Thermal energy storage is an important technology for renewable energy systems and energy efficiency. By improving the effectiveness of thermal storage, the effectiveness of all renewable energy technologies that supply heat can be improved.
Particularly for solar thermal systems, thermal energy storage is essential. To reach high solar fractions, it is necessary to store heat (or cold) efficiently for longer periods of time. Until now, no cost-effective compact storage technologies are available to do this. For high solar fraction systems, hot water stores are expensive and require very large volumes of space. Alternative storage technologies, such as phase change materials (PCMs) and thermochemical materials (TCMs) are available on a laboratory scale. However, more research and development is needed before these technologies can be developed into commercial solutions.
The overall objective of this annex is to develop advanced materials and systems for the compact storage of thermal energy. This can be subdivided into eight specific objectives:
- to identify, design and develop new materials and composites for compact thermal energy storage,
- to develop measuring and testing procedures to characterise new storage materials reliably and reproducibly,
- to improve the performance, stability, and cost-effectiveness of new storage materials,
to develop multi-scale numerical models, describing and predicting the performance of new materials in thermal storage systems,
- to develop and demonstrate novel compact thermal energy storage systems employing the advanced materials,
- to assess the impact of new materials on the performance of thermal energy storage in the different applications considered, and
- to disseminate the knowledge and experience acquired in this task.
A secondary objective is to create an active and effective research network in which researchers and industry working in the field of thermal energy storage can collaborate.
For further reading see the Annex 29 website.