To mark the start of the construction phase, leaders from Flow Batteries Europe (FBE) and the FlexBase Group met in Laufenburg, Switzerland to solidify cooperation on addressing energy security at the European level as the growing reliance on renewables continues to drive the need for long-duration storage.

Construction work for the world's largest flow battery started this month at the strategic critical electrical grid interconnection point on the borders of Germany, France, and Switzerland. The site's location will enable the system to stabilise electricity flows across national borders, strengthening Europe's approach to energy resilience and grid stability.

To mark the start of the construction phase, leaders from Flow Batteries Europe (FBE) and the FlexBase Group met in Laufenburg, Switzerland to solidify cooperation on addressing energy security at the European level as the growing reliance on renewables continues to drive the need for long-duration storage.

The flow battery system will be able to store energy for hours or even days, to maintain grid stability during periods of low wind and solar output. The flow battery does not rely on the use critical raw materials, thereby also ensuring energy storage security as well as energy security.

«The collaboration with FBE is an important step for our project and FlexBase as a company», said Marcel Aumer, Group CEO, VRP and Co-founder of FlexBase Group.

«Building a 800MW and 1.6 GWh flow-battery is something, nobody has ever done before. Together as a team and with the knowledge of partners like FBE we're creating a scalable model for managing renewable energy lulls across Europe».

Addressing Europe's critical energy storage gap
FlexBase's Laufenburg facility will feature over 1.6 GWh of storage capacity and an output exceeding 800 MW, covering 20,000 square metres. The installation will showcase one of the safest energy storage technologies available - non-flammable, non-explosive, and free from critical raw materials such as lithium or cobalt.

Flow batteries offer unmatched safety and environmental performance for grid-scale storage. Thanks to its water-based electrolytes and inherently stable chemistry, the system poses no fire risk, allowing data centres, offices, and staff facilities to safely operate within the same building.

Anthony Price, Secretary General of Flow Batteries Europe stressed the need for regulatory frameworks that support long-duration storage technologies such as flow batteries. Studies by the German Institute for Economic Research (DIW) highlight that 351 TWh of long-duration storage may be required to navigate prolonged renewable energy shortfalls—even with cross border grid interconnection.

Flow Batteries Europe is convening a joint working group to develop policy recommendations, which will include experience and information from the Laufenburg project. More about this and the latest trends in the flow battery sector will be discussed at the International Flow Battery Forum, Vienna (24-27 June 2025).