Towards sustainable water resources: A critical review of evaluating traditional and solar-based desalination technologies and innovations
S. K. Jha, Aritra Ghosh
Abstract
Scarcity of water is a universal problem affecting more than 2 billion individuals, with about 785 million having no access to basic drinking water . Spurred by the population growth, urbanization, and global climate change , meeting this challenge coheres with the UN's Sustainable Development Goal 6 to make water available by 2030. Desalination , which transforms saline water that constitutes approximately 97 % of the global resources of water into fresh water, is progressively critical, particularly in dry and coastal areas . Of the various desalination processes, Reverse Osmosis (RO) stands out due to its energy requirement of 3–10 kWh/m³ and quality of fresh water. Thermal technologies like Multi-Stage Flashing (MSF) and Multi-Effect Distillation (MED) are also utilized but are usually more energy-intensive. The integration of renewable energy sources , including solar, has improved sustainability, with hybrid solar desalination systems minimizing the energy intake by up to 30 %. Recent progress in solar still technologies, such as ceramic magnets and black powder-coated crushed granite for heat storage, has increased productivity by 28 %, attained energy efficiencies of 30.5 %, and reduced payback periods to less than four months. This article overviews solar desalination processes solar thermal, photovoltaic-driven RO (PV-RO), and CSP hybrid systems focusing on technological developments like nanomaterial and advanced membranes. Comparative evaluation of these technologies against traditional technologies weighs technical viability, cost-effectiveness, scalability, and environmental considerations. Case studies from water-scarce locations inform practical experience and issues. The article concludes by reviewing future opportunities, emphasizing innovative technologies and facilitating policy regimes to ensure sustainable, energy-efficient desalination solutions worldwide.