Ok I know it sounds silly in ways but, inspired by recent events in central california and The original star wars movie (moisture farmers).
Just how effective could dehumidifiers be at harvesting water for emergency use. I was just speaking to a friend in Lake Isabella area (mountains of eastern kern county) and apparently people are short selling houses to get away because wells are running dry at an alarming rate. I see several units available at TarWalLoweDepot that pull a few gallons a day (probably only under ideal conditions). Even a gallon a day would be a big deal to someone with nothing to drink. Is there any meaningful benefit here for plunking a dehumidifier (or 3) on top of a plastic drum/tank as an emergency water source?
You can only pull water out of the air if it’s there to begin with. Maybe those home dehumidifier units can pull out three gallons a day when there’s 100% humidity, but if you’re in a drought, the air is probably pretty dry, too.
It’s also not safe, you’d have to boil or treat it in some way.
You’d need to treat any water from a dehumidifier as if it had some kind of mold or fungus in it.
Also, if you’re going to do that, rather than invest the money in a dehumidifier that’s going to heat the house, might as well just divert the condensate hose from your AC into a bucket.
Speaking of which, the dehumidifier is going to be fighting with the AC. It’s going to heat the house, the AC will be running to cool it and they’ll both be dehumidifying.
Putting the dehumidifier in the basement will probably give it the best chance of having almost no impact on the AC and drawing the most moisture out of the air.
The efficiency would be significantly reduced in arid conditions. But maybe if solar powered…? I guess it would still be cheaper to tank in water (unless that was not possible for some reason, such as impassable terrain or surrounded by enemy).
I’ve wondered if **Dune **'s water traps would really work in such a dry place.
You could also extract moisture from foliage. This has been billed as the way to survive in the desert.
Dig a smallish hole in the sand, out in the sun. Put a small cup in the bottom center of the hole. Put any foliage you can find, smushed up, in the hole around the cup. Put a transparent plastic sheet over the hole. Poke the sheet down just slightly in the center, so any water that condenses on the under side of the sheet will run down towards the center and drip off into the cup below.
Then the moisture in the foliage will steam up the hole, condense on the underside of the plastic, and drip into the cup.
You would definitely have to account for the expense of buying and maintaining the device. I can’t seem to keep one running in *my *basement for more than a few years.
(Although as noted upthread, many people are already operating AC’s, which also take moisture from the air.)
I also second the notion that the water is probably not potable without treatment, except in emergencies. Although the fungus and whatnot in the line may not *necessarily *be pathogenic, who knows what evil…
It probably wouldn’t be a concern on a brand new machine, but I’d be concerned about one that’s been running for years (like, say, an air conditioner). But just to be safe, I’d treat it, especially if you’re in such dire circumstances that this is your only water source. Do you really want to end up with diarrhea of vomiting when you don’t have any more water.
I am sure there are some but I have never seen one. In areas prone to liquefaction during an earthquake they might be a real hazard. That said I always wanted to have one.
While I do love mine and I don’t know the difference between being on a slab and having a crawlspace, you have to understand that having a basement introduces a whole host of problems. If it rains, your basement can (and probably will) flood, being the biggest problem. If that’s common, you learn to keep everything off the ground. You have a sump pump to maintain, gutters have to be cleaned to keep water away from the structure, foundations crack*, clutter builds up and plenty of other things I’m not thinking of.
Remember, depending on the location, you’re essentially setting your house into a swamp and constantly fighting to keep the water out and away from the concrete as much as you can.
Probably not as big of a deal in the SW as it is in the Midwest or NE.
*Of course if you have a crawlspace that means pilings that can fail and if you’re on a slab that means you have footings. Both of which aren’t exposed so fixing them is probably a lot more expensive and it’ longer before you know you have a problem. OTOH, my plumbing doesn’t freeze and I have a great place for my mechanicals.
When I first moved to LA from Ohio (and having grown up with basements there), while I was looking for apartments, one landlord’s wife (who was a native californian) said they had this one “weird property with a second floor, except it was BELOW the first floor” :eek:. She was genuinely confused when I asked if she meant it was a basement.
I was assuming putting them outside thus making them less prone to fighting AC as well as not “drying out” the room they are pulling from.
I am not envisioning this as a substitute for a well or anything, more like a way to not have to drive 20 miles to the nearest store for some drinking water.
I have an uncle who has a beachfront house in LA, and yet actually has a basement. He built the house himself, and is quite proud of it. I’m not sure what extents he has to go to to keep it dry, but I imagine that it’s pretty extreme.
According to Energy Star, the median efficiency (measured in L/kWh) is less than 2 L/kWh (that site rates nearly 400 models, listing the most efficient first). So, you are about 2kWh worth of electricity per gallon (and that is probably with air near 100% RH). I see that electric rates in CA are about $0.17(Lordy, you guys pay a lot for electricity!). This would work out to about $0.34 per gallon, although I don’t even think you’d get anything if you are dealing with 22% RH. Per the manufacturer’s info, you need dewpoints above 38F for them to work.
I think some homes in California are built into hills with the ground level floor being the public one, with the living room, kitchen and so forth, and bedrooms on a lower level.