A scalable solar-based adsorption thermal battery for day and night heating in a low-carbon scenario

Abstract

Moisture-based adsorption thermal batteries (ATBs) have the potential to alleviate the temporal and geographic mismatch between heat producers and heat consumers, but realizing practical applications is still challenging, in spite of the huge developments in novel materials and system design. Here, a proof-of-concept solar Trombe-wall (T-wall)-based ATB prototype with honeycomb-design, scalable, and low-cost CaCl₂-based fiber brick with ink (ICFB) sorbents is reported for the first time. The ICFB achieves an outstanding thermal storage capacity of 172.8 kW h m⁻³ and good stability in heat charging–discharging cycles. Importantly, the idea of the solar chimney effect in passive building heating is introduced into the system structural design to pursue optimal thermal output and energy saving. Together with the rational operating strategy, the T-wall-based ATB prototype shows exceptional thermal performance, achieving a heat discharging power density of 1.97 kW m⁻³, a discharging efficiency of 64.8%, an energy utilization coefficient of 0.87 kW h_t kW h_c⁻¹, and an energy consumption coefficient of 1.32 kW h_e kW h_ts⁻¹ reduced by 54.2% in comparison with 100%-electricity use, demonstrating its adaptability and possibility of realizing day and night heating in low-carbon scenarios.