A thermodynamic review on solar stills

Abstract

The supply and quality of water is still a problem in undeveloped or developing nations. Researchers from different countries have developed various distillation or desalination techniques among which solar distillation is a good option to obtain fresh water. Solar stills are promising technologies to meet the freshwater demand; hence intensive efforts are also made day after day to improve their design for a high productivity yield along with a cost reduction. In the present work, solar stills have been investigated based upon the thermodynamic approach for the first time in literature. A review has been done to highlight the research gap for a scope for future studies and thus, this study focuses on various designs of still and their heat transfer mechanism. Solar stills are evaluated over significant performance parameters such as; design, cost, energy and exergy efficiency, productivity, portability, reliability, and sustainability. Potential challenges of solar stills along with future prospects are discussed. This review also provides potential techniques of performance improvement along with the techno-economic feasibility of solar stills. Therefore, the present study is a gateway to the professionals and new entrants to get much detailed information about solar stills as well as it suggests some potential research work for the future.