TESconcrete – Innovative materials for large-scale energy storage systems

In Austria, a large part of the total energy demand is used for space heating and domestic hot water. With regard to the increasing share of renewable energy resources for district heating systems, there is a growing discrepancy between heat demand and supply, which can be compensated by the usage of underground large-scale thermal energy storage systems. This thermal storage technology promises to be a key technology for decarbonising our heat supply systems in the future due to its flexible application possibilities for short-term and seasonal storage, its attractive underground integration possibilities in urban environments and its relatively low costs in construction and operation (“Econmies of Scale”). However, this technology currently still requires considerable technical and economic optimisation potential. The objective of the “TESconcrete” project is therefore the development of innovative high-performance concrete formulations for direct use in new types of prefabricated elements. The elements are used as multifunctional facing formwork, which assumes sealing, thermal insulation and load-bearing functions. Due to the high degree of prefabrication of this construction method, a considerable reduction in construction time is achieved, the risk of construction errors is reduced, and high quality of the components is achieved. The development of prefabricated elements enables the conception of universally applicable storage types.In addition, an evaluation of the interaction with the thermo-mechanically loaded environment (soil), which forms the supporting structure together with the concrete structure, will take place. First prototypes are being developed and tested in the laboratory. In this way, a holistic view of the new type of large-scale thermal storage structure is achieved and thus a rapid market entry is enabled besides the material technology developments. This will secure Austria’s technological leadership in the field of underground large-scale thermal energy storage in the future.