Evaluation of dehumidification and energy-saving effects for a passive dehumidification system combined with energy recovery ventilation

Passive dehumidification strategies utilizing renewable energy sources and moisture-buffering materials offer effective solutions for reducing indoor humidity and cooling demands for air-conditioning systems in hot and humid areas. We developed a passive dehumidification and solar collection (PDSC) system that incorporates energy recovery ventilation (ERV), named PSE (PDSC & ERV) system. Here, a basic passive dehumidification theory based on the nonequilibrium thermodynamics of the proposed system was developed. Three numerical models of a residential building operating with various systems (exhaust-only ventilation, ERV, and PSE systems) were constructed using THERB for HAM software, and their accuracies were validated. To simulate the performance of the PSE system in cooling air-conditioned conditions, THERB for HAM software was coupled with a heat pump characteristic model, which can predict the water content condensed by the air conditioner during cooling. The indoor environments of the PSE system and the other three systems (exhaust-only ventilation, PDSC, and ERV) were simulated using this coupled simulation method. The simulation results showed that the PSE system had the highest dehumidification effect, reducing the latent and total heat loads by 49.1 and 10.9 %, respectively, compared to the exhaust-only ventilation system.