Solar water still

I'd like to make a good solar water still. I was thinking of something for purifying the water from rain barrels along my house and channel it into drinking water containers. Any good ideas out there?

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RT-1014 years ago
A Solar Water Still is the Answer.
The following process may appear redundant, but its cyclical nature is how Mother Nature works to cleanse your rain into drinking water. Simply put: Use solar energy to evaporate dirty water into vapor, then condense the water vapor, then collect it as potable water and drink it.

Use the greenhouse affect to make this distilled water. The sun's radiant heat is transmitted through your tent-like greenhouse which uses clear, cheap polyethelyne plastic that completely seals the tent's inside from the outside world. People of yore, used to use window glass and metal framework to build their greenhouses. This was very costly, took a lot of work and was quite time consuming.
Once the sun's rays enter the tent's plastic cover as plain daylight, it generates heat which then naturally turns spectral energy from a visible form to an invisible form known as infrared energy. This infrared energy or heat (like an electric oven) evaporates the rain water that you poured into a light-weighted, shallow kid's bathing pool at the bottom of the tent. Greenhouses trap the sun's heat that way and warm up the trapped air inside the tent. So the sunlight gets transmitted through the clear plastic material and gets trapped as heat that can't get out and just keeps accumulating, making the tent's inside air hotter and hotter. 
Throughout the day you'll notice that this heated air will make your kiddy-pool's dirty water dissappear through evapration into the air in the form of invisible water-vapor. When night falls, you'll see the clean inside-roof of your tent start to collect water droplets and then start to rain inside your completely enclosed tent. This rain is pure distilled water ready to drink.
Catch this pure water using a clean kiddy-pool located several feet above your rain water pools. The several feet of space is needed to let the hot air completely circulate freely over the dirty waterpool  and evaporate it.

So to recap, during the day the sun acts to evaporate your dirty water in a completely enclosed greenhouse of polyethylene plastic sheeting. This evaporated water is sponged-up by the hot air inside the greenhouse. Then at night the evaporated water and air contact the tent's cold outer walls and forces the air to release its water-vapor content by condensing it into water droplets onto the cold plastic surface. After awhile, it literally starts to rain pure drinking water droplets from the inside roof of your plastic tent. Neat isn't it!
A conventional electric oven uses electrical resistance to transform electric energy into heat energy and transfers it via conduction, convection and infrared. We use the conduction to boil water. Some new electric ovens use energy that only heat up the food we cook, not infrared, which would heat up everything.
Satweavers7 years ago
I've been thinking about a solar still for Burning Man. How can you live for a week, slathered in sunscreen without bathing? This would maximize water savings by reusing grey water at the campsite. The idea is, shower after sundown, collect the bath water, put it in your solar still. The next day, in the blazing sun of The Playa, your bath water is sterilized and warmed and ready for your next bathing. The product is clean, even free of microorganisms. You could drink it. Look at: www.solaqua.com/solstilbas.html
GaryGary10 years ago
There are some plans for solar stills here that might be place to start:

robbtoberfest (author)  GaryGary10 years ago
Thanks for the great comments and link.
Ive seen on survivor shows where they take a tub, put water in it, then cover the tub with saran wrap. Then they put a rock in the middle of the plastic wrap, over a collector. The sun evaporates the water, but it hits the plastic and condenses into water, rolling towards the rock which is down, and falling into the collector. Is that what you meant? The collector could be substituted with a pipe, and everything else with more durable supplies. A tube could run from the rain barrel to the bottom of the tub?
robbtoberfest (author)  Weissensteinburg10 years ago
yes yes, sounds very good! Need to add some kind of float valve for the incoming water to the tub.
As long as the tub is placed at the right hight, only a certain amount could be allowed in at a time.
What a coincidence! I swear I didnt see this before I posted that


Thats the exact same concept I described.