Battery Storage Additions in Germany on Record Pace in First Half of 2026

Münster — The expansion of battery storage in Germany continues to accelerate. In the first half of 2026, new installations reached a record level, according to a new IWR analysis of the Bundesnetzagentur's Marktstammdatenregister. At the same time, the storage market is developing faster than the German federal government's current energy policy accounts for.

Both newly installed capacity and storage volume rose sharply, with significant differences between federal states. While investors are increasingly turning to larger battery storage systems, hybrid projects and longer storage durations, this segment has so far played only a minor role in energy policy discussions on securing dispatchable capacity. New gas-fired power plants remain the primary focus as replacements for retiring coal-fired plants.

Bavaria and Saxony-Anhalt Lead Growth Among Federal States

From January to June 2026, nationwide installed capacity rose to 2,482.7 MW, an increase of around one-third compared with the same period last year (1,872.5 MW). Newly installed storage volume grew by nearly 76 percent to around 5,642 MWh (previous-year period: 3,206.4 MWh). The number of newly installed systems rose from 279,582 to 286,060. Germany now has around 2.6 million battery storage systems connected to the grid, with a combined capacity of 18,483.5 MW and 31,485.1 MWh. If the growth trend continues, installed capacity could reach around 35,000 MWh (35 GWh) by the end of 2026, according to IWR estimates.

Among the federal states, Bavaria led in newly installed capacity with 520.3 MW (previous year: 382.4 MW), ahead of North Rhine-Westphalia with 419.9 MW (385.1 MW) and Lower Saxony with 386.6 MW, more than double the previous-year figure of 189.1 MW. In terms of storage volume, North Rhine-Westphalia led with 1,179.3 MWh, ahead of Bavaria (1,061.3 MWh) and Lower Saxony (848.3 MWh).

Saxony-Anhalt stood out in particular: newly installed capacity there rose from 34.6 MW in the previous-year period to 277.8 MW, while storage volume increased from 63.6 MWh to 632.6 MWh. Further growth is expected in the coming quarters, with two of Germany's largest utility-scale battery storage projects currently under development in the state — a 716 MWh storage system in Förderstedt (Eco Stor) and a 1,000 MW storage system with up to 5,700 MWh in Klostermansfeld (BW ESS), construction of which began in early July 2026. By contrast, additions declined in Schleswig-Holstein, Brandenburg and Thuringia.

Hybrid Projects and Grid-Supportive Storage Gaining Importance

Alongside the expansion of standalone large-scale storage, the number of projects combining wind and solar farms directly with battery storage is increasing. Such hybrid systems allow generation peaks to be temporarily stored, grid connections to be used more efficiently, and electricity to be fed in during periods of high demand. At the same time, grid-supportive battery storage systems are increasingly being developed to ease grid congestion, reduce redispatch measures and provide additional flexibility for the power system. This development is accompanied by a trend toward longer storage durations, with battery storage increasingly taking on load-shifting and renewable energy integration functions.

Trend Toward Longer Storage Duration Continues

The average storage duration of newly installed systems rose from 1.7 to 2.3 hours compared with the same period last year. In addition to short-term system services, arbitrage trading, load shifting and the integration of variable wind and solar generation are becoming increasingly important. This trend is reflected in projects by Swedish company Flower Infrastructure Technologies: a 100 MW storage system with 400 MWh capacity in Hamburg-Bergedorf has been construction-ready since May 2026, though commissioning is not planned until late 2028. Flower has also taken over a further four-hour project with 63 MW and 257 MWh in Döllnitz, Saxony-Anhalt. The main drivers are falling system and battery costs, which make longer storage durations more economically attractive than just a few years ago.

Policy Lags Behind Market Pace: StromVKG and Grid Fee Reform Weigh on Storage

Two current policy developments illustrate how far energy policy is lagging behind market growth: the StromVKG and the reform of the grid fee system (AgNes). Under the StromVKG, passed by the Bundestag and Bundesrat on July 9-10, 2026, the federal government is introducing a central capacity market. Starting in September 2026, 9 gigawatts of long-term capacity will initially be tendered to bridge multi-day periods of low wind and solar output ("Dunkelflaute"), benefiting primarily new gas-fired power plants; separate tender rounds for battery storage will not follow until 2027 and 2029. BDEW and VKU broadly welcome the capacity market, while BNE opposes it. Storage association BVES considers the exclusion of batteries to be in breach of EU law and filed a complaint with the EU in June 2026 as a result.

The reform of the grid fee system (AgNes) has proceeded similarly slowly. The existing 20-year grid fee exemption for storage under Section 118(6) of the German Energy Industry Act (EnWG) was under review in early 2026, before the Bundesnetzagentur issued a preliminary interim ruling on May 27, 2026, granting grandfathering protection — valid only if the investment decision is made before the new AgNes ruling takes effect and the system enters operation by August 4, 2029. The final ruling itself is expected to be adopted after a formal consultation in late 2026.

Source: IWR Online, 20 Jul 2026