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Post by jeff on Mar 31, 2016 13:01:25 GMT
Evaporative technology can be used to supply humid air to a greenhouse, then have more humidity added, with heat, followed by condensation, to collect freshwater supplies, possibly w/o expensive filtration... Seawater Greenhouses Produce Tomatoes in the Desert by Renee Cho|February 18, 2011 According to the World Health Organization, about 20 percent of the world’s people live in regions that don’t have enough water for their needs. With the global population increasing by 80 million each year, a third of the planet will likely face water shortages by 2025. This looming water crisis is inextricably linked to food production because agriculture accounts for 70 percent of all fresh water used, and obtaining irrigation water in arid regions has serious environmental impacts. Drilling wells can deplete groundwater, and desalination is energy-intensive and leaves behind concentrated brine. blogs.ei.columbia.edu/2011/02/18/seawater-greenhouses-produce-tomatoes-in-the-desert/
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Post by Deleted on Apr 2, 2016 3:27:57 GMT
There was as greenhouse scheme that seemed to work well in the news some years ago. Problem was, it was being fought over by two parties, both of whom claimed it as their invention. It used surface sea water, and desalinated it, and condensed the exit air to make freshwater for irrigating the greenhouse. I forget the particulars. As long as the legal fighting was going on, no one put any money into it.
EDIT: After reading the page Jeff provided the url to, this is the same greenhouse plan i remembered. However, the internet site for the greenhouse in Oz is dead. I am guessing that $2 million for a greenhouse is just too much for the greenhouse to pay back.
With a small otec plant drawing up cold deep water, that water can be used in condensers to drip water out of the air.
I'd expect we'd all like some of our living space dehumidified.
If we don't drink it, we can wash with it, or give it to the plants.
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Post by jeff on Apr 2, 2016 9:48:19 GMT
Q/D simplification, but the initial cool/moist air comes from an evaporative cooler/water chiller, which can be all plastic... secondary evaporative coolers use heated water, then use the chilled brine in condensers, from the first phase...
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Post by Deleted on Apr 4, 2016 16:25:03 GMT
First, does anyone know why the site in Oz failed? What we need is an informed decision, and we have no info of the real-world implementation, operation, or failure of this system. The only data i can recall specifically about the incoming water use is it was salt water and surface water.
Two, i have seen commercially made "swamp coolers" in action, i have also watched commercial cooling towers for 400 ton chiller plants for over a year. The swamp coolers tend to clog up, both types of cooler grow mold/algae. The approved media is pricey, and it needs replacing because it's uncleanable. The reefer unit used asbestos fiberboard, prolly eventually replaced with fiberglas board, you cannot power brush either. The chemicals used to prolong the media life by killing biologics in the evaporation media may doom the plants in the greenhouse too. And then there's the outflow of the chemicals after two layers of evaporation banks, in the air, in the brine, AND in the condensed freshwater, which might be considered air and water pollution (real possibility, unknown data, see first paragraph above).
It's a wonderful idea on the face of it, but it's been done, it failed, and we don't know why. If it costs $2 million to fail (the Aussy site), does anyone want to throw away another $2 million to find out why it failed? Rather than wasting money on fake studies and art contests, "that other seasteading site" could have sent someone down to interview the employees there, look the greenhouse over, and find out what went wrong.
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Post by jeff on Apr 4, 2016 23:34:46 GMT
No real way to know, but the bigger the budget, it seems, the more likely to fail at the declared mission. I'm not looking at throwing a lot of funds at the above idea, just that it uses the same principles, and could be a viable small-scale solution. I'm planning a greenhouse, as part of my Gulfstead, might as well try for the distillation system. (shrugs)
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Post by Deleted on Apr 5, 2016 1:55:43 GMT
I am all for the water distillation, all for lots of fresh water, all for a garden, all for efficency, wish i could do a greenhouse, but somehow i get the feeling i said something wrong. I appologise if i did.
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Post by gordien on Apr 5, 2016 3:47:26 GMT
I just ordered a Fontus solar water condenser through Indiegogo. I don't know when to expect deliver, but I'll let you know how it works when I get it (gallons per sunny day).
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Post by jeff on Apr 17, 2016 4:29:07 GMT
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Post by jeff on Apr 17, 2016 8:49:51 GMT
Concept I just came up with. Small, solar-powered fandraws air up through the middle, while warm humid air is drawn down the outside pipe. Condensation forms on the pipe walls and drips into the tank, then can be drawn up, through an additional tube.
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Post by johngalt on May 11, 2016 3:06:29 GMT
Have you guys ever read the book "Sailing the Farm" In there he talks about a simple solar still that he used to distill water. The process is simple and the design is scalable. Heres a version you could even use on a life raft in an emergency.
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Post by jeff on May 13, 2016 18:41:25 GMT
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Post by Deleted on May 13, 2016 19:07:25 GMT
I bought the paperback "Sailing the Farm" several years ago, somehow i got two of the same book. The pdf is welcome also, thanks.
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