Now we buy around 50 of these and I can take a shower.
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at $150 per 3 liter per day, if this material has a reasonable cycle duty life before needing replacing or dropping in efficiency, then it is very very reasonably priced, especially since the technology requires no additional energy input. the process doesn’t seem to effect the zirconium MOS very much, so it looks like it will have a long operational life.
no additional energy input is needed. this entire system appears to use a reasonable level of passive heat absorption (1 kW per square meter). I don’t think there is any waste heat other then natural passive absorption and radiation, the condenser might be using a micromesh or some other smart material for condensing at a much greater temp range.
that is a good question. is that consistent output or rare theoretical upper limit? makes a HUGE difference.
yeah, promising direction and design, i’ll be curious to keep an eye on actual implementations and how they fare.
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Now we have to invent C-3PO to talk to it.
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I’m curious about the quality of the water produced. Presumably it is similar to distilled water but are there airborne pollutants that could also be condensed out along with the water?
I’m still wondering whatever happened to Dean Kamen’s water thingy that was supposed to change the world by allowing people to get clean water from dirty, with reasonably low power. Big publicity when it was unveiled, now many years have gone by and haven’t heard a peep about it.
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This has some more details:
The team first tested their materials in a controlled environment at 20 per cent humidity and 95 degrees Fahrenheit, probably daytime temperatures and humidities near Uncle Owen’s farm. The setup sucked up .24 litres of water per kilogram of MOF after 70 minutes, which is around a cup of water. After running some tests, the team built and tested a proof-of-concept prototype with a 5 centimeter by 5 centimeter MOF layer and a solar powered condenser, which they tested on the roof of an MIT building. Their prototype can harvest 300 ml of water per kilogram of MOF, said researcher Eugene Kapustin from the University of California, Berkeley, but they only used 1.5 grams of the stuff. They still squeezed out around .2 kilograms, or a little under half a pound of water, at the end of the trial.
Okay, they proved the theory works, but they should scale it up a bit to make sure that the engineering works. I’m not sure that they’ve done the step of getting the condensed water out of their solar cooker, or if they just weighed their MOF before and after and called it a day.
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Those numbers are fucked. They pulled 200 grams (≈ 200 cm³ = 200 mL) of water from 1.5 grams of MOF? Over how many days?
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Urine and feces are processed in the thigh pads.
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Forget the Spice trade. The real money on Arrakis is in deodorizers.
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Unless you’re the Kumquat Häagen-Dazs, that’s for Reverend Mothers only. It’s full of FDS! (F–ing Deadly Stuff.)
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Doon is a much better, shorter book.
why not both?
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seems off because they are discussing weight, not volume. talking about weight in this context makes little sense, after all you can go to the store right now and buy a gallon of water ~8.35lbs in a plastic jug that weighs <60 grams.
Not seems off, is off. Water in liquid phase has a density of very near to 1 g/mL (the units in SI were originally defined by the density of water, although the definitions have since changed), so the conversion to litres is a no-brainer. The point here is that 1.5 g of MOF doesn’t enclose an empty volume of 200 mL the way a plastic film would, and that the figures they give for the amount of water they can recover in general is 300 mL/kg of MOF (which will equal about 300 g H2O/kg of MOF).
Do you see the mismatch?
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Thanks. I was all in support of you questioning the numbers, and your argument makes perfect sense, I hadn’t caught the 300 mL/kg of MOF figure. The 300mL/kg per (day/cycle?) figure actually makes 1.5 grams of MOF mean something otherwise, without that context a 1.5 gram matrix could encompass a very wide range of volumes. a graffine matrix is are perfect example of a low weight to high volume matrix.
To my addled brain, talking about the matrix weight doesn’t make any sense unless it is in the context of a conversion like the one you provided above.
Presumably per cycle, which is per day. Their intake phase is at night, and they close the enclosure during the day when they force the MOF to give up its contents, so that portion of the operation is fixed to whatever the matrix holds at that point, which is presumably at or below its maximum carrying capacity. I wouldn’t see that maximum figure changing too much - the MOF is in effect a porous ceramic that traps the water by adsorption, so 300 grams of water per 1,000 grams of matrix makes sense - the surface area of adsorption isn’t going to vary a lot per given weight of matrix. (Edit: the surface area is mainly internal to the matrix.)
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thanks for the additional info.
i don’t really know enough to say one way or another about that, but it makes sense.
I do know just enough about matrix like graphine, to know that the internal surface area dramatically increases as you lattice the molecules to create their ultra-light weight high volume matrices. these matrix have close to the maximum internal surface area possible for the structure they create. i don’t know enough about what they are doing in this application to know how that applies.
Great another vaporware product! 
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OK, this makes better sense (per Hello Tatooine! An unpowered device can harvest water vapor in a desert in Ars Technica):
Because the demonstration prototype was a small device, it only captured a small amount of water, but the potential is there. Scaled up to one square meter, this version would harvest roughly 0.2 liters per day.
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