Opportunities for solar water desalination worldwide: Review

Water desalination is increasingly becoming a competitive solution for providing drinking-water in many countries around the world. The desalination of saline water has been recognized as one of the most sustainable and new water resource alternative. It plays a crucial role in the socio-economic development for many communities and industrial sectors. Currently there are more than 14,000 desalination plants in operation worldwide producing several billion gallons of water per day. Fifty-seven percent are in the Middle East and Gulf region where large scale conventional heat and power plants are installed. However, since they are operated using fossil fuels, they are becoming expensive to operate and the pollution and greenhouse gas emissions they produce are increasingly recognized as harmful to the environment. Moreover, such plants are not economically viable in remote areas, even in coastal regions where seawater is abundant. Many areas often experience a shortage of fossil fuels and inadequate and unreliable electricity supply. The integration of renewable energy resources in desalination and water purification is becoming more viable as costs of conventional systems increase, commitments to reducing greenhouse gas emissions are implemented and targets for exploiting renewable energy are set. Thus, solar energy could provide a sustainable alternative to drive the desalination plants, especially in countries which lie on the solar belt such as Africa, the Middle East, India, and China. This paper explores the challenges and opportunities of solar water desalination worldwide. It presents an extensive review of water desalination and solar desalination technologies that have been developed in recent years and the state-of-the-art for most important efforts in the field of desalination by using solar energy, including the economic and environmental aspects.