Solar water treatments take advantage of natural cleansing processes found in nature and enhance them for more efficient results. Compact and even portable solar units are popular at the household level. They may be a good treatment option for developing nations with an abundance of sunny days because they are inexpensive and require almost no investment or infrastructure.
Solar distillation involves putting unpurified water into a container, evaporating it using the sun’s rays, and condensing it into a separate container. Most contaminants such as salts, heavy metals, and microbes stay behind in the unpurified water container, which can be periodically discarded.
Solar disinfection uses the Sun’s ultraviolet rays to kill pathogens. A plastic or glass bottle of untreated water is placed on a roof or a corrugated iron surface. Given enough time and sunlight, ultraviolet light in combination with high temperature will kill most viruses, bacteria, and protozoa.