Continuous humidity pump and atmospheric water harvesting inspired by a tree-pumping system
Akram Entezari, Lin He, Oladapo Christopher Esan, Weili Luo, R.Z. Wang, Ruoyu You, Liang An
Abstract
Dehumidification not only regulates the relative humidity (RH) of buildings with reduced cooling costs but also provides a potential drinking water source for residents. Desiccant-based dehumidification has a lower energy consumption than the condensation-based method; however, the former requires successive regeneration of used sorbents and is, therefore, bulky. In this study, by mimicking transpiration in trees, we propose a humidity pump (HP) that continuously dehumidifies rooms by creating a continuous driving force for water wicking. Meanwhile, we investigate the potential of the HP by combining it with atmospheric water harvesting systems. We use activated carbon-lithium chloride composites since they have proven to possess high sorption capacity and strong capillary effect. We develop a small prototype, and our results show that it can maintain the RH between 50% and 70% while producing 1.3–3.25 g water per day. By advancing these techniques, we create an opportunity for developing more energy-efficient humidity regulation and atmospheric water harvesting systems.