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If you find this interesting, there are other technologies either proposed or used to collect atmospheric water. Air wells: https://en.wikipedia.org/wiki/Air_well_%28condenser%29 Fog collection: https://en.wikipedia.org/wiki/Air_well_%28condenser%29
If this became widespread wouldn’t this negate some of the positive side-effects of creating more light reflection on earth? https://www.bbc.com/future/article/20190220-how-artificially...
That’s actually one reason I’m quite excited about wind and solar as a power source. Apart from the CO₂ that coal and gas pants emit (and the fugitive methane emissions from coal, oil and gas production), it seems like an improvement to be able to generate electricity without having to pump so much waste heat into the atmosphere with all that water vapour.
Earlier quoted context omitted.
It does still evaporate, it just condenses back to liquid shortly after. I don't understand the thermodynamics very well, but isn't the point of steam to carry heat _away_ from the plant? I'm wondering if the catch is that the plant would then have to deal with hot water removal instead of just venting straight up and out. Also, > What’s more, in many arid coastal areas power plants are cooled directly with seawater.…
Oh sure, there's cases where the output is more valuable than the input. I agree that desalination is possibly quite worthwhile. Though I'd imagine that in the ocean water case that the flow rate is high enough that little water is heated to the point of evaporating. Probably don't want to produce brine or salt residue. But much of the article talks about how 40% of lake, river, and well water goes into evaporative p…
Once it evaporates to steam, it mixes with more air, which cools it and the steam condenses to fog. But at this point, this heat transfer is of no consequence to the power plant. You can collect this fog without affecting the thermal efficiency of the plant.
But you can't skip that evaporation step because it's the high surface area of the sprayed droplets evaporating that does all the work. You also can't have the collector too close because then you just have a still, and the collector plate heats up from the condensation until it equilibrates. You need the air mixing.
Basically TFA describes a cheap way to get a much larger effective surface area.
Earlier quoted context omitted.
Oh sure, there's cases where the output is more valuable than the input. I agree that desalination is possibly quite worthwhile. Though I'd imagine that in the ocean water case that the flow rate is high enough that little water is heated to the point of evaporating. Probably don't want to produce brine or salt residue. But much of the article talks about how 40% of lake, river, and well water goes into evaporative p…
It's all about the surface area. The evaporative chiller couples the heat to a much larger volume of air, much more quickly, than a water-air convective heat exchanger. This is due to the high enthalpy of evaporation of water. The hyperbolic towers get an extra boost due to convection. Once it evaporates to steam, it mixes with more air, which cools it and the steam condenses to fog. But at this point, this heat tran…
If you find this interesting, there are other technologies either proposed or used to collect atmospheric water. Air wells: https://en.wikipedia.org/wiki/Air_well_%28condenser%29 Fog collection: https://en.wikipedia.org/wiki/Air_well_%28condenser%29
You've got an accidental double link to the same air condenser article -- here's fog collection for the lazy: https://en.wikipedia.org/wiki/Fog_collection