abuse complaint against E.DIS Netz. The grid operator had refused to connect a large stand-alone battery, even at reduced capacity. It had pointed to the risk of supply shortfalls in its network area. That was enough for the agency's ruling chamber. E.DIS did not have to offer a flexible connection agreement (§ 17(2b) EnWG), because the law permits such agreements but does not require them. In the agency's view, the Power Plant Grid Connection Ordinance (KraftNAV) never applied to large battery storage, not even before its amendment of 23 December 2025. Trade press on BK6-25-325; we have not seen the decision text
On 4 May 2026 the same ruling chamber set out the framework. A refusal need only be reasoned well enough to be understood, and the grid operator does not have to disclose network data. Temporary obstacles count as impossibility. The reason is that the Energy Industry Act (EnWG), unlike the Renewable Energy Sources Act (EEG), gives no right to grid expansion for an individual project. The right is to a connection to the grid as it stands (wie es steht und liegt). As § 17 EnWG prescribes no particular procedure, an operator may also replace first come, first served (the Windhundprinzip) with a maturity procedure for capacity not yet firmly allocated. Law-firm report on BK6-25-287; we have not seen the decision text
Anyone who wants to connect a battery can therefore rely neither on a place in the queue nor on a particular procedure. Priority is earned the same way as for a data centre: with secured land, progress on consent, firm orders for transformers and switchgear, and a relationship with the grid operator. Our inference
Privileged, but only within 200 metres
Since 1 January 2026, § 35(1) of the Federal Building Code (BauGB) has privileged two kinds of battery storage in the Außenbereich, the undeveloped land outside built-up areas. A privileged project may be built there without a local development plan. Number 11 covers storage with a spatial and functional link to an existing renewable-energy plant. Number 12 covers any other storage that meets three conditions. It lies no more than 200 metres from the boundary of a substation site or of a power plant of 50 megawatts or more. The substation steps down from extra-high to high voltage, or from high to medium voltage. It has a rated power of at least 4 megawatts. And the total area of all storage approved this way in the municipality exceeds neither 0.5 percent of the municipal area nor 50,000 square metres. The owner must also commit to dismantling the plant. Statute text
The background: on 13 November 2025 the Bundestag first passed an almost unrestricted privilege for storage from 1 megawatt hour. On 4 December 2025, before it took effect, the Bundestag replaced it with the two provisions above. A purely market-driven battery outside the 200-metre radius is not privileged and needs a local development plan (Bebauungsplan). Falling back on Number 3 (public-utility installations) is now seen as barely possible for such plants. Since 2025 Bavaria has exempted grid-serving storage under Number 3 from the permit procedure. Such a project then has no final, unappealable permit, however. Law-firm report, Dec. 2025
Within the 200-metre radius, planning law reflects the same scarcity. The legislator favours exactly the plots next to the substation, which is also where the physical route to a grid connection is shortest. A site that meets Number 12 clears the consent hurdle by statute and needs no council resolution. No decision yet records how authorities read the "spatial and functional link" or the area cap per municipality. Our inference
What the hurdles cost, and from when
Baukostenzuschuss (connection cost contribution)
On 15 July 2025 the Federal Court of Justice ruled (EnVR 1/24) on a purely grid-connected storage plant. The Federal Network Agency need not stop a distribution system operator from charging it a Baukostenzuschuss under the power-price model. The charge is based on the withdrawal capacity applied for. As with a generator, no contribution is due for feeding power into the grid. The court noted that storage is already exempt from grid fees and enjoys tax advantages. A further exemption would shift connection costs onto all grid users, while the revenue from price spreads stayed with the storage operator. Court press release
Grid fees
In the interim report on its grid-fee reform, published on 27 May 2026, the Federal Network Agency keeps the exemption under § 118(6) EnWG for projects already under way. New battery storage will pay a moderate capacity charge equal to the generators' feed-in charge, but no energy charge. The capacity charge is expected to start at €4 to €7 per kilowatt per year. For existing storage, the charge starts only when the special rule expires. Dynamic grid fees for storage are to come in 2030 at the earliest, and by 2033 if possible. Agency press release
The cut-off date is set by the final draft determination (Festlegungsentwurf). Consultation on it closed on 18 September 2026, and the determination is due to be published on 1 January 2027. The 20-year exemption remains for projects whose final investment decision is taken by publication and which start operating by 4 August 2029. The decision counts as taken once binding orders for components cover at least half of the investment volume and cannot be cancelled without substantial financial loss. This must be proved to the grid operator by 31 March 2027. Trade press on the draft; we have not seen the draft text
Transformers and switchgear
Large power transformers take about 128 weeks to deliver on average, medium-voltage switchgear 26 to 32 weeks and gas-insulated switchgear about 18 months. Battery storage and data centres order from the same manufacturers. Wood Mackenzie 2026, specialist suppliers The evidence is on the page "Where the bottleneck is".
For battery storage, the cost hurdle hangs on a cut-off date that data centres do not face. A project that has not firmly ordered components covering at least half of its investment volume by the time the determination is published, planned for 1 January 2027, loses the 20-year exemption and will pay the capacity charge. In the maturity procedure, the same order also earns points under the sub-criterion "orders". One order therefore pays off at two hurdles. Our inference
What the data do not show
The Federal Network Agency does not yet separate stand-alone from co-located storage in its application data, but has said it will. Commitment rates by control area or by grid operator are not published. The four percent is a national average across all distribution system operators. Bundesnetzagentur, Aug. 2026
As with data centres, what decides a site is how much headroom the responsible grid operator has at that substation. Nobody publishes that figure. The 200-metre radius of Number 12 at least shows a developer where to ask. Our inference
Transmission or distribution grid? → The maturity procedure →
Where the statements come from
- Applications, commitments, power and capacity for 2025 and up to 1 April 2026, installed base in the Marktstammdatenregister, average sizes, multiple filings: Bundesnetzagentur, "Stand der Batteriespeicheranfragen 2025/2026" (status of battery storage requests), published on SMARD on 20 August 2026. Primary source. Checked against pv magazine of 25 August 2026; no discrepancies.
- 717 applications, about 270 gigawatts, of which 545 applications and 211 gigawatts were battery storage, as at the end of the third quarter of 2025: 50Hertz, Amprion, TenneT and TransnetBW, press release of 5 February 2026. Primary source.
- Storage connection refused by E.DIS Netz, KraftNAV, flexible connection agreement: Bundesnetzagentur, decision BK6-25-325 of 30 March 2026, reported by pv magazine on 22 May 2026. We have not seen the decision text itself; the source is the trade press.
- Depth of reasoning, impossibility, "as it stands", change of procedure: Bundesnetzagentur, decision BK6-25-287 of 4 May 2026, reported by Rödl & Partner on 24 June 2026. We have not seen the decision text itself; the source is a law-firm report.
- § 35(1) Numbers 11 and 12 and § 35(5) BauGB: statute text, gesetze-im-internet.de, as at 15 September 2026. Primary source.
- Legislative process of 13 November and 4 December 2025, Number 3, Bavaria: CMS Hasche Sigle, Legal Update of 8 December 2025. Law-firm report.
- Baukostenzuschuss: Federal Court of Justice, press release No. 129/2025 on decision EnVR 1/24 of 15 July 2025. Primary source.
- Grid fees, capacity charge, dynamic fees: Bundesnetzagentur, press release of 27 May 2026. Primary source. Cut-off date, definition of the investment decision, proof by 31 March 2027: pv magazine of 6 August 2026 on the draft determination. We have not seen the draft itself (bundesnetzagentur.de/1059162); the source is the trade press.
- Lead times: as evidenced on the page "Where the bottleneck is".
- Not on this page: what we conclude from these findings for our own projects, and whether a battery storage plant can be financed under the capacity charge after 2029. We publish what we have evidenced.