…is a good $50 water distiller.
And I’ve come to the conclusion that it doesn’t have one.
We’ve talked about water purification numerous times on the blog, since drinking water is a constant concern here at the Lair. I’m not terribly concerned about drinking water as such, since it is filtered with existing equipment right in the crappy little town nearest where we live. Not a lot of reason to fear the supply will dry up, and even if it does our well water isn’t actually toxic – just really hard and you’ll be dealing with kidney stones after a few years of drinking it*. But we all run our electrical systems on numerous big deep-cycle batteries, which means we also need a reliable source of distilled water. And last month for reasons never fully explained, the one local supply dried up. There’s a whole big shelf of drinking water at the one local food market, and on that shelf there’s a slightly less big empty space where the distilled water ought to be. Lots of people here go through distilled water for the same reason my neighbors and I do, and either the demand suddenly skyrocketed or the supply suddenly dried up. I had to advise Landlady to bring several gallons up from the city to ensure her own supply, and that’s ridiculous.
So okay: I already worry about my lack of a Plan B for drinking water, as you can imagine. Now suddenly my supply of distilled water is uncertain. That brings me back to a subject I have long dismissed: Why don’t I have a distiller?
To reiterate the reason I don’t have a solar distiller, which in my situation would seem on the surface to make the most sense: They barely work at all, their output is minuscule, and the cleanup is constant. For reference, I have a stainless steel cooking pot in which I heat water for washing, and this is what it looks like inside…
That’s calcium laid down on the surface just from bringing the water to a boil: Never mind boiling the vessel dry, which you mostly do in a distiller. Cleanup would be a constant issue.
As would energy usage. As far as I can tell your typical electric countertop distiller requires 800 watts of electricity for several hours just to produce a gallon of water. I’ve got a 600-watt inverter and nobody has that kind of battery capacity. That means burning gasoline in a generator – while you have gasoline.
I go through 2-3 gallons a month on batteries alone for three different installation. If I were drinking it, I’d need a minimum of a gallon a day. Call it 5-6 hours of an 800 watt draw, every day, rain or shine.
A non-electrical distiller such as this one makes claims that even the friendliest reviewers don’t seem able to match. Call it two quarts an hour, either constantly burning propane or tending and feeding a wood fire. Between tending the fire and cleaning the equipment you could make a usable supply of water doing that, if you had next to nothing else to do all day. But if you really needed it, chances are there are other things you’d need to do with your time – like finding food.
I’d like to experiment with these gadgets but they’re quite expensive and so far my research suggests they wouldn’t match their promises or my needs. It’s a concern.
Long time ago I helped operate a still. Alcohol. I can fully understand how much energy it takes to boil liquids, we burnt up a bunch of propane in homemade high pressure burners. Also you have to have some source of “cool” to get the steam to condense efficiently. We had free running water for that. What altitude are you at? I think the higher you are the more energy it takes to get a boil?
This is precisely something I’ve been wrestling with for a while now. Distillation solves a lot – although not necessarily all – problems with water quality. Basic filtering – plain coffee filters to start, then a decent sand and charcoal filter solves much of the issue, then the heat involved in turning liquid into vapor does a good job on all bacteria I’m aware of, almost all viruses (I’m still researching that, but so far it’s good), and the condensate is mineral-free.
I keep coming back to a reasonably basic “moonshine still” and lots (and lots) of firewood. Building a still doesn’t seem that big a deal; after all, if 4th-grade-dropout Billy Bob in deep throes of Depression-era poverty could build a pretty good one with the resources of the 1930s, it should be snap today.
The stoppers, as you point out, are the heat source and the time necessary to procure, maintain and operate that heat source to get enough distilled water out of it in a short enough time to make it practical. I do recognize the very substantial difference between “practical,” “necessary,” and “absolutely mandatory.” Humans can tolerate stuff in drinking water that batteries cannot unless one can live with quite shortened battery life.
I’d suspect there’s a small but significant market for a very simple, basic, 5-10 gallon/day still that’s efficient enough to be worthwhile, even if it’s offered as a kit; by definition, those of us strongly enough interested in it to consider building our own are capable of reasonably complex assembly tasks.
Let me throw out a crazy idea. Part of the formation of hard water scale is a chemical reaction triggered by heat. So don’t heat the water. Instead spray the water cold through a shower head at one end of a sealed box. At the other end of the box is a dehumidifier. The distance between the ends needs to be long enough for the solids to drop to the bottom of the box rather than be pulled into the dehumidifier. This will be helped by the air intake to the dehumidifier being in its the top half. Then attach a hose to the output of the dehumidifier and run it into whatever clean container you want to use. The small unit I have uses 7 kilowatt hours to extract 30 pints of water. Is that a practical amount of electricity?
Ok, my idea is to dig a hole, line with pond liner, plate of glass positioned over said hole (think sliding glass door or shower door). Tilt glass so evaporation runs down glass into a channel (could use pvc with a channel cut into it. And then a collector to receive run off. What do you think? Cheap, easy and should work. Could also have a tilapia farm during non-winter.
If you google “desert survival solar still” you will find all sorts of information on making a solar still. They work slowly, but even if you just get a cup or two a day in the summer, you would probably come out ahead. They also sell similar versions for blue water sailors to store on life rafts. Good luck!
This feels like a circular discussion because we keep having it, yet it never goes anywhere.
Don’t forget that you live inside a world-sized solar powered natural still that (even in the desert) makes more distilled water than you will ever use. Unfortunately you can never be sure when it’s going to operate, so the discussion becomes mostly about collection and storage.
I’m adding to the above anon pit idea using pond liner. You could use a roll of plastic instead of the glass if you wanted to extend the length easily
The estimated cost of this off grid water distiller is $50. Now all you have to do is find somebody how is good at making pots. 🙂
https://offgridworld.com/50-simple-solar-still-makes-salt-water-drinkable/
tk421a, that is really interesting, haven’t seen it anywhere else. Maybe instead of making pots, a source to buy them from people already using this system?
Reverse osmosis will take out those deposits. The problem is that with your water you’d need to replace filters quite often. Winslow has very hard water as well, a friend that lives there said that he tried a RO system, but wound up replacing the filters every month just for drinking water for two people. For him it was simpler (and just as cheap) to buy water in town. RO may work as a backup plan, but you’ll want a lot of spare filters.
Electrodialysis would not require constant filter change, but I’ve never seen anything but industrial size ED’s in use. No one makes a residential unit, which tells me it’s not cost effective. Sorry.
Yeah, I have neighbors who installed RO systems. I don’t know anyone currently using one. They’re expensive in filters, wasteful in water, and generally require more water pressure than I have since I don’t use a pressure pump.
As a relatively new reader, I didn’t know you had had kidney stones. Allow me to relate my own story/solution…
Back in the 80’s I let myself get dehydrated and got one. Several years later, I repeated that twice as I forgot about the last pain episode. Finally, I smartened up and decided I was done with this type of fun and was never going to have another stone. So I set about studying everything I could find on the subject. NOT what popular opinions says, but what the medical texts say.
What I found was that kidney stones are stones(duh)/rocks/minerals and that they are subject to the same laws of mineral precipitation that every other mineral is. As a geologist/geochemist, this is something I thoroughly understand (thank you Dr Misra- my college geochem teacher). So I also dug out the phase diagrams that show how calcium carbonate precipitates out of solution. (CaCO3 is the stone you get unless you are 90 and almost dead anyway). That’s easy. Now to find what shifts the diagram……
Long story short, if you introduce excess Magnesium into the solution, the Mg cation will preferentially grab the carbonate ion making MgCO3 and not letting CaCO3 form. The beauty here is that MgCO3 stays in solution (will NOT precipitate out) at body temperature and is excreted in the urine. And lo and behold, once I knew what to look for, I found the same idea in the medical literature, including in the Merck Manual if you want to look it up yourself. So I began Mg supplements (over the counter) in a does that was like 1/4 the RDA (but it was still 2x or so higher than the research showed was needed to stop CaCo3 stone formation).
And I have been stone free for decades despite living in the kidney stone belt of the US the entire time.
A few years ago, a friend was hospitalized with stones. He had them like BAD. After he got out, I brought up my solution and as he is extremely hard headed told me he didn’t want to hear about it, his dr had him on a prevention pill that insurance paid for. He gave me the name of the pill and I looked it up. Its Mg and B12 (B12 does to the CO3 ion what Mg does to the Ca cation) and nothing else. It works. Its extremely cheap(you can find a small enough does on the shelves so you can break up the pills). Its verifiable in the medical literature so its not just Internet Wisdom.
Go with Desert Rat’s suggestion. Find a large tub, put a catch container in the middle, cover with plastic, place a small weight on the plastic. Put water in tub. Water gradually evaporates, condenses on the plastic, runs down the slope to drip into catch container.
Slow and inefficient, but it will keep you in battery water. Putting a little bit of water in the plastic depression with the weight may help with condensation as it will act as an tiny evaporative cooler.
Scrounge up a few tubs (or line a large, shallow hole with plastic) and it would probably keep you in drinking water.
My father used rainwater for batteries, as it comes out of the sky fairly close to distilled water. I know it doesn’t rain there much, but if you had a plastic barrel to capture your gutter runoff instead of dumping it in the “creek” it might be useful for the batteries. I doubt if a plastic drum would cost you much. If you kept an eye out for one, you might score it for free.
It will pick up some contamination while running off the roof and the gutter, but it won’t have time to accumulate any significant amount.
Joel, I understand and appreciate the problem with evaporating water from a pot. The scale is gross and quickly becomes unmanageable.
There is a simple solution, used all over the world to cool buildings. They evaporate about 90% of the water. What’s left has concentrated the impurities by 10 times and is pretty gross. They flush it down the drain (they call it blowdown), you can dispose of it in the desert.
Since solar power is plentiful where you live, a thermal solar collector, basically a pipe running along the back of some more or less fancy black plate, will heat the water much, much faster than the “survival still” hole with plastic above it. You can probably scrounge one.
Set up a valve from your water supply to the collector and adjust it for a slow drip, a gallon or two in 8 hours. The water that comes out of the solar collector will be as hot as can be. Put that very hot water into the condenser of your choice, whether it be a pit with some plastic above it and a bowl to catch the dripping condensate underneath, or an honest to god heat exchanger where the cold water coming in cools the vapors coming off a pan of hot water. A well cleaned heater core would do.
Every day throw out whatever water is left in the evaporator pan. Since your water is so very hard, you might want to evaporate only 75% or even 50% before throwing out the blowdown.
It will take some scrounging and tinkering, but you are good at that. If you really want seriously pure water, you can run the water through 2 or 3 times.
If you have lots of sunlight why not build a solar furnace?
I think there is enough scrap around here to make one of these. The PDF at the link in the article is the materials list with dimensions.
https://www.motherearthnews.com/diy/home/how-to-make-a-solar-still-ze0z1209zsch
Simple as can be and no reason it won’t work gangbusters where you live.