Solid-state micro-fridges; Don't bother.
8One class of item I’ve never seen here on Meh is the solid-state micro-fridge. You’ve probably seen them advertised often enough, and they can seem like a really great idea. “No moving parts” except the fan that they can’t work without. (And if they leave out that fan…just no.)
Anyway, here’s a video which does a stunning job of explaining just why those things are close to worthless, and incidentally provides a lot of clues why the large battery/inverter packs like the 991Wh Eveready power station plus a regular fridge can actually work as a viable way to keep your food safe for hours during a power failure.
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Agree not great at all! Originally had a big one (cooler-chest size) used in a motorhome in the 1990s. In 90-degree weather will keep things at about 70 degrees. In 40 degree weather will freeze the S$%# out of whatever is in it. The technology was developed in the space program in the 1960s and serves a useful purpose but not great for small refrigeration/freezing needs. (called Peltier effect if I recall). Also these are not efficient in terms of power use compared to how effective the cooling is. One “plus” if you can call it that is if you reverse the power, it can “heat” things, but again it’s only 20-40 degrees above where you are so it’s not going to “cook” food but might keep it warm.
At that time when I used that thermo cooler, 1990s, there were compact freezer chests with compressor technology (still the only good way to cool effectively), but they cost $600-$1000 and up. Now there are lots of low-cost compressor technology systems available from around $200. Note that the cooling system does add quite a bit of weight and takes up space, so people often complain about not having enough space inside the cooler because a chunk of it is taken up by the cooling system.
Depending on your needs I have to say getting a super-good quality heavily-insulated cooler chest (without refrigeration) is an alternative if you are only looking for a few days of cooling. This is like the Yeti or Otter brands which will not be cheap (some will be as much as a new import no-name compressor cooler). But if you are doing something like a 4WD trip or hunting or fishing for a few days, might be better.
@pmarin Peltier actually discovered the effect in 1834, but the electronic hardware to make it a “practical” method didn’t exist until the '60s. And as noted in the video, it is far less efficient than the usual compressor-refrigerant systems.
@werehatrack It’s absolutely a “cool” thing (or warm, depending on DC polarity). I believe it was essential for things in the Apollo generation and would not be surprised if it is still used many places on the ISS. Not sure what Tesla/SpaceX uses but would not be surprised if used there too. Was interesting to watch that brief depressurization/space-kind-of-walk a few weeks ago. If you see interviews when crew was safely back on Earth, they mentioned that even in the suits with cabin mostly depressurized, once exposed to space they could feel the overwhelming emptiness and the cold. (Unlike classic EVA suits don’t think they had heating/cooling in the suits). So somehow once they were all safely inside and pressurized again, there must have been some way for the cabin to heat pretty quickly. Doesn’t seem that Peltier alone would do that quickly enough. Might just be old-fashioned resistive heat. Uses lots of power but if you’ve got enough it’s OK.
Another crazy idea is like the mini-icemakers that now go on sale for <$100. They don’t make a lot of ice at once but can keep running (just need to take out the ice and keep adding water). They run on 120V but could use an inverter or AC inverter powerbank. But kind-of a pain to make enough ice to keep something big cool. But yeah ice is ice and put it in a plastic bag in a cooler and it will cool things.
I was “working-around” my failed RV refrigerator last year using a compressor-cooler chest, plus tried the icemaker. Decided the icemaker was fun but a bit too much work (would run it at night when in RV parks with power).
I need to replace the refrig in the camper. Too big/heavy for me to try swapping it myself. New ones now use 12V compressor technology – old ones used propane and/or 120V power for an “ammonia cycle” system which tends to fail and was not efficient. Though it still seems crazy that making a flame with propane would result in a refrigerator/freezer that basically worked, and the technology for that is like 100 years old.
One of my favourite YouTube channels along with Aging Wheels.
@yakkoTDI I’m surprised he hasn’t obtained a Zap! yet.
/image Zap Xebra
Granted, most were recalled due to failing to meet braking standards.
ETA: their final fate:
@narfcake @yakkoTDI Hah! It looks like an aphid.
@Kyeh @narfcake Give him time. Now that one of his Solos has been crashed him has room for a Zap Xebra.
If this wasn’t the posted video, I was going to post it. Found that guy’s channel a little while back (thanks, algorithm) and love him to death.
Okay so I saw his video on my feed yesterday (I subscribe) and I knew this thread was gonna be a link to it the second I saw it. Full disclosure, I have yet to watch the video, and I’m sure he makes some great points, but hear me out…what are you supposed to replace these things with for their intended purpose? They are, AFAIK, the only practical way to keep things cool for long periods (greater than a few days) without AC power and/or in small spaces. I have a few of these, the best one being a Koolatron, and I’ve never had issues with stuff like soda cans and other non-perishables. They keep it just as cool as my big fridge does, so I don’t understand why someone would outright say NOT to buy them. They do, in fact, work. Thermoelectric/Peltier cooling/heating is a thing that works, isn’t fake in any way, and doesn’t presently have an alternative within the same parameters and/or use cases.
@PooltoyWolf Watch the video and become even more acquainted with the devices - and their drawbacks.
@werehatrack What is the viable alternative?
@werehatrack Having now sat down and watched the video in full (entertaining as Alec always is) he made some good points, though these devices are still the best way to perform the task most of them are built for: part-time cooling in small spaces for cheap. There simply isn’t another way to cool stuff in a car or other small space for short time periods, at any price. But yeah, if you’re looking for something to run continuously (dorm room or under cubicle desk, etc.) definitely spring for the costlier, but roomier and more efficient minifridge. (As an aside, I found the energy consumption comparisons to full size refrigerators to be disingenuous, since their use cases for the vast majority do not overlap.)
@PooltoyWolf @werehatrack The only place I’ve seen these in the wild is in a car, which is (apparently) the prime example of where they’re a valid (or even “good”) option.
I found one at a yard sale many years ago and tried it on a couple trips. I was not impressed. Possibly the one I had was defective or broken… but for the most part it just didn’t seem as effective as a cooler (for how I was using it). However it could have been better than a cooler if my needs had been different.
¯\_(ツ)_/¯
@PooltoyWolf @werehatrack @xobzoo From his pinned comment on the video.
@werehatrack @xobzoo @yakkoTDI Oh I read the comments, don’t worry!
Ok so what is the “better” alternative? This
https://www.monoprice.com/product?p_id=44268
I have one; it works well. Real freezer technology will cool to whatever you set digitally, 34-40 for cooler, or down to -4°F for frozen. Regardless of how hot ambient is. As I mentioned downside is a chunk of space is taken by the refrigeration system, and adds a couple of pounds of weight. On long trips I just keep it (along with toolboxes and stuff) on folded-down backseat of my truck. In cold weather I don’t even need to keep it running all the time, but can plug in to AC if I am at an RV park or to vehicle 12V.
@pmarin Vs a Peltier junction cooler, yes the monoprice compressor is a better choice. BTW, If by ambient you mean the outside air temperature. Then no, the compressor coolr will not work regardless of how hot the ambient is. After 100C functionality drops off steadily and around 115C or so you won’t have any cooling. You have to have a cooler ambient than the compressed refrigerant in order to dissipate the heat. Heat always goes from a hotter body to a colder body until equilibrium is reached.