Penn Engineers Discover a New Class of Materials That Passively Harvest Water from Air
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I'd recommend reading the article before trying to make a comparison.
When water condenses on surfaces, it usually requires either a drop in temperature or very high humidity levels. Conventional water harvesting methods rely on these principles, often requiring energy input to chill surfaces or a dense fog to form to collect water passively from humid environments. But Lee and Patel’s system works differently.
Isorhermal (unpowered) water condensation from capillary action isn't the interesting part, (and the article title doesn't really make that clear), but the potential ease of water extraction after condensation is interesting - and the original paper makes it clear in the discussion that that part isn't done yet and isn't guaranteed
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Yeah, science communicators need to not evaluate themselves by the same metrics as newspapers and magazines. Getting people to click and share should not be the metric of success.
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The entropy of a little water mixed with air is higher. As with anything that mixes a little.
Condensation is exothermic, though, so the material will heat up slightly
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Yeah, why pretend physics are being broken when we could instead discuss the fact that we're one step closer to having moisture farming as a profession!
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You realize the amount of water is constant, right?
Not if Nestle has anything to say about it
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I am fairly certain they are referring to the fact that we are already removing water from the fresh water cycle, and this could remove even more. For example, global warming combined with draining the aquafers means less water in the cycle as it was drained into the ocean and isn't beaing replenished as snow/glaicers.
Yes, the total volume of water on the planet isn't being changed by that shift, but the amount of freshwater is.
Nobody will remove water from ambient air in relevant amounts. Roughly 0.5 % of air is water vapor, a total of something like 10'000 km³ liquid water. This is replaced (residence time) about once every 10 days, so roughly 1'000 km³ daily.
Say we extract 10 km³ (10'000'000 m³) daily, enough for roughly 10 million people (including all industry, zero recycling of the water etc.). By that time you deal with 1 % of earths atmosphere every day. May I remind everyone how absurdly costly in any conceivable way that would be? You would rather lay a few pipes and purify sea water at a tiny(!) fraction of the cost.
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Nobody will remove water from ambient air in relevant amounts. Roughly 0.5 % of air is water vapor, a total of something like 10'000 km³ liquid water. This is replaced (residence time) about once every 10 days, so roughly 1'000 km³ daily.
Say we extract 10 km³ (10'000'000 m³) daily, enough for roughly 10 million people (including all industry, zero recycling of the water etc.). By that time you deal with 1 % of earths atmosphere every day. May I remind everyone how absurdly costly in any conceivable way that would be? You would rather lay a few pipes and purify sea water at a tiny(!) fraction of the cost.
They won't drain the aquifers, nature will replace that much water!
They won't cut down all the forests, the trees will just regrow!
They don't have to cycle the entire atmosphere to cause havoc. Pulling the moisture out in local areas that already have lost aquifers and ice in the mountains is the obvious issue. Plus, you don't know the cost in the long run, it could end up being fairly cheap.
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Trees harvest it from the ground, not the air.
Trees absorb MOST of their water through the soil, but are absolutely capable of absorbing water directly into their leaves. Google "Foliar uptake"
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They won't drain the aquifers, nature will replace that much water!
They won't cut down all the forests, the trees will just regrow!
They don't have to cycle the entire atmosphere to cause havoc. Pulling the moisture out in local areas that already have lost aquifers and ice in the mountains is the obvious issue. Plus, you don't know the cost in the long run, it could end up being fairly cheap.
People were able to (and at some places did) cut down every tree WELL before they had power tools and even saws. Just with axes. The comparison is laughable.
No, massive air moving structures can not be cheap. Neither building nor operating them.
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Cool, just have to go to Tosche Station to pick up some power converters first.
