Hi Again

So a couple weeks ago was yard sale week in my neighborhood. Neighbor had one of those small wine cooler fridge things, but claimed it wasn’t working and thus she didn’t want to sell it. Said I could have it free if I wanted it. I took it, not really knowing how they work or if I could fix it. Opened up the back, and was originally confused, as I wasn’t sure what I was looking at, expected a small fridge type setup. Come to realize these things operate off of a small peltier cooler. Basically a small flat square. Apply voltage and one side gets cool and one side gets hot. Inversely, apply hot to one side and cold to the other, you get voltage/current. Now I knew these things existed, however I had never know them to be used to do actual real work, as they aren’t efficient and don’t scale up nicely.

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So I set out to fix the unit, got on ebay, and was happy to see you can get one for 3-4 bucks. http://www.ebay.com/itm/230961161033?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

So I ordered two so I have a backup. While waiting I did some research about them. Wikipedia had plenty of info. http://en.wikipedia.org/wiki/Thermoelectric_cooling  As I knew, they definitively are not efficient when compared to a compressor driven fridge, however, I do like that they are exceedingly simple. All you need to drive the unit is a voltage, up to 12V, and only 70 watts and a good heat sink on each side. Fans on each side help, but it would work without them. The amount of power can easily be gotten from solar panel, or other jerry rigged solution… Which got me wondering how this could potentially be used as a prepper item. I did go ahead and break open the broken (sorry forgot to take a pic), basicaly just a 3d grid of different materials. Now the thing is nice in that their are no moving parts and thus they have a very high mean time between failure of ~100,000 hours (11.4 years). As I stared at the thing I figured the thing should have a half decent chance of surviving and EMP (??). Not super sure, as of course I don’t have test data, but there really isn’t anything here to be damaged. Its essentially a wire made out of different materials… Even if, these things are small and low cost, so it would be easy to shield a few and even bury them if ya want.
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So now on to thinking about the circumstances where this would be useful. My mind instantly goes to an EMP, as in most other circumstances I think I would put my resources into a bigger fridge. I mean your really not going to be storing much of any food in this, and from a food resources standpoint, I would put my effort into longer term storage ideas, not requiring electricity. So what use could this little thing possibly have? Well, in the absence of real refrigeration, an actual cold glass of water can be ohh so pleasurable. Of course, depending on where you live there are likely other ways to get cold water. The one real use for a device of this nature, I find in the book One Second After. Imagine if you had a kid who needed insulin. Your utterly dependent on it, and it must be kept cool or it spoils. You would probably do anything to keep it cool, but if all electronics are fried, what are you going to do?

Which brings up the conversation of, how would you drive the thing after an EMP. We would all like to think at least we could get a solar panel and drive it, but it seems highly likely that the small electronic gates in a solar panel would fry.. The whole thing is like a big wire antenna… Also, solar panels are bigger and thus more of a hassle to try and protect from EMP. Maybe one could find a small DC motor and rig it to generate a minimal amount of current. There are a couple options, however, one thought I had would be to rig up a bunch of these in series and use several peltier coolers to drive one to do work… Essentially rig up, say 10 of them, on a long plate. On one side, run a pipe with water flowing through it (if you have a water source) or even just bury and tank of water and pipe that up. No you probably wouldn’t be able to pump the water, however it should still stay at a cooler temperature. So in theory your cold side gets as cold as the earth 3-4 feet down, then on the host side, a metal block (no cooling fins) and paint it black, then put up a greenhouse over it to trap heat, then add reflectors pointed inward, like a solar oven. Now I am not sure how much current this would really generate, but it would be a fun experiment. I figure if you get 10 of these trying to drive one, everything wired in series, you might just get enough power to drive that one, and keep some insulin cool. You could easily wire it such that the actual cooler is in a basement, while the 10 driving it are outside. 20-30 feet of wire at 12 Volts isn’t insignificant, but it won’t be a killer either. And if it is, just keep adding more cooling plates. If you built this ahead of time, then buried the contraption, it seems like a pretty darn EMP proof method of refrigeration, even if it is small.

I will leave with one piece of advice, don’t put alot of pressure on them when attaching the heat sinks, they crack easy enough. I learned the hard way, but I am stubborn and eventually did fix the unit.