Solar powered desalination – Technology, energy and future outlook

Growing water demands have led to rapidly increasing desalination installation capacity worldwide. In an attempt to lower carbon footprint resulting from high-energy consuming desalination processes, attention has shifted to using renewable energy sources to power desalination. With solar irradiation ample in regions that heavily rely on desalination, solar powered desalination provides a sustainable solution to meeting water needs. The compatibility of each desalination process with the solar technology is driven by whether the kind of energy needed is thermal or electrical, as well as its availability. With rapid advances in solar energy technologies – both photovoltaic and solar thermal, there has also been growing interest in coupling solar energy with desalination, with a focus on improving energy efficiency. In this review, the most recent developments in photovoltaic powered reverse osmosis (PV-RO), solar thermal powered reverse osmosis (ST-RO) are discussed with respect to membrane materials, process configuration, energy recovery devices and energy storage. In addition, advances in new materials for solar powered membrane distillation (MD) and solar stills in the past two years have also been reviewed. Future outlook considers the use of hybrid renewable energy systems as well as solar powered forward osmosis and dewvaporation. Solar powered desalination systems have been analysed with emphasis on technological and energy consumption aspects.