People in California are turning to Tatooine-style moisture farming

“Community” what’s that? I’m sorry, I’m american. Either give me something inefficient and expensive but mine exclusively, or give me nothing. /s

As an aside, I have a cousin who works on Ogden CA’s waste water reclaimation plant. They get a crazy amount of water back out of the sewage and are able to treat it and add it into the potable supply again.

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Off the shelf technology.

It’s not suited for rugged individualists on their square of desert, oh well.

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Making sewage water drinkable is far more efficient than desalinization but the technology gained the unfortunate nickname of “Toilet to Tap.” For reasons completely unrelated to safety or science the water districts that do this have to pump the pure, treated water into the ground or a river, then take it back out and purify it again, which takes more energy.

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But… if you’re in an arid area and take the water out of the air, doesn’t that make it more arid??

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flosuz(can’t remember the next bits) posted some cool solar panel/desalination tech, some claim to not even leave brine, just solids.

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This kind of thing looks more interesting.

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This makes me wonder whether grey-water diversion systems have failed to be sexy enough to catch on at scale…

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It’s been years, but I used to do legal work associated with the geothermal plants between Lake and Sonoma County – and those things use a lot of water – when those plants were owned by Unocal and later PG&E, they had the rights to a big slog of the treated wastewater from Sonoma County dating back to the 1960s. It was (20 years ago anyway) a bit source of contention between farmers who were starting to run dry, and the power companies. It was a cheap option for the power companies and Sonoma county because it didn’t require very much treatment.

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That estimate sounded off to me, so I checked the math myself and I think you’re off by a factor of 3600. The problem is that a kW is kJ/s, not kJ/day. So 19,221,000kJ/day should be divided by 86400 s/day, which gives 222.47 kW.

Assuming an electricity rate of 0.10 $/kWh, 222.47kW *24 hrs *0.10 $/kWh = $533.91 per day for 8600L. Which works out to about 6cents/L. That’s in line with the article saying it’s cheaper than bottled water. Still probably not a great use of energy if it’s from coal, but it might be reasonable if you’ve already installed solar.

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Makes me wonder why we don’t bring back the practice of cisterns for drinking water.

Have a fine filter/purification system which takes in some combination of AC runoff, rain water, dew catcher. Just connect the things that are already there, instead of building some fancy new thing.

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Cisterns never went away. People who live in places that depend on rainfall for their drinking water (like Bermuda) usually have roofs that divert rainwater to a cistern for their home’s private use. This moisture-capture tech would basically do the same thing except it would be providing water for people in areas that get far less rain.

Quotes like this don’t exactly inspire a lot of confidence that this system will scale well though:

“This machine will produce water for a lot less than you can buy bottled water at Costco for, and I believe, as time goes on and the price of freshwater through our utilities goes up, I think it’s going to more than pay for itself," he said.

For most Californians the amount of water we drink makes up a trivial portion of our water bills. Nobody goes to Costco to buy water for bathing or cooking or cleaning or watering their gardens. Until the Earth is reduced to a Mad-Max-esque hellscape I can’t imagine this being the most cost-effective way for most people to get a drink.

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Hang on, we’re going as fast as we can…

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About $5,000 installed for 10 liters per day. The output is a little disappointing for the price.

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Yes, I divided by 24 hours, rather than 24*60*60 to take it down to kW seconds.

Still, that is just the energy to liquefy the water. The air containing it also has to be cooled.

In the video, one person said half the output of his 9 kW solar panel gave him 227L of water per (sunny) day. That’s probably enough for a household, if you don’t flush or do the washing too much, or have too many overcast days. That sounds about 260 square feet of solar panel just for water.

For actual farming quantities, either a big array, or Mr Fusion.

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Call it astronaut water

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Not an issue once they finally get around to pick up those power converters at Tosche Station.

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I thought Power Converters was a strip bar?

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