Solar desalination chimneys: Investigation on the feasibility of integrating solar chimneys with humidification–dehumidification systems

Abstract

The feasibility of integrating a solar chimney with a humidification–dehumidification desalination system resulting in a solar desalination chimney is examined in this work using combined validated mathematical models. In the proposed system, the solar energy is used to create buoyant hot air that flows through a humidification and dehumidification system. A small turbine can be housed in the chimney to provide energy for pumping water if there is sufficient airflow. This integrated solar desalination chimney uses solar irradiation as an energy source for buoyant air motion and might not require additional energy input. Data available in the literature for experimental solar chimney setups were examined to evaluate the potential of this novel desalination approach which utilizes solar energy. A validated humidification–dehumidification model is used to investigate desalination capacity. Based on the integrated model, a large-scale solar chimney power plant in Manzanares, as an example, could operate efficiently with a turbine providing power to operate the desalination system and provide freshwater for over 800 households. Moreover, numerical simulation shows that small-scale integrated solar chimney desalination systems could be placed on the roof of a residential building and produce about 600 liters of freshwater daily to satisfy freshwater of a household.