The Water Abundance XPrize winner makes water from air • Hacker News Board

Re: The Water Abundance XPrize winner makes water from air

#71

Post by mchannon » Thu, Oct 25, 2018, 5:23 PM UTC

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 variety of climates. In areas where the mercury has gotten below freezing, for instance, there is no water in the air, and yet, we're supposed to believe these snake oil machines are producing 2000gal/day for $0.02 each, even there.

Re: The Water Abundance XPrize winner makes water from air

#72

Post by dang » Thu, Oct 25, 2018, 5:27 PM UTC

corodra wrote: post #25

It’s an overpriced dehumidifier. Pulling humidity out of the air. It’s not magic. It’s not new. There is water vapor in the air, every middle schooler knows this. They are in Hawaii. An outdoor dehumidifier will work great in a water abundant area. How well do you think a dehumidifier will work in a low humidity area? The places that need water the most. It’s not making water, it’s pulling out the humidity. This is s…

This comment breaks the site guidelines, which ask:

"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

They also ask you not to snark. Could you please review https://news.ycombinator.com/newsguidelines.html and follow the rules when posting here?

Re: The Water Abundance XPrize winner makes water from air

#73

Post by hindsightbias » Thu, Oct 25, 2018, 5:28 PM UTC

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…

There used to be a time when extraordinary claims required extraordinary evidence - particularly when thermodynamics is involved. The dehumidifier business is a multi-billion industry. Why would they need an X-Prize when they're extraordinarily better than the state-of-the-art?

https://www.businesswire.com/news/home/20170927005546/en/3-B...

Re: The Water Abundance XPrize winner makes water from air

#74

Post by kazinator » Thu, Oct 25, 2018, 5:31 PM UTC

stephengillie wrote: post #60

kazinator wrote: post #53

Earlier quoted context omitted.

Better check those last two again; one is about fictional tech from Star Wars , the other likewise about something from Dune .

The problem has been solved for so long that it's used by multiple authors in our culture's fiction.

Science fiction is equally replete, if not more, with technological tropes that decidedly do not exist.

Re: The Water Abundance XPrize winner makes water from air

#75

Post by tomcam » Thu, Oct 25, 2018, 5:32 PM UTC

kazinator wrote: post #54

stephengillie wrote: post #37

Earlier quoted context omitted.

This sounds like Persian Wind Catchers. https://en.m.wikipedia.org/wiki/Windcatcher There's a similar type of building which uses temperature difference to generate condensation within a building, creating a pool of water. The name escapes me at the moment.

> The name escapes me at the moment. Vancouver Condo

...and scene. Might as well just close the thread at this point.

Re: The Water Abundance XPrize winner makes water from air

#76

Post by mchannon » Thu, Oct 25, 2018, 5:32 PM UTC

petermcneeley wrote: post #47

I actually had a discussion on this subject with Phil Mason aka Thunderfoot who has a Phd in chemistry and is the creator of the video that is critical of this announcement ( https://www.youtube.com/watch?v=e3s-xI895zc ) The discussion was about how much work is actually required to condense the water vapor. The fact is that it is thermodynamically possible to MOVE more heat energy (Q) than work (W) applied. The effi…

At 100% humidity, sure. If it's raining, it takes no work to get wet.

I have a unit in my garage that can actually produce water at less than 10% relative humidity, moves a lot more air so it has more chances to actually capture the water, and smokes these other units under price/performance, particularly when tested in a desert. It's not a dehumidifier-based system. It's also cheaper to build.

Email me for details.

Re: The Water Abundance XPrize winner makes water from air

#77

Post by dang » Thu, Oct 25, 2018, 5:32 PM UTC

tejohnso wrote: post #70

sdenton4 wrote: post #43

Earlier quoted context omitted.

The prize requirements limits costs to two cents a gallon, it looked like, so can't be all that bad in the energy front.

"Because the process uses a large amount of electricity, designers paired it with a biomass gassifier, a low-cost source of energy. When the gassifier is filled with wood chips, coconut shells, or whatever biomass is locally available, a process calls pyrolysis vaporizes that material. That makes the system hot and humid, the ideal environment to run the air-to-water machine. Because the process uses a large amount o…

That link looks more informative than the original press release, so we changed the URL from https://water.xprize.org/prizes/water-abundance/articles/wax.... Thanks!

Re: The Water Abundance XPrize winner makes water from air

#78

Post by robotrout » Thu, Oct 25, 2018, 5:35 PM UTC

petermcneeley wrote: post #50

petermcneeley wrote: post #47

I actually had a discussion on this subject with Phil Mason aka Thunderfoot who has a Phd in chemistry and is the creator of the video that is critical of this announcement ( https://www.youtube.com/watch?v=e3s-xI895zc ) The discussion was about how much work is actually required to condense the water vapor. The fact is that it is thermodynamically possible to MOVE more heat energy (Q) than work (W) applied. The effi…

* Not to clutter hn but here are my notes for that discussion: http://www.sfu.ca/~mbahrami/ENSC%20461/Notes/Refrigeration%2... http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/watvap.ht... this shows that its quite large amount Efficiency fridge = 1 / ( Th / Tl - 1) There is actually way more water in the air than 0.04 grams... i think this is because liters not m^3 for 1m^3 there is 30 grams at 30 degrees and 17.3…

> Perhaps this wont work because the MASSSIVE heat sink required

Perhaps not! Thanks for running the numbers.

Re: The Water Abundance XPrize winner makes water from air

#79

Post by mfringel » Thu, Oct 25, 2018, 5:35 PM UTC

corodra wrote: post #25

It’s an overpriced dehumidifier. Pulling humidity out of the air. It’s not magic. It’s not new. There is water vapor in the air, every middle schooler knows this. They are in Hawaii. An outdoor dehumidifier will work great in a water abundant area. How well do you think a dehumidifier will work in a low humidity area? The places that need water the most. It’s not making water, it’s pulling out the humidity. This is s…

By posting this comment, you're saying "I'm a genius, and you're all idiots, because I've figured out this obvious thing that has gone over all of your heads."

Now, you might actually mean that, but it might be more useful to explicitly spell it out in that case.

Re: The Water Abundance XPrize winner makes water from air

#80

Post by comesee » Thu, Oct 25, 2018, 5:36 PM UTC

I don't get it, why don't poor communities build piping from their nearby water sources? People were able to do this 2000 years ago. Why do they need to invent a reverse-entropy machine?