Effect of glass salt deposition on indoor environment and building energy performance in salt-fog climate

The salt deposition alters the thermo-optical performance of building glasses in the salt-fog climate, but the impact of salt deposition on indoor environment and building energy consumption remains to be elucidated. This study conducted a systematic investigation into the heat flux through envelopes, the indoor thermal and daylight environments, and the building energy consumption in different thermal climate zones. The convective heat transfer flux (CHTF) remained relatively constant regardless of the deposition amount, and the discrepancy was greater in the Hot Summer and Warm Winter (HSWW) and Cold zones, but less in the Temperature and Hot Summer and Cold Winter (HSCW) zones. The transmitted solar radiation (TSR) exhibited a decline in various zones with the deposition amounts, with salt deposition showing the greatest impact in HSWW zone. Additionally, the CHTF and TSR were linearly related to the deposition amount, with salt deposition exerting a greater influence on TSR than CHTF. The salt deposition enhanced the indoor thermal comfort in all climate zones during summer, as well as that in HSWW and Temperature zones during winter; however, the indoor thermal comfort in Cold and HSCW zones during winter was worsen. Concurrently, the indoor daylighting effect also deteriorated. The salt deposition reduced cooling energy consumption, but led to higher heating and lighting energy consumption, and both the reduction and growth were proportional to the salt deposition amount. It reduced the building energy consumption in regions with high cooling demand (e.g., HSWW zone), while simultaneously increased the building energy consumption in regions with high heating demand (e.g., Cold zone).