Woah, this seems really simple and possibly applicable to other situations where you're trying to condense a vapor.
Will it be something like the ones used for binary load lifters?
I know many of the big data centers use a ton of water in areas that don’t exactly have water to spare.
Air wells: https://en.wikipedia.org/wiki/Air_well_%28condenser%29
Fog collection: https://en.wikipedia.org/wiki/Air_well_%28condenser%29
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.
Also,
> What’s more, in many arid coastal areas power plants are cooled directly with seawater. This system would essentially add a water desalination capability to the plant, at a fraction of the cost of building a new standalone desalination plant, and at an even smaller fraction of its operating costs since the heat would essentially be provided for free.
This seems like a no-brainer and it's surprising to me that it doesn't already work this way.
But much of the article talks about how 40% of lake, river, and well water goes into evaporative power plant cooling. Recovering that already-salt-free water via condensation vs just not evaporating it in the first place seems silly. Your car doesn't use evaporative cooling, it uses a heat exchanger. So too could a power plant.
Though if the working fluid is steam I guess we'd call it a condenser rather than a radiator. That said, if you have steam to exhaust you have energy left to extract. My home water heater condenses the steam out of combustion exhaust to achieve good efficiency.
The point of steam is to turn a generator, these plants are basically steam engines using heat to produce steam for driving a turbine.
Edit: I think I'm wrong in that the steam loop for driving the turbines is isolated from the loop including the cooling towers which is strictly for cooling the closed generation circuit via heat exchangers to condense the steam... you're right.
To do the same with a heat exchanger would need a much much bigger heat exchanger, and some of these evaporation systems are already pretty big.
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.