Passive cooling panels beam air conditioners' exhaust-heat into space


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Could the output be modulated to produce a beacon for our alien Space Brothers?


Global warming is so passé. Soon we’ll all be worried about Galactic warming.


does it come in a window unit?


I was just thinking that this would be another way to broadcast our presence and level technological development.


It all make sense except the magic material that creates microwaves by absorbing heat. I want somebody to 'splain that high level hocus-pocus part plz.


What do you think brought me here?


Seemed like a good idea at the time.


There has to be down side.


The basic principle isn’t new. It goes back to at least the Romans.


A flying saucer?


Add one more item to the list of awesome ideas that I never ever would have thought of.



A more detailed introduction to thermal radiation:


basically if you make oreos with silicon dioxide and hafnium oxide, you get a little piezoelectric thing. Squish it an it will generate a tiny current. Alternately, heat it up and it will put off energy (like the way tungsten does, as visible light, when you excite a formulation of it with just the right kind of electricity) but in the case of hafnium - just not visible wavelengths. Put that oreo over a layer of silver and you have a one way system, as the silver is a very efficient reflector.

This makes sense to me on a physical chemistry level, it seems plausible to me - and I am sure I have made rounding errors in my simple explanation, but there it is - wicked cool.

There is the cost to run the water pump, but the material itself is unpowered other than by absorbing heat. Neato.

also, MAGIC

What surprises me is that there isn’t anything in the atmosphere that would absorb radiation in that wavelength!


This seems like it would be a really big seller in space applications. It may not be elegant; but when you have an atmosphere(and often a nearby body of water) to work with, you can always press conduction into service; with some convection thrown in if you are feeling elegant.

In space, not so much. It’s just you trying to dump waste heat by radiation; with an inconvenient ~5,500 degree fusion sphere for company. That seems like the sort of situation where better radiators, even if the cost per unit area is painful, would have them beating down your door to offer you money.


You know me all too well.


Thanks for that!


That explains it!


That’s the side that against the ground.