So, it turns out that if you leave plants outdoors in containers for a couple of weeks of dry, hot weather, it is not good for them. Of course, one can set up automatic irrigation systems, but these are tedious and often ugly.
So.
The MaxCo. Solar-powered Waterless Plant Waterer consists of a modest solar panel which charges a battery. When sufficient charge is accumulated, a small air-pump is turned on, compressing air into a reservoir. Once the reservoir has reached about 30 atmospheres of pressure, the pump turns off and the now very hot reservoir is allowed to cool to ambient temperatures.
Once the reservoir's temperature has fallen to within a few degrees of ambient, an outlet valve at its base is opened. From this outlet is expelled a small volume of water - water which was present in the compressed air but which has precipitated out. This water, of course, falls into the soil around the plant.
The cycle repeats itself, each time squeezing a few ml of water from the air, and keeping your pot plant nicely moist.
That is all. This idea now ends.-- MaxwellBuchanan, Aug 02 2016 Pretty much this idea but on a bike. http://www.treehugg...ter-out-of-air.html [2 fries shy of a happy meal, Aug 02 2016] Put me down for thirty units.-- 2 fries shy of a happy meal, Aug 02 2016 [+] a boon for potted planters.-- FlyingToaster, Aug 02 2016 I don't think any liquid water will condense out from the humid air unless you drop the temperature below the atmospheric value, so I don't think this idea will work quite as described.
If, after the compressed gas has cooled, you let it expand back to atmospheric pressure then the temperature will fall below the atmospheric value and you should be able to retrieve some condensate.
Can't you just use a solar powered dehumidifier?-- EnochLives, Aug 02 2016 ^ [link]-- 2 fries shy of a happy meal, Aug 02 2016 A natural gas powered waterer would work fine. Plus it would be a nifty little light at night. One would need a coiled capture tube to cool exhaust gases, allowing condensed water from combustion to drip plantward.-- bungston, Aug 03 2016 //A natural gas powered waterer // Ah, but if you're going to run gas power to each plant pot, that adds to the hassle; as does having to replace gas canisters. The aim here was to have something that you just stick in the pot and forget about.-- MaxwellBuchanan, Aug 03 2016 I used to look after a building air compressor (shop air for a dozen labs or workshops ). It did produce lots of water, but it was an oily yellow whitish product with stringy black dirt floating in it. I wouldn't mind flowers watered with such stuff, but would have second thoughts about food watered with it.
There was a lot of it at certain humid times and the condensate was piped to the sewer.
----
/ ... and keeping your pot plant ... /
Oh I get it now. Thought you were serious-- popbottle, Aug 03 2016 The math that debunks Fontus also debunks this, I think. Compressing air is pretty inefficient, probably comparable to the TEC Fontus "uses".-- notexactly, Aug 05 2016 And when you vent the air, vent it through an air motor geared to help drive the compressor.
I wonder how efficient you could get this?-- scad mientist, Aug 08 2016 One clarifying question [Max]. How much real estate did you have allocated for the equipment to water each plant?-- scad mientist, Aug 08 2016 I was hoping that a 6" x 6" solar panel would suffice.-- MaxwellBuchanan, Aug 08 2016 awesome!
I figured out once how many solar panels it would require to run a dehumidifier, then water a lawn, as a kind of eco-functional way to avoid xeriscaping. I am a libertarian yet i thought this might be more popular than lawn watering rationing at places like California. I do not remember the calculations, yet it looked like you could keep a lawn and trees alive with just solar powered dehumidifiers. I have an urge to say "roof size" yet how large a roof?
also it being California i thought a famous person should have a lush green pleasure garden watered entirely with photovoltaic dehumidifiers-- beanangel, Aug 08 2016 Using the sun's heat to drive the compressor (Stirling engine?) may be more efficient than the multiple conversions involved in a PV and electric motor system.-- BunsenHoneydew, Aug 09 2016 random, halfbakery