The SWS-HEATING project will develop an innovative seasonal thermal energy storage (STES) unit with a novel storage material and creative configuration, i.e. a sorbent material embedded in a compact multi-modular sorption STES unit. This will allow to store and shift the harvested solar energy available abundantly during the summer to the less sunny and colder winter period thus covering a large fraction of heating and domestic hot water demand in buildings. The targeted benefit of this next generation solar heating technology is to reach and overcome a solar fraction of 60% in central/north Europe, reaching 80% in the sunnier south of Europe, with a compact and high-performing STES system at low cost, realising solar- active houses throughout EU.

The SWS-heating system is based on a multi-modular sorption seasonal thermal energy storage (STES) unit, using novel sorbent materials of Selective Water Sorbents (SWS) family characterised by superior heat storage density compared to the state of the art, making it possible to drastically decrease the storage volume with negligible thermal losses. These materials are employed in a sorption module with dedicated heat exchangers. Solar heat is provided to the storage modules by high- efficiency evacuated tube solar thermal collectors. Intensive research activities will deal with an advanced vacuum combi- storage tank, with the aim to further minimise thermal losses. A smart and adaptive control will be developed for efficiently managing heat supply and demand sides, including advanced features aiming at user-friendliness. A building prototype will be commissioned including the SWS-heating system, which will be tested and validated in Germany and Sweden and proof all challenging objectives.

The project also includes dissemination and communication activities to ensure outreach of its results. Moreover, exploitation activities include long-term deployment path development through a technology roadmap.