File:Portable Solar Still.jpeg

A solar still is a tool used to filter dirty water or collect water vapor from the air. A solar still uses energy from the sun to distill water. Dirty water is added to the solar still which has clear walls to allow sunlight to pass through. The light energy which hits the water is converted into thermal energy which heats the water. As liquid water evaporates into water vapor it collects on the top inside wall of the still. The cooler air outside the still reduces the heat of the water vapor caught in the top which begins to condense. Using a weight, a low point is made in the top of the still which is where the water vapor gathers and condenses into liquid water. The liquid water falls and is collected in a container. A solar still uses the natural processes the earth uses to make freshwater. I wanted to make a still which could be easily moved around without having to be disassembled. I used a plastic container, plastic wrap, and pvc pipe to make the still. With the pvc pipe I built a rectangular frame which holds a cup to collect the condensed water. After putting the pvc frame inside the plastic container I used the plastic wrap to create a box shaped container which is nearly airtight. I was trying to create something as close to a closed system (allows energy in and out but not matter) as possible. The closer to a closed system, the less water vapor is lost because of leaks. The still is extremely light weight and efficient at distilling water.