UP-FLEXH is an international research project developing and validates a flexible industrial energy system combining high-temperature heat pumps, thermal energy storage, and solar thermal technology to deliver low-carbon heat up to 400°C.
A key component in the project is a new type of high-temperature heat pump with minimal environmental impact. It captures low-temperature waste heat that industries already produce and upgrades it to the high temperatures many production processes require. The heat can be stored in molten salt, so it can be produced when electricity is cheap or the sun is shining and used when the process needs it. The project brings together KTH Royal Institute of Technology (coordinator), Enerin, Kyoto Group, RPow Consulting, MG Sustainable Engineering and Absolicon.
Project overview
| Project period | December 2024 – November 2027 |
|---|---|
| Project status | Ongoing |
| Funding | Clean Energy Transition Partnership (CETPartnership), Joint Call 2023. Absolicon receives funding from the Swedish Energy Agency. |
| Project coordinator | KTH Royal Institute of Technology, Sweden |
| Absolicon’s role | Leads the work on combining the system with solar heat and on analyzing how it can be used in real industrial plants. |
Background and challenge
Around two-thirds of all energy used by European industry goes to process heat. A heat demand for steam applications, drying, cooking, distillation and more. Today, most of this heat still comes from burning fossil fuels, making industrial heat one of Europe’s largest sources of CO₂ emissions.
Heat pumps are an efficient way to electrify heat. Instead of turning electricity directly into heat, they reuse existing low-temperature heat and deliver several times more heat than the electricity they consume. But today’s commercial industrial heat pumps typically reach temperatures around 150°C, while many processes, for example in breweries, paper mills and refineries need heat at 200-400°C.
Electrification also brings new challenges. Electricity prices vary widely from hour to hour, and large new electric loads can strain the grid. Solar heat is cost-effective but cannot cover all of an industry’s demand around the clock on its own. To make fossil-free heat work in practice, industry needs systems that combine several heat sources with storage, and that can adapt to both the production schedule and the energy market.
Absolicon’s contribution
Absolicon leads the consortium’s work on how the UP-FLEXH system can be combined with solar heat, and how it can be integrated into real industrial plants. This builds on Absolicon’s experience from designing and delivering solar heat installations for industrial customers.
Absolicon also leads the techno-economic modelling of the system in different industrial cases, showing how it would perform and what it could cost in real conditions.
Expected results and impact
UP-FLEXH will build and test a complete system in a test facility designed to replicate real industrial conditions. The system includes a high-temperature heat pump, molten salt heat storage and solar heat, and will be tested for at least 400 hours under different temperatures, power levels and operating modes. The heat pump uses helium as its working fluid – a gas that is non-toxic, inert and has no climate impact if it leaks.
The project is expected to contribute to:
- A first-of-its-kind heat pump able to deliver heat at up to 400°C, well above what commercial heat pumps reach today
- Lower CO₂ emissions from industrial heat, by reusing waste heat and increasing the share of renewable energy, including solar heat
- Lower and more predictable heating costs, by producing and storing heat when electricity is cheap
- Studies of how the system can be used in real industries, and roadmaps for taking the technology to market around 2030
- A stronger knowledge base for combining solar heat, heat pumps and thermal storage in industry
Funding
This research is funded by CETPartnership, the Clean Energy Transition Partnership under the 2023 joint call for research proposals, co-funded by the European Commission. Absolicon receives funding covering 70% of its eligible project costs from the Swedish Energy Agency.
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