# Eos Energy zinc-bromide battery storage, 7.5 MW and 30 MWh, planned in Gaggenau, Germany for 2028

- Published: 2026-11-14 00:44 UTC
- Section: Power & Energy › Batteries
- Tags: zinc-bromide battery, grid energy storage, Eos Indensity, 7.5 MW storage, 30 MWh storage, Stadtwerke Gaggenau, CAPAC AG, lithium-free battery, non-flammable electrolyte
- URL: https://realtech.media/news/rt-73cd3feb4c637fc1249f9d18_eos_energy_zinc/

**Stadtwerke Gaggenau and CAPAC AG plan a 7.5 MW, 30 MWh storage plant on a former gas storage site; construction is set for 2027, launch for 2028.**

![Eos Energy zinc-bromide battery storage, 7.5 MW and 30 MWh, planned in Gaggenau, Germany for 2028](https://realtech.media/media/2026/11/1f00a2dac85dcbb2.jpg)
*Kecko from Eastern Switzerland, Wikimedia Commons, CC BY 2.0*

A large energy storage system based on zinc-bromide batteries is planned in Germany, according to ixbt.com. It is to deliver up to 7.5 MW and store up to 30 MWh of energy [1]. The project is run by the utility Stadtwerke Gaggenau and the energy company CAPAC AG, with technology supplied by the US company Eos Energy Enterprises [1]. Construction is planned to begin in 2027, with launch scheduled for 2028 [1].

## Chemistry and design

The Eos Indensity system uses aqueous zinc-bromide chemistry, without lithium, cobalt, vanadium or rare earth elements [1]. The electrolyte is non-flammable, which lowers the risk of fire and explosion, so battery modules can be placed more densely [1]. The design resembles Lego: blocks can be stacked or placed side by side to save area. The system needs no active cooling and is rated for temperatures from -20 to 50 °C. The developers promise a service life of up to 25 years, with capacity loss over that period not exceeding 3.6%, by their estimate [1].

## Operation and site

The plant will run in a four-hour mode: it will store surplus electricity during high output of solar and wind plants and feed it into the grid when demand rises [1]. The technology itself supports storage durations of 4 to 16 hours. The project cost is estimated at about 15.2 million euros [1]. It will be built on the grounds of a former liquefied gas storage facility of Stadtwerke Gaggenau. After launch, the site is expected to become one of the largest zinc-bromide energy storage complexes in Europe [1].

## Sources

1. [ixbt.com](https://www.ixbt.com/news/2026/11/14/v-germanii-postroiat-pauerbank-na-30-mvtc-bez-litiia-i-kobalta-on-rasscitan-na-25-let-raboty-i-temperatury-do-20-c.html)
2. [Interesting Engineering](https://interestingengineering.com/energy/germany-30mwh-zinc-bromine-battery-storage)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-73cd3feb4c637fc1249f9d18_eos_energy_zinc/