How to Build a Solar Still
Solar water distillation has been around since before we ever showed up on the planet. It is one way that nature cleans and redistributes water . The solar still mimics nature by exposing water to solar heat and re-condensing the cleaned water; but the solar still speeds the process and collects the water. The sun warms the feedstock water in the still until it evaporates. A cooler surface above the evaporation condenses the water and directs it into a container using gravity. This eliminates salts, toxins and pathogens. Water from a solar still is as pure as it gets.
Other People Are Reading
Things You'll Need
- 8' x 8' sheet of clear plastic
- Shovel
- Trowel
- Eight-foot boards, four
- Bowling-ball-sized rocks, eight
- Baseball-sized rock, one
- One-gallon plastic water container
- Funnel
- Duct tape
- Flexible plastic tubing, one eight-foot length
Instructions
-
-
1
Dig a round hole, five feet in diameter and three feet deep. In the bottom of the pit, dead center, dig out a smaller hole big enough to hold your water container.
-
2
Insert the stem of the funnel into the mouth of the water container. Insert one end of the plastic tube into the mouth of the water jug alongside the funnel. The tubing needs to reach to the bottom of the container. Secure the funnel tube assembly with duct tape, ensuring the funnel is facing straight up, and the tube is not bent or otherwise obstructed. Fit the jug assembly into the small hole at the bottom-center of the pit.
-
-
3
Fill the pit around the jug with untreated water, urine, anything that will give off water when it is heated. Do not cover the bottom with solids as if you were mulching. That will slow evaporation.
-
4
Pull the free end of the plastic tubing to the outside of the pit, and tape the end to prevent dust entering. Stretch the clear plastic sheet over the pit, with the sides equidistant from the edge of the pit. Secure the edges by laying the boards along them, then placing one rock at the end of each board. The plastic sheet should be flat and tight, and the tubing should exit from the sheet along the outside of the pit.
-
5
Place the baseball-sized rock in the center of the sheet, directly over the funnel. Press down slowly on the rock until the whole plastic sheets "tents" downward a few inches. Your plastic should be shaped like a shallow, inverted cone.
-
6
Leave the completed solar still to the sun. The sun will evaporate the moisture inside. That evaporated moisture will rise to the plastic sheet, where the lower surface temperature will cause the water to condense into droplets. The droplets will slide down the slope of the inverted cone of plastic, toward the "point," where they will fall into the funnel and collect in the jug. You can take the tape off the outside end of the flexible plastic tubing, and take a drink.
-
1
References
Resources
- Photo Credit desert 8 image by Dusan Radivojevic from Fotolia.com
