Medium to long term thermal energy storage system with embedded heat pumping capability

Solutions developed

Based on preliminary analysis, the participants aim to achieve a round trip efficiency for power-to-storage-to-heat or heat-to-storage-to-heat of 140-160% depending on temperature level with a storage density of 0.5 GJ/m³ at lab-scale level, while addressing cost-effectiveness. At material level they aim for a 20% increase in energy density, while using sustainable and affordable materials and production methods. By addressing industrial applications, the current project aims at decarbonising the third most emitting sector in the EU - manufacturing, which is responsible for ~20% of the total GHG emissions in the EU. Developing a versatile and energy dense TESS facilitates deployment within the industrial sector, further enhancing sector coupling capabilities such as cascading industry sectors or coupling industrial parks with district heating, paving the way to flexible and fully integrated energy systems.

Main results

The use of intermittent energy sources such as wind and solar incur fluctuations in energy production which lead to gaps in renewable energy availability. Using electricity at peak production to generate thermal energy becomes feasible only if thermal energy storage provides means to decouple generation from production. Many industrial processes generate large amounts of thermal energy throughout the year as waste heat which reduces energy efficiency. In some industrial setups, waste thermal energy is rerouted in industrial parks, however, temperature levels, demand schedule and processes proximity rarely play in favour of this circular approach. Sector coupling opportunities are reduced due to a mismatch between sector demand schedules. The project aims to develop a medium-temperature, medium-to-long-term Thermal Energy Storage System (TESS) with built in heat-pump capabilities provided by a hybrid approach using TCM & PCM materials.