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Earlier quoted context omitted.
I think you are thinking about an RTG instead of an actual reactor.
Some space craft have actually had full reactors on them believe it or not.
https://en.wikipedia.org/wiki/Nuclear_power_in_space#Fission...
What does the level of performance indicated here likely mean in terms of the efficiency of, say, a thermal energy plant of some description? How far is the needle shifted for an end user?
The Peltier and Seebeck effects are so grossly inefficient that even an order of magnitude increase in efficiency doesn’t bring it into reason for basically any purpose. I’m not actually aware of any device ever made that uses the seebeck effect in any substantial way other than the little heat powered fans people put on wood stoves. The peltier effect is just down right awesome, you put power in and now it’s cold!?…
Earlier quoted context omitted.
The Peltier and Seebeck effects are so grossly inefficient that even an order of magnitude increase in efficiency doesn’t bring it into reason for basically any purpose. I’m not actually aware of any device ever made that uses the seebeck effect in any substantial way other than the little heat powered fans people put on wood stoves. The peltier effect is just down right awesome, you put power in and now it’s cold!?…
My camp cooler is powered by a 60W peltier. Plugs in to any automotive cigarette lighter. It will keep things refrigerator cold for as long as you want, and it's almost completely silent in operation. There's tons of different models on the market. FWIW.
That's why you have to use a real fridge to do the work before starting the journey. And at that point, those electric fridges are only slightly more useful than a pile of ice packs.
Earlier quoted context omitted.
I think you are thinking about an RTG instead of an actual reactor.
Some space craft have actually had full reactors on them believe it or not.
However, thermoelectrics have an efficiency well below 10% (maybe a bit better with this improvement but not much). For that reason, future reactors in space will likely use Stirling engines instead.
Every time some phenomenon arises from a recipe of fairly typical materials I wonder what other surprises nature has in store for us. The idea that the crystalline structure plays a large role in the bulk thermal conductivity of the material is kind of mind-blowing at first and then retrospectively obvious.
Sadly the key here is lab scale and vanadium. Costs won’t make it worthwhile.
Easy, just build a fusion reactor capable of eventually producing vanadium from hydrogen, and you got yourself a stew going! Edit : Method of producing said reactor left as an exercise for the reader.
Earlier quoted context omitted.
If you have a very small cooling job, yes. Anything above a handful of thermal watts is still better off using a compressor.
We were talking just the other day about back-side power distribution in ICs. Basically you bury the power rails really deep, lap the chip down to half a micrometer, and add through vias to ge to the rails. So now you’ve got a very thin chip and all the power comes in on the side with pretty much nothing else on it. I wonder if you mount the chip backside up, put these little peltier devices on the hot spots, if you…
Earlier quoted context omitted.
My camp cooler is powered by a 60W peltier. Plugs in to any automotive cigarette lighter. It will keep things refrigerator cold for as long as you want, and it's almost completely silent in operation. There's tons of different models on the market. FWIW.
You realise how inefficient they are when you load it full of warm beer and run it for a few days and the beer isn't even cool yet. From that 60 watts of input power, you only get ~4 watts of cooling, and with some leaking through the walls of the box, the time to cool down something of substantial mass can be weeks. That's why you have to use a real fridge to do the work before starting the journey. And at that poin…