Hong Kong is a subtropical coastal city with high humidity, which leads to paramount importance of indoor humidity control. With the rising concern on the control of relative humidity, gas desiccant dehumidification system has been increasingly adopted in commercial and industrial buildings to offer a comfortable and hygienic environment for the buildings occupants. Prior to the technical visit to H Zentre, a sharing session about the gas desiccant dehumidification system was held at the Towngas Headquarters. Ir Sammy Kong, Senior Business Development Manager from Towngas, introduced the latest development of dehumidification technologies and the award-winning invention “Integrated D-PAU”, which integrates the desiccant wheel into the primary air handling unit, supplemented with the use of solar thermal system to achieve further energy saving.