The lack of access to safe drinking water is one of the biggest challenges facing humanity in the 21th century. Despite the collective global effort that has been made, the drinking water sources of at least 2 billion people are faecally contaminated, resulting in more than half a million diarrhoeal deaths each year, with the majority occurring in developing countries and in children under five years of age.
To address the need for safe drinking water, a variety of technologies have been developed and exploited since the 19th century. However, conventional technologies to provide drinking water (chlorination, ozonation, UV lamps, etc.), although effective, present limitations that impede their global application. They are often chemically, energetically, and operationally intensive and focused on large systems that require considerable infusion of capital, engineering expertise, and infrastructure, which limits their application for the prevention of waterborne diseases in the most vulnerable regions. These shortcomings have led to rapid research and development of advanced alternative technologies to provide water intended for human consumption at low cost, low energy usage, and low environmental impact. One of these alternative methods is solar disinfection, which is recognised by the World Health Organization as one of the most appropriate methods for producing drinkable water in developing countries.
On the other hand, regarding the high energy consumption required for treating water in conventional drinking water treatment plants and the global energy crisis driven by the increasing demand for energy, the depletion of many oil reserves and emission of large amounts of greenhouse gases, a sustainable drinking water supply technology cannot be achieved without considering the energy required in the treatment process. In this regard, solar energy is the most abundant renewable energy source, and coincidentally, it is most abundant in the regions that need clean water and electricity. Thus, if properly optimised, technologies integrating solar energy could address the lack of access to safe drinking water and electricity.
This work, which has been published in Chemosphere, has been authored by Dr. Natalia Pichel, researcher at the IMDEA Water Institute and two researchers belonging to the IDEA Group at University of Jaén. In this article, they summarise the current knowledge of the major issues and challenges relating to the lack of access to safe drinking water, and provide a detailed, intensive review of conventional drinking water treatment technologies. In addition, this work highlights the emerging research directions on potable water treatment, with emphasis on solar treatment methods.
You can read the article here.