solar water distillation

Solar, wind, hydro and other non-fossil sources of electricity.
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John Bozi   1 MW

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Re: solar water distillation

Post by John Bozi » Dec 23 2020 11:17pm

thanks for all the info.

Guys, I think I found my own end to my interest in this exploration. My ideas were that as long as I substitute the lost minerals in my food, then this will be healthy. I couldn't find anything much conclusive. Then I read something more based on findings: ... chap12.pdf

The part that I am most worried about is that: water without the minerals will be pulling the minerals out of you. I am not 100% sold on how that is explained but there are so many medical conditions related it freaks me out.

The second worrying part is the 'aggresiveness of soft water' on leaching whatever it is in contact with.

It appears that drinking distilled water for 'several weeks' is enough to cause numerous problems.

In conclusion, I have bought a solar kettle and will use it to make coffee :lol:

Hope you enjoyed the ride...

john61ct   100 GW

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Re: solar water distillation

Post by john61ct » Dec 23 2020 11:20pm

All that is bulldust really, really thought you'd already figured it out.

but never mind

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spinningmagnets   100 GW

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Re: solar water distillation

Post by spinningmagnets » Dec 24 2020 8:49am

As long as you are eating food, you can drink distilled water with no mineral-leeching effects to your body or health.

We could construct a scenario where you are adrift at sea in a lifeboat, but you have a solar distiller providing all the fresh water you can possibly drink. Even then it would take quite a while for the lack of electrolytes to hurt you.

I was a machinist mate in the Navy on a submarine, and one of my jobs was the distilled water. The steam turbine engine-system provided us with vacuum and waste-heat, and the steam-turbine generator provided more electricity than we could use.

If you take a gallon of water and boil it away (sending it to a condenser, to change back into a liquid), the pot you boiled it in will still hold the solidified salt and mineral scale. Therefore, we have a lot of "flow through", so almost no scale builds up inside the system.

We pull a vacuum so some of the water will vaporize at a lower temperature. We warm the water a little bit, and direct the vapor to a condensing chamber. The resulting drinking water is very pure. The crew drank this water on a regular basis, and i did this for about three years. Some "at sea" deployments lasted as long as a month.

Of course we also drank coffee, tea, milk, etc. We had salt if you wanted to sprinkle it on your food. If your food and beverage intake is low in vital minerals, I firmly believe your body will tell you long before it is a health problem.

john61ct   100 GW

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Re: solar water distillation

Post by john61ct » Dec 24 2020 10:00am

There have been extensive scientific studies show the same. Many fulltiming cruisers drink practically nothing but RO water.

If you were deprived of everything else the effects if malnutrition would kick in long before starting to "leach minerals" from your bones.

Pure urban myth IRL

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John Bozi   1 MW

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Re: solar water distillation

Post by John Bozi » Dec 24 2020 3:20pm

Thanks SpinningMagnets for your real-life experience.


Do you have a link to an RO study? Is all RO filtered the same? I know filtered water filters various things probably not every mineral...

Did anyone check the link I shared? It's long but if you just read the last 2 paragraphs of P.151 it gives you some ideas of the research:
It has been adequately demonstrated that consuming water of low mineral content has a
negative effect on homeostasis mechanisms, compromising the mineral and water metabolism in
the body. An increase in urine output (i.e., increased diuresis) is associated with an increase in
excretion of major intra- and extracellular ions from the body fluids, their negative balance, and
changes in body water levels and functional activity of some body water management-dependent
hormones.Experiments in animals, primarily rats, for up to one-year periods have repeatedly
shown that the intake of distilled water or water with TDS ≤ 75 mg/L leads to: 1.) increased water
intake, diuresis, extracellular fluid volume, and serum concentrations of sodium (Na) and chloride
(Cl) ions and their increased elimination from the body, resulting in an overall negative balance..,
and 2.) lower volumes of red cells and some other hematocrit changes (3). Although Rakhmanin
et al. (6) did not find mutagenic or gonadotoxic effects of distilled water, they did report
decreased secretion of tri-iodothyronine and aldosterone, increased secretion of cortisol,
morphological changes in the kidneys including a more pronounced atrophy of glomeruli, and
swollen vascular endothelium limiting the blood flow. Reduced skeletal ossification was also
found in rat foetuses whose dams were given distilled water in a one-year study. Apparently the
reduced mineral intake from water was not compensated by their diets, even if the animals were
kept on standardized diet that was physiologically adequate in caloric value, nutrients and salt
Results of experiments in human volunteers evaluated by researchers for the WHO report
(3) are in agreement with those in animal experiments and suggest the basic mechanism of the
effects of water low in TDS (e.g. < 100 mg/L) on water and mineral homeostasis. Low-mineral
water markedly: 1.) increased diuresis (almost by 20%, on average), body water volume, and
serum sodium concentrations, 2.) decreased serum potassium concentration, and 3.) increased the
elimination of sodium, potassium, chloride, calcium and magnesium ions from the body. It was
thought that low-mineral water acts on osmoreceptors of the gastrointestinal tract, causing an
increased flow of sodium ions into the intestinal lumen and slight reduction in osmotic pressure in
the portal venous system with subsequent enhanced release of sodium into the blood as an
adaptation response. This osmotic change in the blood plasma results in the redistribution of body
water; that is, there is an increase in the total extracellular fluid volume and the transfer of water
from erythrocytes and interstitial fluid into the plasma and between intracellular and interstitial
fluids. In response to the changed plasma volume, baroreceptors and volume receptors in the
bloodstream are activated, inducing a decrease in aldosterone release and thus an increase in
sodium elimination. Reactivity of the volume receptors in the vessels may result in a decrease in
ADH release and an enhanced diuresis. The German Society for Nutrition reached similar
conclusions about the effects of distilled water and warned the public against drinking it (7). The
warning was published in response to the German edition of The Shocking Truth About Water (8),
whose authors recommended drinking distilled water instead of "ordinary" drinking water. The
Society in its position paper (7) explains that water in the human body always contains
I realise there is a controversy here....

Researching more, This guy attacks the above article. ... lled_water

quite well on precise points... but the problem I have with all this is that everyone seems to have an agenda. The guy critiquing is invested in passive distillation and his writing style is not academic to get some cred on the topic I was hoping for.

This article ... innie%20et. is the opposite but seems to be invested in pure water.
However, its a weak argument to suggest that we should make up this deficiency through water consumption (WQA, 2011). Tap water presents a variety of inorganic minerals which human body has difficulty absorbing (Misner, 2004). Their presence is suspect in a wide array of degenerative diseases, such as hardening of the arteries, arthritis, kidney stones, gall stones, glaucoma, cataracts, hearing loss, emphysema, diabetes, and obesity. What minerals are available, especially in "hard" tap water, are poorly absorbed, or rejected by cellular tissue sites, and, if not evacuated, their presence may cause arterial obstruction, and internal damage (Dennison, 193; Muehling, 1994; Banik, 1989).
When you don't know who to believe, best not change what is working in life. I really want an unambiguous academic piece of writing based on studies. He said she said does nothing to give confidence.

The best thing about this project is that I have learnt about an incredibly divided field....

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jonescg   1.21 GW

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Re: solar water distillation

Post by jonescg » Dec 25 2020 12:27am

A couple of comments. I too grew up on a mixture of town water and rain water, and the rain water never had filters.
So too did many of my friends, until one of them got sick. Really sick. He got a bad dose of Cryptosporidium and/or Giardia - a common parasite in bird shit and occasionally discovered in unfiltered rainwater. It's been 4 years since his bout and he's unable to drink milk as his intestines were more or less wiped clean.

Filter your rainwater before drinking it. I didn't, but I was lucky I guess.

On the passive solar water distillation front, the main problem with it is the evaporation of water actually taking heat energy from the body of water it's leaving, reducing the average kinetic energy of the source container. So the solution is to ensure the volume of water being used as the source of vapour is kept as shallow as practical.

Some clever research into it though: ... 7X15000155 ... 016-1231-9

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John Bozi   1 MW

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Re: solar water distillation

Post by John Bozi » Dec 29 2020 3:29am

Thanks Jones, both why not to drink roof water and tips for shallowness make sense.

Every morning I see on the bottles of rainwater that I have horizontal on the ground I see condensation between them and the grass. I guess that means that the grass is warmer than the air.

My kettle arrived today and I got Chinglish instructions. Good I can use 12 or 24v....


I am running a test on it now on a battery. If it works I am not sad about the $36 AU. Guessing the right click means it will hold the 100C for 5 mins .... just a logic thing if its eggs

unklegrumpknee   10 W

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Re: solar water distillation

Post by unklegrumpknee » Jan 31 2021 7:15am

Distillation is the best. But there is also pasteurization. 140 - 170 degrees. And it needs to be held at temp for a small amount of time.

Someone came up with using a parabolic reflector and a piece of black painted copper pipe. At the discharge end a "valve" that only opens when the water is above a pre-set temperature.

I'm sorry I can't supply link.

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