Seasonal solar thermal energy storage using thermochemical sorption in domestic dwellings in the UK

Abstract

The present paper explored the potential of the seasonal solar thermal energy storage (SSTES) system using ammonia-based chemisorption for domestic application in the UK. The dynamic charging/discharging performance of the SSTES has been simulated using the real weather data with the solar thermal collector models, the domestic heating demand model and the chemisorption model. The selection of working salts has significantly influence on the system design and dynamic performance. The CaCl2-4/8NH3 chemisorption can satisfy almost 100% of space heating demand when using low temperature hating facility during discharging stage, however, due to its relatively higher desorption temperature and limited sunlight available in the Newcastle-upon-Tyne the required solar collectors area exceeds the commonly available space of dwelling roof. The NaBr-0/5.25NH3 chemisorption is only able to contribute 18.6% of heating demand because the temperature of the discharged heat cannot reach the required level for most of the time in the heating season. The best scenario studied was using BaCl2-0/8NH3 chemisorption SSTES (45.2 m3 storage volume) combined with low temperature heating facilities and a 30.5 m2 solar collector, which can cover about 57.4% of space heating for a dwelling with a heat loss coefficient at 150 W/K.