Decentralised solar-based water treatment – Bridging the last mile to water security in low- and middle-income countries?

While significant progress has been made to ensure universal access to safe drinking water, limitations associated with the implementation of centralised water supplies has hampered bridging the “last mile” to safe water access for all in developing countries. The use of decentralised solar-based water treatment systems, such as solar pasteurization and solar disinfection, offers a unique opportunity to treat alternative water sources and provide access to safe water in low- and middle-income countries. These solar-based interventions have been shown to be cost-effective, environmentally friendly, scalable, and culturally acceptable. This review will focus on advances in solar-based water treatment systems and the innovative ways these systems can safely be used, in combination with traditional water treatment methods, in developing countries.