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Engineers harvest clean, continuous energy from air

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Re: Engineers harvest clean, continuous energy from air

#21
post #17

Earlier quoted context omitted.

I don't really see anything harvesting the wind aside from us?

Plants do it all the time; the basic plant strategies for colonizing new territory are floating on the wind, floating on the water, and fruit.

I guess spiders use it for getting around as well, and birds use it as well. I guess I was more thinking like photosynthesis.

Re: Engineers harvest clean, continuous energy from air

#22

Despite being a chemist, I don’t fully follow this, though it seems legitimate. But if there’s that much latent energy, I really have to think that there could be some kind of atmospheric, “local ecological” side effect on microorganisms or “something” at scale. It’s not like nature lets massive amounts of energy go completely unused.

Completely? No. But consider how much of a given square meter of sunlight on the ocean is photosynthesized by bacteria and algae, and how much becomes waste heat immediately.

That's not "waste" heat as far as the ecosystem is concerned. It creates the ocean thermocline which drives ocean currents and nutrient exchange between layers. Without it everything in the ocean would starve from lack of basic minerals or suffocate due to lack of dissolved oxygen except around river deltas.

Re: Engineers harvest clean, continuous energy from air

#23

Something similar happened when I put a dehumidifier in my bedroom. Basically, I noticed that the room was heating significantly when I turned it on. Way faster than what you should expect from its power usage (about 250W avg.). Correct me if I'm wrong, but by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor (0.627Wh/L) in addition to its own e…

Dehumidifiers are heat pumps. The heat source is latent energy in water vapour.

Re: Engineers harvest clean, continuous energy from air

#24

Something similar happened when I put a dehumidifier in my bedroom. Basically, I noticed that the room was heating significantly when I turned it on. Way faster than what you should expect from its power usage (about 250W avg.). Correct me if I'm wrong, but by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor (0.627Wh/L) in addition to its own e…

Given that a dehumidifier is doing the opposite of a swamp (evaporative) cooler, this makes sense.

Re: Engineers harvest clean, continuous energy from air

#25

Something similar happened when I put a dehumidifier in my bedroom. Basically, I noticed that the room was heating significantly when I turned it on. Way faster than what you should expect from its power usage (about 250W avg.). Correct me if I'm wrong, but by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor (0.627Wh/L) in addition to its own e…

doesn't humid air "feel" warmer, though?

Re: Engineers harvest clean, continuous energy from air

#26

Something similar happened when I put a dehumidifier in my bedroom. Basically, I noticed that the room was heating significantly when I turned it on. Way faster than what you should expect from its power usage (about 250W avg.). Correct me if I'm wrong, but by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor (0.627Wh/L) in addition to its own e…

That's interesting, will test this right away myself!

Re: Engineers harvest clean, continuous energy from air

#27
post #20
post #4

Earlier quoted context omitted.

> more than a kilowatt (per hour?) Not sure what you mean, Watt already has a unit of time in it.

The paper just says "an estimated energy density of >1 kW/m^2"

That's quite an amount, about 3-5x the amount of energy generated by solar cells of the same surface area. It would mean the device would generate $2000-$4000 on a yearly basis.

Re: Engineers harvest clean, continuous energy from air

#28

Something similar happened when I put a dehumidifier in my bedroom. Basically, I noticed that the room was heating significantly when I turned it on. Way faster than what you should expect from its power usage (about 250W avg.). Correct me if I'm wrong, but by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor (0.627Wh/L) in addition to its own e…

doesn't humid air "feel" warmer, though?

Warmer if it's warm, colder if it's cold. I think the deal is that it's more efficient at transferring heat to/from your skin.

Re: Engineers harvest clean, continuous energy from air

#29

Something similar happened when I put a dehumidifier in my bedroom. Basically, I noticed that the room was heating significantly when I turned it on. Way faster than what you should expect from its power usage (about 250W avg.). Correct me if I'm wrong, but by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor (0.627Wh/L) in addition to its own e…

> by converting air moisture to liquid water using a compressor, the dehumidifier is releasing the latent energy of water vapor

The latent heat does get released, but the question is, where does it go?

In an air conditioner, which also condenses water vapor from the air, the heat released goes into the refrigerant, which means it ultimately gets put into the atmosphere outside from the condenser.

A dehumidifier is basically an air conditioner without an outside unit, so the heat from the condensation of water vapor goes into the refrigerant, but then gets put into the room from the condenser, instead of outside.

Re: Engineers harvest clean, continuous energy from air

#30
post #20
post #4

Earlier quoted context omitted.

> more than a kilowatt (per hour?) Not sure what you mean, Watt already has a unit of time in it.

The paper just says "an estimated energy density of >1 kW/m^2"

Didn’t it say cubic meter, not square?
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