Advances in air-dehumidification membranes for cooling applications: Critical analysis of membrane performance and system optimization

Space cooling consumes about 6.5% of the total global energy consumption. Conventional cooling using vapor compression cycles have been historically used due to their excellent performance; however, the use of hydrofluorocarbons limits their usage in today's world due to their adverse impact on climate change. As a result, separative membrane-based air cooling is emerging as more efficient and environmentally friendly; it uses membranes to separate the latent and sensible cooling process. This review aims to give a general overview of membrane dehumidification technology, analyze the state-of-the-art membrane systems, guide future research efforts and assess the current barriers in membrane-based air dehumidification processes. First, analysis of the different process configurations is carried out to establish the required membrane performance in terms of permeance and selectivity. Secondly, the most promising membrane systems and their performance are summarized and the key challenges and limitations at various scales are identified. Finally, a perspective on innovative approaches to address these issues is presented.