Thermal energy storage solutions
The scope covers the whole spectrum of application of the thermal energy storage systems, ranging from short run to longer run, as well as from the smaller to bigger sizes:
- Thermal end-uses (space heating, hot tap water, cooling) represent a major share of the European electricity demand with consumption often at peak times. Integration into the building heating system and in the smart electricity grid is a key development aspect, next to the storage materials and technologies. Such storage devices reduces the demand for electricity from the grid at peak times during the day, allowing off peak electricity to be used in the building for satisfying cooling needs during summer and/or heating demand, for space heating and hot tap water at later times. The typical charging power is in the order of 3 kW, for periods of up to three hours. The TES system is conceived modularly. The high volumetric energy density is a basic requirement given its utilization.
- For buildings not connected to district heating and cooling network, a much more compact TES system is needed to optimize and to increase the integration of varying RES . Such systems need much less volume than state-of-the-art technologies, realized with materials that have extremely low heat losses and enable the storage of heat and cold for domestic applications for periods typically up to 4 weeks. Cost reduction is a very important target, as the present solutions are too expensive. The ideal thermochemical TES process should have high reaction heat; Good reversibility; Fast charging and discharging rates; Stable reaction products; Non-toxic, non-corrosive, non-flammable and non-explosive reactants and products; Large-scale availabilities and abundance, affordable price.
The nature of the activities concerns:
- The development of novel phase change materials (PCM) and thermochemical materials (TCM) and components of required characteristics for thermochemical and PCM TES, characterized by low starting TRL (4). The development & adaptation of available heat exchanger and novel reactor designs; design and development of controls and modelling for novel sensors for TCM and PCM, starting from a higher TRL (5).
- Ice cold storage having higher TRL (6).
The achievable storage density (kWh/m3) depends on the technological approach (sensible heat, PCM and TCM) and decreases drastically moving from the component to the system level. Furthermore, with the exception of TCM, the charge of the store decreases with elapsed time. The expected system level storage density measured initially and after four weeks from the charge should be indicated.
The selected projects are expected to contribute to relevant BRIDGE[[https://www.h2020-bridge.eu/]] activities.