Translations:AY Honors/Wilderness Living/Answer Key/12/en

Solar still

A solar still can be used to extract pure water from just about anything that is wet. Start by digging a hole 25cm deep. Place a small container in the center of the hole - this will catch the water. Place damp matter (chopped up cacti, wet leaves, etc.) in the hole around the container, and then cover the hole with a transparent plastic sheet. Weight down the edges of the plastic sheet so that it cannot slip into the hole, and place a small weight (such as a small rock) in the center of the sheet. This weight should be situated directly over the center of the container. As sunlight penetrates the sheet, it evaporates the water from the damp material in the hole. The water vapor rises until it reaches the sheet, where it condenses. As the water collects on the underside of the sheet, it runs downhill to the weight where it drips off, and hopefully, falls into the container. This will even work with urine (but reserve that for a real emergency).