In tropical climates, a rising demand for active air-conditioning leads to a strong increase of electricity consumption. Compared to the energy demand for the sensible cooling of air the high humidity (in the order of 20 g water per kg dry air) in the tropics results in a significantly high air-dehumidification load. Handling the dehumidification load and sensible cooling load separately can reduce the electricity demand for air-conditioning considerably if the dehumidification is driven by heat energy (e.g. solar thermal or waste heat) instead of electricity.
At the Solar Energy Research Institute of Singapore (SERIS), an experimental two-stage air-dehumidification system consisting of a membrane unit and an adsorption based desiccant unit, has been installed and analysed. The membrane unit pre-dehumidifies the ambient air, which is then further dehumidified and simultaneous evaporatively cooled by an Evaporatively COoled Sorptive (ECOS) dehumidification and heat exchange unit. The aim of this study is to evaluate the dehumidification performance of the two-stage air-dehumidification system under tropical climate conditions and different operating parameters such as air flow rate and regeneration air temperature. ... mehr