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Mechanical power generation using Earth's ambient radiation

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Re: Mechanical power generation using Earth's ambient radiation

#31

Post by adastra22 »

AstroNutt wrote: post #22
jasonpeacock wrote: post #5

Earlier quoted context omitted.

OTECs are amazing, and step 1 of "The Millennial Project: Colonizing the galaxy in eight easy steps"[0] [0]: https://en.wikipedia.org/wiki/The_Millennial_Project There's a shore-based research OTEC in Hawaii, but the best is a floating, closed-loop OTEC in the ocean.

Interesting link. I would think step 7 would come before step 6 though. I thought about this for a few minutes and can't come with a reason otherwise.

The timelines are increasing powers of 2. It’ll take much longer to colonize all asteroids than to settle Mars.

Re: Mechanical power generation using Earth's ambient radiation

#32

Post by monegator »

coder543 wrote: post #25
clickety_clack wrote: post #8

In one of the later Foundation series books, Isaac Asimov had a whole world run on this.

Which book? Which world? I don't remember this, but it has been a few years.

foundation and earth, if i recall correctly

Re: Mechanical power generation using Earth's ambient radiation

#33

Post by wombatpm »

cameldrv wrote: post #29

Not an engine, but some friends of mine got a mylar sheet that's black on one side and reflective on the other. We tried it out in the desert tied onto trees/vehicles. You put the shiny side down, so the hot IR radiation of the earth is reflected away, and the black side sees the extremely cold (in IR) desert sky. If you put a little hole in the middle and put a bucket under it, you get a fair bit of water, because t…

Now you just need a couple of droids and you could go into the moisture farming business

Re: Mechanical power generation using Earth's ambient radiation

#34

Post by viraj_shah »

cameldrv wrote: post #29

Not an engine, but some friends of mine got a mylar sheet that's black on one side and reflective on the other. We tried it out in the desert tied onto trees/vehicles. You put the shiny side down, so the hot IR radiation of the earth is reflected away, and the black side sees the extremely cold (in IR) desert sky. If you put a little hole in the middle and put a bucket under it, you get a fair bit of water, because t…

Fascinating 20 degrees C is huge. What's a fair bit of water? At what time of day and how long did you collect water?

Re: Mechanical power generation using Earth's ambient radiation

#35

Post by gsf_emergency_6 »

viraj_shah wrote: post #34
cameldrv wrote: post #29

Not an engine, but some friends of mine got a mylar sheet that's black on one side and reflective on the other. We tried it out in the desert tied onto trees/vehicles. You put the shiny side down, so the hot IR radiation of the earth is reflected away, and the black side sees the extremely cold (in IR) desert sky. If you put a little hole in the middle and put a bucket under it, you get a fair bit of water, because t…

Fascinating 20 degrees C is huge. What's a fair bit of water? At what time of day and how long did you collect water?

These guys claim >40degC, and are deploying in Dubai..

https://www.i2cool.com/tideflow/uwJVdixI.html

https://baitykool.com/radiativeskycooling.html

Peak performance, I think. Considering that they got the black white sides flipped

Re: Mechanical power generation using Earth's ambient radiation

#36

Post by jeffrallen »

wombatpm wrote: post #33
cameldrv wrote: post #29

Not an engine, but some friends of mine got a mylar sheet that's black on one side and reflective on the other. We tried it out in the desert tied onto trees/vehicles. You put the shiny side down, so the hot IR radiation of the earth is reflected away, and the black side sees the extremely cold (in IR) desert sky. If you put a little hole in the middle and put a bucket under it, you get a fair bit of water, because t…

Now you just need a couple of droids and you could go into the moisture farming business

Nah, those are not the droids he's looking for.

Re: Mechanical power generation using Earth's ambient radiation

#38

Post by yetihehe »

ufocia wrote: post #13
AnimalMuppet wrote: post #9

Earlier quoted context omitted.

Mechanical things don't usually work for 100 years with no maintenance. Bearings run dry, if nothing else.

Air bearings always run dry without problems.

Air bearings run dry until they get some moisture. Then they fail. Old joke about making radio enclosures: make it as watertight as possible, then drill a small hole on the bottom to let the water escape.

Re: Mechanical power generation using Earth's ambient radiation

#39

Post by kragen »

cameldrv wrote: post #29

Not an engine, but some friends of mine got a mylar sheet that's black on one side and reflective on the other. We tried it out in the desert tied onto trees/vehicles. You put the shiny side down, so the hot IR radiation of the earth is reflected away, and the black side sees the extremely cold (in IR) desert sky. If you put a little hole in the middle and put a bucket under it, you get a fair bit of water, because t…

Wow, that's awesome, and a much bigger temperature difference than I would have guessed. Did you get frost?

Re: Mechanical power generation using Earth's ambient radiation

#40

Post by kragen »

jcims wrote: post #14

DIY radiative cooling paint from YouTuber NightHawkInLight - https://www.youtube.com/watch?v=N3bJnKmeNJY&list=PL1a2HkcVbm... It has pretty impressive performance. Tech Ingredients did one or two vids as well - https://www.youtube.com/watch?v=dNs_kNilSjk Was thinking of whipping up a batch for my rv.

IIRC, the papers they're working from mention that lime works very nearly as well as the baryta they're using. Guess what people have been painting their houses white with for several thousand years?
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