Over 150 participants from 29 countries joined either in person or online to exchange knowledge and strengthen collaboration on accelerating the deployment of thermal energy storage technologies.
The TES workshop aims to advance the development and implementation of thermal energy storage solutions by bringing together researchers, industry representatives and policymakers for two days of expert presentations, panel discussions and networking opportunities. It is organised by the Gemini Centre for Thermal Energy Storage, which is a joint initiative between SINTEF Energy Research and the Norwegian University of Science and Technology (NTNU)’s Department of Materials Science and Engineering.
The 2025 edition featured nine expert presentations from both research and industry representatives, as well as two panel discussions.
Thermal energy storage: a key contributor to decarbonisation, efficiency and resilience
Thermal energy storage has a vital role to play in our future energy systems. Not only can it facilitate the decarbonisation of industry by providing the flexibility needed to integrate renewable energy sources and replace fossil fuels with electrification, but it can also save money and resources by improving energy efficiency.
In recent years, thermal energy storage has taken on additional significance as a means of strengthening energy security, and ensuring continued operations regardless of external circumstances.
Leader of the Gemini Centre Jorge Salgado Beceiro (SINTEF Energy Research) used this perspective to set the scene in his introduction to the workshop. He referred to the Iberian Peninsula Blackout that took place in April 2025, when vast areas of Spain and Portugal experienced a power blackout for over ten hours. The cause was later determined to be grid fragility.
Jorge noted the challenges of rapid electrification in the context of increasingly intermittent, price-varying energy production and a growing demand. He emphasised the importance of thermal energy storage in helping “bridge the gap between production and demand”. As of October 2025, Spain has allocated a total of EUR 840 million in funding to establish a combined 2.4 GW of new energy storage capacity.
Day one: Flexibility for industrial heating
The first day focused on flexibility for industrial heating, and was sponsored by the HiTES project, led by SINTEF Energy Research and co-funded by the Norwegian Research Council. HiTES seeks to develop high-temperature thermal energy storage solutions for the process industry. These solutions are needed to enable the flexibility required for industrial electrification. Both research and industry project partners participated in the presentations and panel discussion.
Galina Simonsen (SINTEF Energy Research) opened the session by presenting how industry and research can advance the integration of thermal energy storage by collaborating in European projects.
Til Holmes (SINTEF Energy Research) followed with results from system modelling studies, highlighting how thermal energy storage integration can provide flexibility benefits for both energy use and cost efficiency.
Anton Beck (Austrian Institute of Technology) then presented a cost-efficiency tool being optimised within HiTES to support the selection and integration of thermal energy storage in industrial processes.
The day concluded with a panel discussion featuring Hanne Kauko (SINTEF Energy Research), Alexis Sevault (Cartesian) and Sturla Sæther (Equinor), moderated by Jorge Salgado Beceiro. The panel identified key gaps that must be addressed to enable the wider integration of TES in industrial processes. Discussion topics included whether seasonal storage should be prioritised, or whether flexibility would be better achieved through hybrid systems combining multiple storage technologies.
Day two: Research needs within thermal energy storage
The second day focused on research projects and technical progress within thermal energy storage.
Ge Song (NTNU EPT) opened the day with her work on model predictive control integrating thermal energy storage with reinforced learning.
Halvard Thon (SINTEF Industry) then presented his work on direct-contact thermal energy storage with phase change materials (PCM). The results showcase the high energy density, rapid charge and discharge rates, and high round-trip efficiency of direct-contact systems.
Gerald Englmair (Technical University of Denmark) presented his work on PCM for cooling, carried out in the La-Flex project, also led by SINTEF Energy Research. He also introduced the International Energy Agency (IEA)’s Task 47 on components for thermal energy storage.
Petri Trygg (Polar Night Energy) showcased the company’s thermal energy storage, which uses sand as a storage medium. This presentation attracted particular interest through examples of operational units already installed in Finland.
Silvia Trevisan (KTH) followed with another technology showcase, presenting results from real-world operation of thermal energy storage units supplied by Kyoto Group.
Wim Van Welden (AEE Intec) closed the presentations, with an introduction to his work on large-scale TES integration. He introduced the TREASURE project, and his coordination work in the IEA Task 45 on large TES.
The workshop was closed by a second panel discussion, featuring Wim, Silvia, Gerald and Fride Vullum-Bruer (SINTEF Energy Research), on ways to accelerate visibility and research support for thermal energy storage. Key takeaways included the importance of strong, active communities and platforms that bring together both research and industry.
A big thank you to everyone who contributed to making this event a success, from presenters to organisers to participants. We’re looking forward to seeing you next year!
