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Koolen Industries invests in hydrogen bromine flow battery maker Elestor

Arnhem, The Netherlands. 18 July 2019.


Koolen Industries has signed the agreement for a multi-million investment in the electricity storage company Elestor. After years of research and development, Elestor is at the verge of introducing its revolutionary hydrogen bromine flow battery to the market. This technology is a next step in low cost electricity storage at scale. In addition, EIT InnoEnergy, early day investor of Elestor, co-invested in this round and increased their invested capital considerably.


Elestor's Wiebrand Kout and Guido Dalessi with Kees Koolen
Guido Dalessi (CEO Elestor), Kees Koolen (CEO Koolen Industries), Wiebrand Kout (Founder & CTO Elestor)

The agreement with Koolen Industries forms an important milestone in the development of Elestor, paving the way for a steep growth phase – in virtually every direction – in anticipation of the commercial launch of Elestor’s storage systems.


Kees Koolen, owner of clean energy conglomerate Koolen Industries and former CEO of booking.com and early investor in Uber: “Elestor’s storage systems are designed for large scale stationary applications, whereby the storage costs per kWh are impressively low. With Elestor, another exciting storage technology has been added to the group of companies that we invest in. Since these technologies are complementary and serve a different range of applications, we are together able to deliver turnkey solutions for virtually every demand, in all markets and on a very large scale. The unique Flow Battery technology from Elestor fits extremely well in that strategy.”


The missions of both companies match perfectly: Ensuring that renewable energy is always available for everyone, reliable and safe. Wiebrand Kout (Founder & CTO of Elestor) adds: “Storage against low cost is essential to fulfill this mission and this is where both companies find each other. The Elestor battery is revolutionary because it uses very low cost active materials. Koolen Industries has access to connected technologies. Together, these concepts are key in making renewable energy affordable.”



Guido Dalessi (CEO Elestor) & Kees Koolen (CEO Koolen Industries)


Guido Dalessi, CEO and one of Elestor’s first investors: “While gearing up for series production, we need to increase investments in staff, test facilities, production engineering and automation. The logical subsequent step is to build a giga-factory for large scale production of HBr flow batteries. Teaming up with Koolen Industries is essential to successfully roll out these plans.”


Elestor plans to deliver their first hydrogen container to the municipal yard in Emmeloord, the Netherlands. Also they will deliver two systems to locations in Germany and one to an island off the Norwegian coast.


In 2017, Elestor won the European IDTechEx award for ‘Best Technical Development within Energy Storage’. The jury of this award consisted of Fraunhofer Institut, Berlin University and Toyota Motors Europe.



About Elestor


Elestor BV offers electricity storage systems for industrial use based on the Hydrogen Bromine Flow Battery principle. With a unique and patented design, Elestor matured flow battery technology into a robust and highly scalable product, featuring storage costs per kWh far beyond what is achieved with conventional batteries. Since 2015 Elestor has received multiple seed stage investments from Enfuro Ventures, including strategic support to bring Elestor to its current stage.




About EIT InnoEnergy


EIT InnoEnergy is the innovation engine for sustainable energy across Europe supported by the European Institute of Innovation and Technology. They support and invest in innovation at every stage of the journey – from classroom to end-customer. With their network of partners, they build connections across Europe, bringing together inventors and industry, graduates and employers, researchers and entrepreneurs, businesses and markets.



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