18 June 2025:
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).
Flow batteries leaders meeting in Laufenburg, Switzerland, with participants from the FlexBase Group and Flow Batteries Europe. From left to right: Juergen Wieshoff (FBE), Sascha Berthold (FlexBase), Kees van de Kerk (FBE President), Pascal Wyss (FlexBase), Marcel Aumer (FlexBase) & Anthony Price (FBE Secretary General).
About FlexBase Group – The Power of Innovation for Tomorrow’s World
Founded in 2022 by Marcel Aumer and Sascha Carroccio, FlexBase Group pursues the vision of
creating new and modern workplaces for Laufenburg and the entire region with modern and
innovative technologies in the fields of IT and energy. The group includes FlexBase Holding
GmbH, FB Real Estate AG, FB Data AG, FB Storage AG, FB Power AG and FlexBase Service AG.
The location of the technology center and worlds biggest flow-battery is planned at the “Star of
Laufenburg”, the electricity hub of Central Europe, which offers the best connection to the
electricity grid in Switzerland.
