The La-Flex project will further develop latent thermal energy storage (LTES) to make heating and cooling systems more energy flexible. Energy flexibility is the ability of the energy system to receive and deliver energy as it is produced and consumed. Fossil fuels and hydropower are flexible energy sources, because they can produce energy when there is a need for energy. Solar and wind power, on the other hand, are not flexible energy sources. As the world moves away from fossil fuels to solar and wind power, we will lose this energy flexibility, and there will be an increasing need for energy storage. Thermal energy storage is important because thermal energy consumption accounts for 50% of global energy consumption. LTES is based on phase change materials (PCMs) that store energy in a phase transition and can store heat or cold with high energy density and in a narrow temperature range. This technology can be used to store cold in industrial freezing processes, heat for heating office buildings, or store and utilize excess heat in data centers.
La-Flex's main goal is to improve the monitoring and control of LTES. This is to be able to exploit flexibility, and to be able to operate in reserve markets. This will be done by developing real-time state of charge measurement and precise thermal power control, which will make LTES easier to integrate into control systems for optimal energy management.
In La-Flex we have designed and dimensioned a latent thermal energy storage pilot with a phase change material with a melting temperature of 16°C. This pilot will be installed at the Technical University of Denmark (DTU) campus Risø, og will be used as a cold storage to a data center. In this pilot we will test new sensors to determine the state of charge, and we will test new control systems to minimize grid stresses and energy costs. The cold storage will be able to charge during the night when the electricity price and outdoor temperature is low, and will be able to discharge during the day when the electricity price and outdoor temperature is high. We are interested in the response time and the discharge duration of the storage, as this will be important to show that these types of latent thermal energy storages for ancillary services.
The project is led by SINTEF Energy and brings together research and industry partners from Norway, Denmark and Germany, including the Technical University of Denmark (DTU), the Technical University of Applied Sciences Würzburg-Schweinfurt (THWS), as well as Cartesian, AInergy and KLP Eiendom. The project's advanced state of charge measurement and thermal power controller will facilitate LTES in power flexibility and reserve markets, improve system performance and promote grid stability in the face of variable energy supply from renewable sources.
Heating and cooling constitute about 50% of the global energy consumption, and with the increasing reliance on solar and wind electricity via heat pumps, the demand for effective energy storage solutions has become imperative. Latent Thermal Energy Storage (LTES) with Phase Change Materials (PCM) can serve as an asset for flexible heating & cooling supply for buildings as well as for industry.2 State-of-charge (SoC) detection, i.e., a determination of the remaining capacity available in a thermal energy storage, is crucial for optimized storage operation schedulers and allow a precise thermal power control (TPC). Thus, the integration of instant and reliable technique for determining the SoC and a precise TPC in a model predictive control (MPC) system would pave the way for optimal operation of grids coupling different energy sectors –including power-to-heat and waste heat utilization from industry. La-Flex's main objective is to optimize
LTES by enhancing its controllability. Integrating instantaneous SoC and TPC in MPC systems, La-Flex will facilitate a flexible integration of LTES in power flexibility and reserve markets, tackling intermittent supply and electrified heating/cooling demands, appliable in all climate zones. La-Flex will be carried out by the Norwegian – Danish – German partnership formed by the research partners SINTEF Energy Research (SER), Technical University of Denmark (DTU), and the Technical University of Applied Sciences Würzburg-Schweinfurt (THWS); and the industry partners Cartesian (CAR), AInergy
(AIE) and Kommunal Landspensjonskasse Eiendom (KLP).
