A comprehensive review on rotary desiccant wheel systems: the future of smart building climate control

This comprehensive review examines the development and potential of rotary desiccant wheel systems (RDWSs) for energy-efficient and sustainable climate control in smart buildings. Driven by the increasing demand for alternatives to conventional HVAC (heating, ventilating, and air-conditioning) systems, RDWSs advanced desiccant materials, such as silica gel composites, and innovative geometrical designs to achieve superior dehumidification and energy performance. The review explores the evolution of RDWS technology, including advancements in system configurations, hybrid integrations, and material innovations. Experimental and computational studies are analysed to assess key performance factors, encompassing energy consumption, moisture removal rates, and regeneration efficiency. The potential for integrating renewable energy sources, such as solar and waste heat, further enhances the sustainability of RDWSs. While significant benefits are evident, challenges remain in optimising operational parameters, scalability, and economic feasibility. Addressing these limitations through continued research and innovation will enable RDWSs to revolutionise indoor air management and contribute to global sustainability goals. This review provides valuable insights into the current state and future prospects of RDWSs for achieving energy-efficient and eco-friendly climate control in smart buildings. According to the recent literature, the dehumidification COP of RDWSs is in the range of 0.3–0.4 at a regeneration temperature of 50 °C and a fan speed of 2 m s–1. In addition, at a regeneration temperature of 60 °C, the moisture removal/release rates are given to be 4.55/1.16 and 3.97/0.42 kg–1(d.a.) for fan speeds of 2 and 4 m s–1, respectively.