Solar Water-Distillation Units

How Solar Water Distillers Work

• Water needing purification is fed into the holding chamber of the water distiller. Sunlight entering through the transparent material heats up this water until it reaches the vaporization point. This vapor rises, and as it rises it cools. When it hits the underside of the transparent cover material, it condenses. This condensate trickles into a tray that collects the now purified water. The water is funneled out into a receiving container.

Materials

• The main part of a solar water distiller consists of a holding basin and a cover. This cover is typically made of a transparent material. Plastic and fiberglass are commonly used, but glass is the most efficient. Glass retains less energy than the other two materials, thus making more heat energy available for distillation. The basin is typically rectangular and made out of an opaque material, usually concrete or a concrete compound; portable ones may be made of a lighter material. A rubber or plastic hose is attached to a plastic collection tray. The clean water is typically collected in plastic jug, such as those typically sold for use in water coolers.

Reasons to Use a Solar Water Distiller

• Solar water distillers are particularly well suited for Third World and developing countries which have a scarcity of potable water and limited access to electrical power. While the small scale of solar water distillers makes them unsuitable for use in producing clean water for a large community, they are a reasonable potable water solution for individual households. Solar water distillers only produce a small volume of clean water, the average being two liters a day. This is more than adequate for the drinking water needs of a small family. People in developed countries may want to invest in a solar water distiller if living in an eco-conscientious manner is an important objective. Solar water distillers reduce a household's carbon footprint because they do not require an external power source.

Disadvantages of Solar Water Distillers

• Solar water distillers do not produce a large volume of potable water, so they will likely never be an effective solution for large communities. It is also difficult to keep insects out of the holding tank. The distilled water is missing minerals added to municipal water supplies for health reasons; fluoride, for instance, is added to prevent tooth decay. As a hypotonic solution, distilled water has the ability to leach some minerals and vitamins from the body.