Aussie Airdrop Harvests Water From Air, Wins Prize | Hacker News Reader

Aussie Airdrop Harvests Water From Air, Wins Prize

popsci.com.au

32 pointschaostheory23 comments

If it works that well in the desert, then the application has great residential commercial viability--like the aquaglobe without having to refill it!

I'd like to see a scale of it commercialized for us non-farming types so then profits can help a philanthropic mission like bringing low-tech irrigation to third world countries in need.

It's illegal in some places to collect rainwater. I'm sure they'll ban any such methods too.

Would the water produced be like distilled water? If so, it would present health problems to people drinking it on a regular basis, from my understanding.

Would adding salt to the water help to alleviate some of the problems with distilled water?

That's actually a bit of a myth, humans get virtually all of our mineral requirements from our food.

Humans do get nearly all of their mineral requirements from food.

But if you sweat a lot and are drinking a lot of water, and don't take in enough electrolytes, you can quickly get into serious trouble.

This is why factories in the south used to give their workers salt tablets. It is allegedly also why certain soft drinks were invented.

The OP's question about distilled water is valid. But since it seems this is primarily targeted at irrigation, it shouldn't be a problem.

Presumably this will be a slow drip type of irrigation and no minerals will be washed away, so when the water evaporates again everything that wasn't taken away with the plants is still there.

Nutrient loss from crop harvesting can be countermanded with fertilizers. Perhaps organic fertilizers made from the very crops consumed...

"I have done well over 3000 mineral evaluations using a combination of blood, urine and hair tests in my practice. Almost without exception, people who consume distilled water exclusively, eventually develop multiple mineral deficiencies. Those who supplement their distilled water intake with trace minerals are not as deficient but still not as adequately nourished in minerals as their non-distilled water drinking counterparts even after several years of mineral supplementation. The ideal water for the human body should be slightly alkaline and this requires the presence of minerals like calcium and magnesium. Distilled water tends to be acidic and can only be recommended as a way of drawing poisons out of the body. Once this is accomplished, the continued drinking of distilled water is a bad idea."

http://www.mercola.com/article/water/distilled_water.htm

That link is pure garbage. Its every bit as bad as homeopathy. [Edited to remove overstatement.]

How does it work? The article and the video are light on the theory. What water collection mechanism of the Namib beetle is employed by the device? Is the device made of hydrophilic material like the beetle's skin? Or is it purely the geometry of the device contributing to the water collection capability?

I think the mechanism is fairly simple. The article mentions pipes deep under ground. I am assuming they dig deep enough to find permanently cooler temperatures, then they circulate air and water condenses due to the temperature differential. They mention it is self-powered so I am assuming solar cells or tiny wind turbines.

I see two problems with this.

1. You don't have to dig very deep to find the earth is warm. But maybe if the desert air is at 100+F then ground temperatures of 50+F are sufficiently "cool" to condensate water out of the air?

2. Disastrously poor places are not poor due to lack of tech or knowledge. War, corruption and general lawlessness tend to keep them poor. Nifty tech just tends to get broken/stolen/monopolized/regulated to oblivion, take your pick.

But in more prosperous areas this might work. It does seem like it would be a lot of work to dig those in. But perhaps once the initial effort is done, you can just leave them there and forget them. Plant away and don't worry about watering. Perhaps even more areas of Australia will now grow vine grapes.

How do you get the water up from "deep enough to find cooler temperatures" to where the plant roots are? It will not fill the air pipes, so is there some secondary piping system? Or will the plants be able to get the water from there?

Also, I wouldn't call it self-powered if it required wind or solar and those were separate parts of the system. A sailing ship is self-powered, but IMO, an electric car that uses electricity extracted from wind is not.

Couldn't you use a heat pipe to bring cooler temperatures closer to the roots?

Re the earth's warmth, water vapor condenses at the dew point[1], which, depending on the level of humidity, may only be a small temperature difference from ambient.

Here in Florida, with very high humidity, it's not uncommon to get condensation at room temperature on very hot days. If I turn my car A/C down to 60F when it's 85F and dark out, my windows will literally be dripping with water within minutes.

[1] http://en.wikipedia.org/wiki/Dew_point

What happens to the IP of these products? Something like this, if open-sourced, could be incredibly beneficial, but I wonder if this doesn't just allow Dyson to create a business out of this (which is great for the inventor, but is this really helping those who need it most?)

What IP would be present in this device? It just seems like a cleverly-designed condenser - water coolers that refill via humidity condensation are cheap and common.

Is it the fact that it's self-powering? That might be an interesting innovation, but the article doesn't talk about that, it just focuses on condensation, which by itself certainly isn't patentable.

Right, thanks for the analysis. I look forward to seeing the specs for this - I always forget to water and my tomatos are complaining.

Well, you patent it.

Nice contest. It's too bad that the prize is only 10,000 pounds. Maybe one of these start up incubator countries (like Chile) can mimic this idea, with bigger purse.

Did I hear the part about "sacred water supplies" correctly? Are there really situations where religion is preventing access to water?

I think he meant it more in a non-spiritual way, implying its importance as a standard water source.

what would be the effect of having removed the water from the air? I assume some of the local plants are already able to harvest water from the air, so would this mean that there is less moisture in the air available for those plants?

It's a great idea, I just wonder what the side affects are.

Since it can only process a relatively small percentage of the air in a region diffusion should quickly bring the moisture content of exhausted air back up to the ambient level. In summary, the effect will be negligible.

I don't think very many plants can pull water from the air.

And in areas where there aren't any plants that should be even less of a problem.

And I think that much like wind turbines, you'd need a serious lot of these to make a noticeable dent in the atmosphere.

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