Sciencemadness Discussion Board

Thermoelectric Cooling Mantle?

FireLion3 - 10-7-2014 at 10:02

I was thinking recently about endothermic and exothermic reactions. It's generally use to just turn the heat up to counteract cooling in an exothermic reaction.... but what about the other way around?

http://en.wikipedia.org/wiki/Thermoelectric_cooling

I looked into thermoelectric cooling a few months ago, basically the heat is rapidly transfered from one side of the element to the other and converted into electricity. A high level of effeciency could potentially be achieved if the set up were designed correctly. The idea of this would obviously not be to save the electricity, but it could serve as an awesome way to keep a reaction cooled precisely with a temp controller in play. With clever enough engineering, a person could incorporate both heating and cooling into one, and keep a reaction at a perfect temperature whether it is exothermic or endothermic.

These thermoelectric coolers can get pretty cold. I looked at one a while back that could get one side of the element down to -40 celcius in just a few seconds (with nothing on the element generating heat). Anyone ever thought about this? Would be a very neat engineering project, and a potentially profitable one. If these already exist, please point me to them!

WGTR - 10-7-2014 at 12:09

You might be confusing a thermoelectric generator with a thermoelectric cooler, but that's a common mistake.

https://tetech.com/product-category/cold-plate-coolers/

Of course, you don't have to buy the completed modules, if you have heat sinks laying around you can make them yourself. The coolers are fairly cheap by themselves. You just need some heat sink compound (like you would use when mounting a heat sink on a CPU), the cooler, the aluminum heat sinks, and the appropriate voltage/current.

Several years back I was performing a Kolbe electrolysis in a small 10mL beaker. Cooling was needed for best efficiency, so I mounted the hot side of a cooler to a heat sink, which was then submerged in a tub of water. The beaker was stuck to the cold side of the cooler with some heat sink compound. It got the beaker cold enough that it was sweating, and it worked well.

vmelkon - 18-7-2014 at 13:28

Quote: Originally posted by FireLion3  
I was thinking recently about endothermic and exothermic reactions. It's generally use to just turn the heat up to counteract cooling in an exothermic reaction.... but what about the other way around?


You mean an endothermic reaction.
Quote: Originally posted by FireLion3  

http://en.wikipedia.org/wiki/Thermoelectric_cooling

I looked into thermoelectric cooling a few months ago, basically the heat is rapidly transfered from one side of the element to the other and converted into electricity. A high level of effeciency could potentially be achieved if the set up were designed correctly. The idea of this would obviously not be to save the electricity, but it could serve as an awesome way to keep a reaction cooled precisely with a temp controller in play. With clever enough engineering, a person could incorporate both heating and cooling into one, and keep a reaction at a perfect temperature whether it is exothermic or endothermic.

These thermoelectric coolers can get pretty cold. I looked at one a while back that could get one side of the element down to -40 celcius in just a few seconds (with nothing on the element generating heat). Anyone ever thought about this? Would be a very neat engineering project, and a potentially profitable one. If these already exist, please point me to them!


Yes. I have bought a few. They are rated 90 W @ 15 V which means 6 A needs to go through.
Actually, if you run it in a cool environment, the resistance goes down and the Amperage goes up even more.

I was able to run it in my freezer (-26 C) and I did freeze mercury with it.
The second device I built wasn't able to freeze mercury.

You need 1 good power supply or a few if you are going to have a bunch of them. They take a lot of Amps!

Loptr - 18-7-2014 at 19:29

Are you talking about Peltier thermoelectric cooling chips? I think the coolers in vehicles use these and would be the equivalent of a "cooling mantle."