Solar-driven hygroscopic-material-based absorption thermal battery for global heating decarbonization

Hygroscopic-material-based absorption thermal battery (ATB) shows great application potential in solar heating systems due to its high performance and zero-global-warming-potential refrigerants. A solar-driven ATB system is established in an actual building for the first time. The field tests indicate that the solar-driven ATB achieves continuous heating with condensation heat recovery, yielding record-breaking performance metrics: an energy storage density of 414.1 kWh/m³ (1109.8 kJ/kg) and an energy storage efficiency of 1.21. The overall efficiency (from solar radiation to heating) is as high as 0.64. Additionally, the global potential analysis of heat storage and heat decarbonization for solar-driven ATB demonstrates its wide application prospect. Besides, the comparison with photoelectric-driven heat pump highlights the advantages of solar-driven ATB in terms of efficiency, cost, service life, safety, and environmental friendliness. Our findings can bridge the significant gap between science and engineering applications of ATB technologies, providing a promising solution for global heating decarbonization. © 2025 Elsevier B.V.