When the EU set its ambitious goal to draw at least 42.5% of its energy from renewable sources by 2030, it was clear that innovation would play a critical role. Across Europe, private companies and public institutions alike have been pushing boundaries to meet this challenge head-on. Among the most compelling efforts is HEAT-INSYDE, an EU-funded consortium redefining how we store energy.
“This is about more than just reaching a number,” says Henry van der Meer, Product Manager Specialties, who has been involved with the project since its inception in 2020. “It’s about changing how we think about energy in everyday life: how we capture it, store it, and use it when we need it most.”
Born from a collaboration between 11 academic and commercial partners, and initiated by the Eindhoven University of Technology, The Netherlands Organization for Scientific Research, and the Caldic Benelux team, the HEAT-INSYDE project focuses on solving one of renewable energy’s biggest challenges: inconsistency between supply and demand. This requires a storage solution that is sustainable, efficient, and durable.
The team devised a one-of-a-kind heat battery. At its core is a vessel filled with potassium carbonate – a salt that stores thermochemical energy through a hydration and dehydration process. When water is added, the salt hydrates and releases heat; when dehydrated using ambient heat sources, the energy is stored indefinitely in the dry crystals with no leakage or conversion loss.
“We knew we needed a material that was not only effective but scalable. Our technical team worked rigorously to identify potassium carbonate as the ideal thermochemical compound. It delivers on performance and opens the door to a wide range of applications.”
The system draws thermal energy from the environment, be it geothermal, solar thermal sources, or even industrial waste heat to power the dehydration process. It is also compatible with existing heating technologies and can enhance the performance of heat pumps while reducing their energy load.
Real-world trials have been key to refining the technology. The first prototype was tested at a rental residential property in Eindhoven, the Netherlands, using a custom-built shed that harvested ambient heat. From there, systems were rolled out in Cadenet, France, and Gdynia, Poland – locations selected for their differing climates and heating needs. “These distinct environments are essential to fully understand the versatility of our design,” says Henry. “We’ve seen how it responds to real demands - not just lab conditions - and that is an important milestone for any emerging technology.”
We are proud to be part of a transformative journey that besides supporting the energy transition, also demonstrates how innovation and sustainability go hand in hand.
Now entering its final phase, the HEAT-INSYDE project is focusing on broader deployment and affordability. With the potential to reshape both residential and industrial heating, HEAT-INSYDE’s heat battery is positioned beyond a technical achievement; it exemplifies a shared commitment to decarbonization and a belief that chemical ingenuity can power a cleaner future.
In a world accelerating to redefine energy, HEAT-INSYDE’s quiet revolution in heat storage might just be the spark that powers our tomorrow.