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The Water Abundance XPrize winner makes water from air

fastcompany.com

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Re: The Water Abundance XPrize winner makes water from air

#81

Post by 08-15 »

azernik wrote: post #65
08-15 wrote: post #44

Earlier quoted context omitted.

> has actual numbers for power input per liter of water Where did you find that? All I could find is "0.8-1.8kW/hr" for a machine with capacity with a capacity of "30gal/day". This is complete nonsense, "kW/hr" is neither energy nor power nor energy per volume of product. And if it's power, why does it vary? I'm going to read it as 1.8kW, with a capacity of 30 US gallons (113l) per day. My dehumidifier from the hardw…

Generally a lot of electrical appliances are advertised with kW or W actually meaning kW-hour and W-hour (and yes, this is awful, but it's pretty standard). So your interpretation as 1.8kW is about right. It varies, as does output, because (as the numbers mention) this all varies wildly by atmospheric temperature and humidity. (By the way, running the numbers I'm seeing it as 62.77L/kW vs. 50L/kW, which is a 25% impr…

groan

So when they write kW/hr, they mean kWh/h, which is kW, because they expect readers to be confused. But if that's the power of the machine, it shouldn't vary. Just like my car produces 70kW, not "7-70kW/hr depending on road conditions". This machine would run a max power all the time, wouldn't it?

> 25% improvement

Serves me right for trying to compute in my head. Qualitatively, it makes no difference, though: they claim a 100% improved efficiency over the competition, and they are nowhere close. The 25% difference may indeed be purely to scale; bigger machines (whether from this company or the hardware store) tend to be more efficient.

Re: The Water Abundance XPrize winner makes water from air

#82

Post by mamon »

mchannon wrote: post #62

Pretty disappointed with their choice of winner. Using refrigeration to maintain a dewpoint means that this appliance is pretty impractical below 50% relative humidity. Or in other words, this thing only makes water when you probably don't need water. Blow some nice 90 deg F 20% humid air past those coils, and you'll be blowing out a lot of 80 deg F 25% humid air out on the other side, getting bupkis for actual produ…

>> this thing only makes water when you probably don't need water.

Living in California recently I constantly see the weather forecast claiming 70-90% humidity and yet the area is basically a dessert with almost no rain. I suppose there are many more areas in the world like that.

Re: The Water Abundance XPrize winner makes water from air

#83

Post by drewm1980 »

mchannon wrote: post #71
joshe wrote: post #48

I don't know why this is attracting so much bitterness. If anyone is informed about water, it would be great to get a little more context, for example what other solutions like desalinization and other dehumidifiers cost in energy and dollars. (Yes, obviously nothing is going to be as cheap as putting a pipe in a river.) For example their FAQ says they use less than half the power of their competitors. That seems lik…

If you remember back to the perpetual motion machine, that was supposed to produce more electricity than it consumed, you'll capture the mindset detractors like myself have. But look, our PMM is producing this many volts! And it works great on paper too! I haven't seen any data or reports to show this competition actually tested built units and measured both their water output and energy consumed, and did so in a var…

RE "no water in the air blow freezing", that's not true. In the mountains you can hang your towel up to dry at night. It freezes, then dries through sublimation. Ever seen funny smooth ice formations?

Re: The Water Abundance XPrize winner makes water from air

#85

Post by mchannon »

drewm1980 wrote: post #83
mchannon wrote: post #71

Earlier quoted context omitted.

If you remember back to the perpetual motion machine, that was supposed to produce more electricity than it consumed, you'll capture the mindset detractors like myself have. But look, our PMM is producing this many volts! And it works great on paper too! I haven't seen any data or reports to show this competition actually tested built units and measured both their water output and energy consumed, and did so in a var…

RE "no water in the air blow freezing", that's not true. In the mountains you can hang your towel up to dry at night. It freezes, then dries through sublimation. Ever seen funny smooth ice formations?

This sounds like a koan:

"If there is a frozen towel in the mountains, is there water in the air if there is no one there to measure the humidity it produces?"

Assuming there were millions of frozen wet towels in such conditions, any sublimated towel ice would rapidly drop back out of the air as frost.

Re: The Water Abundance XPrize winner makes water from air

#86

Post by organsnyder »

mchannon wrote: post #62

Pretty disappointed with their choice of winner. Using refrigeration to maintain a dewpoint means that this appliance is pretty impractical below 50% relative humidity. Or in other words, this thing only makes water when you probably don't need water. Blow some nice 90 deg F 20% humid air past those coils, and you'll be blowing out a lot of 80 deg F 25% humid air out on the other side, getting bupkis for actual produ…

"Using refrigeration to maintain a dewpoint"... so, a dehumidifier?

Re: The Water Abundance XPrize winner makes water from air

#87

Post by [deleted] »

jpm_sd wrote: post #19
travisoneill1 wrote: post #17

2 cents a liter is not close to feasible for any sort of agricultural or industrial use and is an order of magnitude more expensive than residential tap water. Seems like cool tech, but I can't see how this is a solution to any type of water shortage.

I believe the general idea is to provide drinking water where there is no pre-existing "residential tap water" infrastructure.

[deleted]

Re: The Water Abundance XPrize winner makes water from air

#89

Post by foofoo55 »

Articles all state "from air" but half the system uses pyrolysis (high heat to gasify without flame) to extract water from biomass.

See also comments on slashdot from someone claiming to be from All Power Labs, the gasifier supplier:

https://science.slashdot.org/story/18/10/22/079250/a-device-...

Re: The Water Abundance XPrize winner makes water from air

#90

Post by jandrese »

ortusdux wrote: post #15

Here is the website for one of the winners: http://www.skysource.org/ From what I can glean online, the 150 gal/day unit costs $18k usd + $150-$300 in electricity a month if run 24/7 at $0.10Kwh. Ignoring electrical costs, it would take 1581 days to reach $0.02/liter. In that time you would use up $7.5-15k in electricity. The best estimate I could find is that the average US household uses 240 gal a day. A friend of…

I'm going to guess that if you need to spend $18k on equipment to get your water then you probably aren't going to blow through 240 gallons a day.

150 gallons could be quite a lot of fresh water for a small remote village that otherwise lacks a good fresh water source. Useful for drinking and cooking, but not used for bathing or irrigation. I assume the system could be powered by a reasonably sized solar array.

On the other hand, given the cost of this setup it would probably be a lot easier and cheaper to install water filters.

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