I did some quick back-of-the-napkin math, and for a can of coke, to cool it from 17 to 8 degrees requires 14 kJ of energy. If the peltier device was 100% efficient (which it very much isn't) it would take 3 minutes and a bit to cool the water. The peltier element is much more likely to be around 20% efficiency or less, therefore it would take around 15-20 minutes to cool the can of coke. The issue is really that water has a very high specific heat capacity of 4.2 Joules per gram Kelvin, meaning it takes 4 joules (or 4 watts for 1 second) to cool 1 gram of water 1 degree. Helpfully, a gram of water and a milliliter are pretty much the same. Or in other words, to cool the can of coke in 2 minutes with a 20% efficient peltier element would require nearly 600W power draw.
Now this is my favourite kind of napkin maths! Thank you so much for describing this - this is unbelievable useful. At least now we can understand a ballpark upper range of how long it might take under an ideal setup. So really, even with a couple of 300 watt power supplies, and a number of Peltier modules with optimal cooling, we're still looking at a period of time longer than just chucking it in the freezer for 10 mins. I'm glad I didn't continue eking out minor improvements in efficiency! Really appreciate your help here ❤️
Considering he was running those poor cells as hard as he could, and that he didn't provide any insulation, 20% seems a fairly optimistic estimate... I would have guessed 5%, or even less
@@Beregorn88 I'm not an expert on peltier elements so I just looked up typical efficiencies, and 20% seemed to be in the middle of what people were saying, so I went with that.
@@JamiesBrickJams Cool project! I never considered a lego fan ;) Several more forms of thermal loss: Thermal pads are convenient and clean, but nowhere near as good at heat transfer (especially to the ceramic of a peltier module) as thermal grease. You could likely drop the hot side's internal temp substantially with better TIM (Thermal interface material) which would increase your efficiency by an order of magnitude. Even junk thermal grease is typically on par or better than gap pads. Your metal cup is acting as a heat-sink heating the water using the air. It might be that those water blocks just aren't great at transferring heat. Thus, the cold side may be getting far colder than the water. Peltiers are most efficient when the temp difference is minimal so stacking two water blocks on one peltier then a single block on a second peltier may net you some more performance. (so, pump -> top block 1 -> bottom block 1 -> block 2 -> cup. Here where both "block 1"s are on one TEC and block 2's are on a second. Peltiers can actually be quite efficient, but typically at low power at small temp differentials. I have achieved 38%+ with a good test setup and name brand modules. Also, using cheap modules I have gotten to -30+ degrees F. You can use detect radiation and cosmic rays by building a "cloud chamber" with this method.
@@nathanielhuggins9254 True, those thermal pads are pretty useless. Also, could be wrong, but I think they depend on getting hot, at first, to mould themselves around the CPU surface they're usually supposed to be cooling. If you're dealing just with flat surfaces, much better to use thermal paste as you mention. And maybe spring pressure or some elaborate Lego mechanism to keep them firmly pressed onto the heat sink. CPUs use the sort of springs you could do the suspension on a monster truck with, they have power!
honestly for the inefficiency of a peltier device, you're more than likely better off just pouring the water in a shallow bowl in front of a regular fan and letting evaporative cooling do the work instead
for the peltier system, you'd have to wait until the water cooling block is about as cold as the peltier. although if you had an exchanger, you could have a closed cooling loop that's continuously cooling only a small volume of water then transfering the cooling to your drink.
That's what I figured, I did try to wait about 5 minutes to drop the temp, but it seems like the block just refused to get low into the minus figures. I've a suspicion that the block actually heats up the cold side too much, causing it to run way less efficiently. It seems to drop the temp difference it's able to create. But in general I'm sure you're right that a slower trickle passed through it should work better! Or perhaps multiple trips through the system
@@JamiesBrickJams I have read the comment with the calculations. But my idea for improvements would be a bigger peltier and cooling block, and 2 of those peltiers so you can sandwich the cooling block between them. Still, for proper cooling you need lots of power. Same as with heating. I gues you should look into constructing of a Lego heat pump 😅
1:16 - Peltiers get more efficient at lower power so getting a bunch of them and running them at 50% power would be more efficient than running the equivilent single one at the same power, it also helps to move the heat away from the peltier rather than dirtectly cooling it but that gets more expensive. 2:46 - looks like you are already working towards that, 👍
Ah that's really interesting, thanks for your comment! I do have a lot of these modules, so perhaps running 6 of them at half power might work? Might have to invest in a few of those larger water blocks and attach multiple units to it
@@JamiesBrickJams And a few other things, you don't need that beefy water blocks nor your silicon pads. Both of them increasing temperature mass and the time, in the end. Also, if you want to squeeze as much COP as you technically can - you should isolate all your cold side from the ambient, and definitely start to use double-sided glass, cuz you should keep the already cooled liquid as far as you can from ambient temperatures. And definitely, pouring more energy into peltier modules isn't a great idea too, because from their poor efficiency, let's say 20%, remaining 80% are gonna be heat, so more power you're make them chug - more heat they gonna release, and heat losses doesn't give a flying fk where's your cold side. Because of that, peltier modules is really useful only in car can chillers, because they're too weak to actually cool them, but their power output is viable to keep them at the same temperature (and with insulation of the box as well...)
You are dealing with enthalpy. Water holds a huge amount of btu’s. You are trying to move btu’s from the cold side of the peltier chip to the other. The chip surface may be cold, but it’s ability to move btu’s across to the hot side is almost as inefficient as its electrical use.
I'm pretty sure you're absolutely correct here, and thanks for confirming what I was suspecting. These things are so inefficient and I'm amazed to see how many silly videos seem to suggest you can make reasonable air conditioners and other ridiculous claims using these. And water seems to be particularly challenging to draw heat from too. Thanks for your comment here 👌
Using silicone as a thermal pad will have definitely impacted the performance of this device. Silicone is not a good conductor of heat and is actually more of an insulator. Theres a reason why silicone oven mits are so common nowadays.
I think you could make it work better by creating a loop and cycling your whole drink through it multiple times. Maybe also using thermal paste on the peltier will give you better transfer
I had a similar idea to the last. run the tap water through a air/liquid heat exchanger before using the water. so during summer, you can have cold air blowing on you while you wash your hands with cool water. or during winter pre-warm the water before it hits your hands.
i have used and played a lot with Peltier modules, the main problem i see is the silicon pads, even those thin ones you use are less thermally conductive than direct contact without thermal paste the way i usually stick them on a heat sink without a way to clamp them is a dab of superglue on each side/corner, and i recommend using a tiny bit of thermal paste (with the next to non existent pressure the glue applies, you really don't want a lot), while the glue is drying make sure to apply a LOT of pressure so it can have as much pressure as possible when dry to help thermal transfer also, if you use those water cooling blocks, you might as well use some clamps on them to increase pressure (and use thermal paste, I'm serious when i said those pads are really poor thermal conductors) also, if you run them at a lower power (which makes them a LOOOT more efficient), you can stack them to have much colder temperatures (but like 4-10 times less cooling power(it's like top speed versus acceleration in a car, but your transmission is made of paper, if you stack to many Peltiers and put too much current through them the lower ones can't sink the heat fast enough and all you get is thermal runaway as they get hotter, more resistive, make more heat, and yeah you get the picture))
you could have it cool a larger reservoir of anti freeze, and run that through a closed system. Then run the chilled coolant through a liquid to liquid heat exchanger that you put into the drink.
I've gotten something like this to work. I used a skived copper heat sink. The thermoconductivity of copper is nearly 400 W/m-k while aluminum is nearly 240 W/m-k, meaning the copper will take away a lot more heat. Copper heatsinks are a lot heavier and costlier but they work really well given the space.
You should try joining the heatsinks and peltier blocks with thermal paste. This will let the heat flow better and allow the heatsinks to have equal amount of cooling. Also thermal paste is better that the squares because it is like a thick liquid and fill cracks and spaces better. I got 7c water with a large heatsink and fan with a small peltier at 50w.
It would help a lot if you infinitely circulated your drink through the blocks rather than just one pass. That way it would get cooled a lot more because of multiple passes through the cooler
Someone else doing something similar did the exact same thing you did at the end but had the same coolant recycled repeatedly and cooled it down in a tank rather than the sink which would probably provide a helpful buffer.
Honestly for better thermal transfer I would onto both the cooling surface and the radiator surface use small pads as I saw you didn't for the transfer to the water block. Keep in mind more surface area for thermal transfer to a liquid would be best as well to have some fins in there. Also furthering that the transfer speed of the pump may be warming it back up as well. IDK if this helps much but love the vid!
The water cooling at the end seemed to have worked well. You should be able to cool water with a big surface and some airflow, like a baking sheet full of water and a fan. Lego is best for structures but limited in energy density. So you might take advantage of a larger surface area.
Insulating the hot from the cold side should help and maybe using "better" thermal pads most standard thermal pads are pretty crap for going bellow zero they lose their elasticity and stop cunducting the residual heat as efficient, the hot side should be ok with thermal pads. I would use thermal paste for the cold side. Also using two seperated cooling blocks might reduce the efficiency even more i would opt for a single double wide one.
Used to have a single-can sized "fridge" that was just a fan, heatsink and peltier device powered by USB 2. Since I have 0 use for it I just disassembled it for parts. Nowadays you can buy cooling bags for cans and bottles, probably even better.
That's cool, I wondered if those little fridges were just Peltier modules in them. And you're probably right, I'd imagine a cooling bag is much more effective. Certainly quicker
The Peltiers don't produce a massive cooling effect. Insulation is the key! Cut polystyrene appropriately to insulate out heat wherever you can. Also looks like the pop isn't spending enough time in the cooler blocks, perhaps recirculate it around a couple of times? Or else slow down the pump, but I suspect with a peristaltic pump, slowing it down would just stop it working as there's a certain amount of back-flow. Maybe have the pop recirculate round and round, back into it's jar, then after a few minutes activate a second pump that actually serves it into your cup. Or pour it. And the cup, too, could do with being in a big block of expanded polystyrene. Polystyrene everywhere! Or some sort of insulation at least. Think how long it takes one of those Peltier mini-fridges ( _with_ insulation) to cool a can. It'll be half an hour or so. Hence you need to recirculate the pop, a couple of minutes to do a whole cupful isn't long enough.
@@JamiesBrickJams Thank you for responding, I'm not usually noticed by RUclipsrs like you, your the third RUclipsr that responded. Thank you sooooo much!! Also could you try to make a hose to water plants? Thanks again!
@@JamiesBrickJams Bruh I literally nine and I'm already soooo interested in stuff like this, thank you for coming to RUclips and sharing your inventions!
Thermal pads are pretty bad at transferring heat, you should really avoid using them. Even a bad thermal paste is orders of magnitudes better. Use a good thermal paste instead and keep the mounting pressure high, this should dramatically help. This goes for both sides of the peltier, your bottleneck is most likely how fast you can get heat away from the peltier. The hotter the peltier gets the less efficient it becomes, creating a cycle that heats more and more. Thermal paste
aside from the bottleneck of the peltiers, it'd probably be more efficient if you were able to isolate the hot and cold sides so the temperature isn't able to return to equilibrium, say as a liquid in a closed loop, it'd also help if the cold side was enclosed so the ambient temperature wasn't constantly warming the water back up, say, an insulated box with a handle for easy acce- I'm describing a mini fridge 😅. jokes aside, I'd love to see a lego powered heat pump fridge.
8:44 thermal pads arent great at heat transfer, thats why we dont use them on computer processors (we use them on memory and other components though because the components tend to be oddly shaped and don't output much heat). Additionally the heatsinks are squished down via mounting pressure which is incredibly important for thermal pads and pastes to work well. I'm curious if your abomination would perform significantly better if you had used a thermal paste like Arctic MX-6, or even a graphene sheet (Thermal Grizzly makes some). Alternately there's also PTM7950 which goes on like a pad but then melts under load -- but thats meant for a permanent installation: costs more, performs better, and doesnt need replacing, but a bit of a waste on a project like this. That said, someone else calculated the cooling efficiency of cooling the water/drink and yes, water is quite difficult to heat or cool (majority of energy during cooking is literally just heating water) Like it's so high that we opt to move it mechanically when it freezes in winter (that is: we shovel it) because its less energy intense than attempting to melt it. Its thermal capacity and conductivity is amongst the best materials we know of (amongst other attributes, water is truly a chemical miracle), it would take an insane amount of time and power to equal just running cold water over the can like you did at the end :)
use thermal paste instead of thermal pads, they are much better at transporting heat. Also apply pressure from the Heatsink to the Peltier to improve the performance of the pad
@@JamiesBrickJams and as i now looking at the device i would also recommend to use something like a CPU cooler(like that one in the beginning of the video) because they have heat pipes wich spread the heat more efficiently,so the whole surface area is used for cooling and not just a small point. For your application i think you could scavange the heat sink from a old GPU like the gtx670 because they are really flat and have a large surface area so it will fit in your current design without major changes
@@JamiesBrickJams another idea is to go for water cooling but for that you will need a radiator wich further complicates the device. I think just dumping the hot water in a large bowl filled with water could also work since you are only running the peltier at 17w
That'd be quicker than the Peltier device for sure! But I tested putting a can in still water (and not moving the can), and it takes a fair bit longer. Also when the water is sitting in something for a while, the water heats up rapidly, so the drink can't get as cold. I'd imagine your best alternative is just chucking your drink bottle into a bucket of ice or ice water. But I enjoy overengineering things 😁
@@JamiesBrickJams The movement of the water/can surface is key. The can in a still bucket will essentially warm up the water right around it and that severely affects how fast it can cool. When you spin the can and water super fast then you are using the "cold" of the entire bucket of water at the same time
Try looping the water through the system multiple times therefore it will pass through it more and cool down more and then have an output where you can release it when you want and not immediately because it will take some time to cool down a fridge does the same thing where it loops it several times
@@JamiesBrickJams It basically uses ice and cold water in an enclosed space, kind of moving it around while rapidly spinning the can and that absolutely blitzes the can down to a couple degrees within a minute or so I think.
If your fan blows air through the channels of the heatsink, instead of just blowing it onto the top of the fins (against gravity aswell), you'll have more efficient use of the heatsink. A low-tech proposal for cooling the drink, along the lines of other comments: put your can into a small container, preferably made of aluminium or copper (the thermal conductivity of copper is roughly twice that of aluminium) with 3-4 mm of water surrounding the can. The container should have an upper section with fins, i.e. a heatsink section, where the bottom part of the fins are submerged in the water. Now blow on the fins with a fan. This way, you are assisting evaporative cooling by forced convection and aiding the natural convection in the water by the high thermal conductivity of the (aluminium/copper) container. Hope that makes sense, good luck and thanks for some very entertaining and high quality videos!
I would have figured out a way to use thermal paste as those thick pads are holding it back. Still cool though. You could even use tooth paste! Find a way to clamp the waterblocks down as that will help a bit.
Let the water block cool down so all of the heat gets pulled from the water block rather than the water. Less thermal mass to cool down at the same time
I had a project about Thermoelectric Coolers, it was hard to generate cold water but i suggest to do the opposite. I noticed TEC's are better if you generate heat using ice that the practical use are making hot or warm choco/coffee that will be use to places with snow. The device can be a portable drink heater... I think in this way, it will be more efficient.
You should look into how PC liquid cooling mechanisms work, it might help provide a bit of info. I do suspect conductivity to be the issue at hand though I don't know how exactly to fix it.
Hey man, I saw this and the following rang my bell through the whole video. You have the hot side of the peltier facing downwards. If i were you I would repeat the measurements but turning upside down the peltier-group, also making sure the heatsink fins are facing up and trying to direct the air pushed by the fan through a duct from the side through all the fins of the heatsink. Surely most of the heat transfer is thermal conduction (and the orientation of the heatsink in space shouldn't affect this), but doing this may help somewhat in the convection part of the heat transfer. It may not sound so appealing because you need to work the other part of the design out I suppose. I hope this helps you!
i feel like its not about the contraption, its about the Water thermal capacity. i think its one of the substance with the highest. you need to add lot of energie over a long period of time to make a change. and its reversible
you could fix it by add maybe a pack of ice optionally on top of the fan to cool down the air and also 3d print some those thing use in car intakes to direct the airflow only up
maybe use Good Thermal Paste like the Artic MX-4 and find a way to press the heatsink and cooling block on the white element. This would make it better. Run them on parallel and it would be a lot better. Maybe use some insulation too
It will be more efficient if you used high thermal conductivity thermal paste made for computers. Also, using the CPU cooler you showed earlier in the video would be much better than that aluminum heatsink at it has a higher fin density.
Get some water. Put it in a mold of your liking. Then put the mold with the water in a freezer. In a couple of hours, check the molds. The water should have turned solid. If not give it some time. When the water turns solid get it out of the molds. Put the now solid cold water in a cup and pour your drink in the cup. Bam! Cold beverage.
The biggest issue is that you're passing water over the cooler way too fast. I'm surprised the tap worked that well.. but actually.. it kinda makes sense from the surface area to volume ratio and timing.
Cool the hot side with water cuz more heat goes to the cool side and wait until the water blocks get cool. Additionally you could use stronger peltier modules
Ooooh I like that idea! So water cooling the hot side? Damn I should have tried using those water blocks on the opposite site too. Great idea, I'll give that a try for sure
Steel Ice in a tumbler , pour the drink in lock in with second tumbler (like a bartender before they shake your martini) tip back and forth between the two tumblers about 4-6 times , pour in fresh glass. Use legos to tip the tumblers like a teeter totter
For a start: Peltiers are really disappointing. 1:30 - You have put a metal jug in front of a fan... the fan is heating your liquid. Are you sure that silicon pads are thermal efficient? Try thermal paste and a better fixation of the peltier to heatsink and block. Make a thermal isolation on your block. Make the pump run slower, the slower the colder as you give time to peltier remove the heat. Check if your fan is moving enough air, the colder the peltier hot side the colder will be the cold side.
One thought is that you have the hot side of the peltier device on the bottom, and we all know that heat rises, so the heat from the hot side of the peltier device, along with the heat from the heat sinks, is heating up the cold side of the peltier device, thus negating the temperature difference. Try building it so the cold side of the peltier is at the bottom and the hot side is at the top so the thermal difference is assisted/maintained by the laws of thermodynamics.
Hmmmm that might not be a bad idea, cheers for the idea. I see no reason why I couldn't run the cooling beneath the module and extract heat from above. As someone else noted, it might even be worth using water to cool the hot side!
@@JamiesBrickJams oh and water in Ireland isn't free, to quote Uisce Éireann, aka Irish Water, "it's a precious resource that we're all responsible for". Although, given the number of mains repair work jobs logged on their website, Irish Water is pissing it into the ground due to a complete lack of maintenance over the years, especially the years before the Irish government's failed attempted to privatise the national water supply, using their Garda thugs, in an attempt to introduce yet another stealth tax on its citizens. ✊🇮🇪✊ 🇮🇪✊ 🇮🇪
True, and that's one of the main reasons I don't want to waste water. Having lived in South Africa where it is a scarce resource, I really don't like the idea of being frivolous with it. But not having a number appear on a bill makes it feel sort of 'free' 😅
@@JamiesBrickJams Not to bitch too much, but the Irish Government is like do as we say, not as we do. You have that pillock Eamon Ryan telling all us plebs to walk, cycle, use public transport, or get small electric cars, while he drives around, alone, in a VW transporter. The level of hypocrisy just keeps getting higher and higher, like 100/10 high FFS
Obviously Peltier heaters aren't at all efficient. But what we are really dealing with here is a specific heat problem. Water (and water-based beverages) is *very* resistant to temperature changes, whereas air and aluminum are not. Because we are trying to cool water essentially by transferring the heat to aluminum and air, you would need a much larger quantity of air and aluminum cooling to match the amount of heat in the water. Even without losses of efficiency in the cooler itself, the mass of air and aluminum required is ridiculous. The other option is water cooling your water, which is exactly as ridiculous as it sounds.
That's a good idea - I actually did try different speeds, allowing 10 minutes to slowly pump the fluid, and it did bring the temp down by 4 degrees. But still not enough for it to be worthwhile. Probably quicker to just put it in the freezer 😅
You should past the water from the looled cup into the alluminium blocks and then back to the cup. This should make the water cool downt to much lower tempetures.
you can achieve better heat transfer without the pads just dry or small drop of water(when it evaporates there will be bond) or best option use thermal paste but its pain to clean up thats why i use the water method for my testing 80W peltiers
Yeah... Thermoelectric cooling like this has it's benefits, mainly how there's no wear and tear, and since cooling is directly proportional to applied current, it's easy to control precisely. But it's got dogshit energy efficiency and is actually quite limited in how much heat it can pump away, largely because the hot side inevitably heats up the cold side from inside the device, meaning it actually becomes less and less efficient the more you crank up the power.
Would stacking the peltier modules to provide a lower cool side temperature improve the amount of cooling to the liquid? I know by stacking the modules you can get lower temperatures however it also requires adjusting the power the modules use since they are working harder
Along with all the inefficiencies in this design, don’t use thermal pads on the hot side. Use thermal paste, you’ll get more efficient treatment transfer of heat, and if you want better cold side performance use a liquid metal like thermal grizzly kryonaut. Although this is almost useless with the poor efficiency of the Peltier.
You fluid is not in contact for enough time with the cooling mass. You'd be better off creating a maze of small OD copper tubing and then submerging that in dry ice and then pump the fluid through that.
I did some quick back-of-the-napkin math, and for a can of coke, to cool it from 17 to 8 degrees requires 14 kJ of energy. If the peltier device was 100% efficient (which it very much isn't) it would take 3 minutes and a bit to cool the water. The peltier element is much more likely to be around 20% efficiency or less, therefore it would take around 15-20 minutes to cool the can of coke. The issue is really that water has a very high specific heat capacity of 4.2 Joules per gram Kelvin, meaning it takes 4 joules (or 4 watts for 1 second) to cool 1 gram of water 1 degree. Helpfully, a gram of water and a milliliter are pretty much the same.
Or in other words, to cool the can of coke in 2 minutes with a 20% efficient peltier element would require nearly 600W power draw.
Now this is my favourite kind of napkin maths! Thank you so much for describing this - this is unbelievable useful. At least now we can understand a ballpark upper range of how long it might take under an ideal setup. So really, even with a couple of 300 watt power supplies, and a number of Peltier modules with optimal cooling, we're still looking at a period of time longer than just chucking it in the freezer for 10 mins. I'm glad I didn't continue eking out minor improvements in efficiency! Really appreciate your help here ❤️
Considering he was running those poor cells as hard as he could, and that he didn't provide any insulation, 20% seems a fairly optimistic estimate... I would have guessed 5%, or even less
@@Beregorn88 I'm not an expert on peltier elements so I just looked up typical efficiencies, and 20% seemed to be in the middle of what people were saying, so I went with that.
@@JamiesBrickJams Cool project! I never considered a lego fan ;)
Several more forms of thermal loss:
Thermal pads are convenient and clean, but nowhere near as good at heat transfer (especially to the ceramic of a peltier module) as thermal grease. You could likely drop the hot side's internal temp substantially with better TIM (Thermal interface material) which would increase your efficiency by an order of magnitude. Even junk thermal grease is typically on par or better than gap pads.
Your metal cup is acting as a heat-sink heating the water using the air.
It might be that those water blocks just aren't great at transferring heat. Thus, the cold side may be getting far colder than the water. Peltiers are most efficient when the temp difference is minimal so stacking two water blocks on one peltier then a single block on a second peltier may net you some more performance. (so, pump -> top block 1 -> bottom block 1 -> block 2 -> cup. Here where both "block 1"s are on one TEC and block 2's are on a second.
Peltiers can actually be quite efficient, but typically at low power at small temp differentials. I have achieved 38%+ with a good test setup and name brand modules. Also, using cheap modules I have gotten to -30+ degrees F. You can use detect radiation and cosmic rays by building a "cloud chamber" with this method.
@@nathanielhuggins9254 True, those thermal pads are pretty useless. Also, could be wrong, but I think they depend on getting hot, at first, to mould themselves around the CPU surface they're usually supposed to be cooling. If you're dealing just with flat surfaces, much better to use thermal paste as you mention. And maybe spring pressure or some elaborate Lego mechanism to keep them firmly pressed onto the heat sink. CPUs use the sort of springs you could do the suspension on a monster truck with, they have power!
honestly for the inefficiency of a peltier device, you're more than likely better off just pouring the water in a shallow bowl in front of a regular fan and letting evaporative cooling do the work instead
Add one of those bricks with holes into the bowl,it will soak up the water and give it more surface area to evaporat
@@yixuan7043just add bio balls, they add a ton of surface area
Ha I actually kind of like this idea. I'd be interested to know how effective this would be. It'd certainly draw way less power over time
@@JamiesBrickJams Try to see what will happen if you put some water under a vacuum, then it should turn into steam faster, right?
for the peltier system, you'd have to wait until the water cooling block is about as cold as the peltier.
although if you had an exchanger, you could have a closed cooling loop that's continuously cooling only a small volume of water then transfering the cooling to your drink.
That's what I figured, I did try to wait about 5 minutes to drop the temp, but it seems like the block just refused to get low into the minus figures. I've a suspicion that the block actually heats up the cold side too much, causing it to run way less efficiently. It seems to drop the temp difference it's able to create. But in general I'm sure you're right that a slower trickle passed through it should work better! Or perhaps multiple trips through the system
@@JamiesBrickJams I have read the comment with the calculations. But my idea for improvements would be a bigger peltier and cooling block, and 2 of those peltiers so you can sandwich the cooling block between them. Still, for proper cooling you need lots of power. Same as with heating. I gues you should look into constructing of a Lego heat pump 😅
Ausome
@@captainevenslower4400 That was my thought too. Sandwich the cooling block and then insulate the exposed sides.
@@JamiesBrickJamsI think if you sandwich the heat block with Peltier modules, the block would become more efficient.
1:16 - Peltiers get more efficient at lower power so getting a bunch of them and running them at 50% power would be more efficient than running the equivilent single one at the same power, it also helps to move the heat away from the peltier rather than dirtectly cooling it but that gets more expensive.
2:46 - looks like you are already working towards that, 👍
Ah that's really interesting, thanks for your comment! I do have a lot of these modules, so perhaps running 6 of them at half power might work? Might have to invest in a few of those larger water blocks and attach multiple units to it
@@JamiesBrickJams And a few other things, you don't need that beefy water blocks nor your silicon pads. Both of them increasing temperature mass and the time, in the end. Also, if you want to squeeze as much COP as you technically can - you should isolate all your cold side from the ambient, and definitely start to use double-sided glass, cuz you should keep the already cooled liquid as far as you can from ambient temperatures. And definitely, pouring more energy into peltier modules isn't a great idea too, because from their poor efficiency, let's say 20%, remaining 80% are gonna be heat, so more power you're make them chug - more heat they gonna release, and heat losses doesn't give a flying fk where's your cold side.
Because of that, peltier modules is really useful only in car can chillers, because they're too weak to actually cool them, but their power output is viable to keep them at the same temperature (and with insulation of the box as well...)
You are dealing with enthalpy. Water holds a huge amount of btu’s. You are trying to move btu’s from the cold side of the peltier chip to the other. The chip surface may be cold, but it’s ability to move btu’s across to the hot side is almost as inefficient as its electrical use.
I'm pretty sure you're absolutely correct here, and thanks for confirming what I was suspecting. These things are so inefficient and I'm amazed to see how many silly videos seem to suggest you can make reasonable air conditioners and other ridiculous claims using these. And water seems to be particularly challenging to draw heat from too. Thanks for your comment here 👌
I came here to say the same thing.
@@JamiesBrickJams Pin Me!
I think it might be way more efficient to use some cold water, ice, salt and a bowl big enough to contain the can and the rolling mechanism.
Using silicone as a thermal pad will have definitely impacted the performance of this device. Silicone is not a good conductor of heat and is actually more of an insulator. Theres a reason why silicone oven mits are so common nowadays.
Dude, the things I have seen you do with legos really impresses me, please keep making these incredible videos.
Aw thanks, really enjoy comments like yours 😊 Will try to keep the ideas fresh!
"Lego" not "Legos"! The plural of Lego is Lego! Ask the Danes.
I think you could make it work better by creating a loop and cycling your whole drink through it multiple times. Maybe also using thermal paste on the peltier will give you better transfer
exactly what i was thinking
Finally someone thought about thermal paste
nah, thermal paste is overkill for how little heat is being moved.
@@ameteuraspirant I think 40 watts of heat on a small piece of ceramic will get hot. That's like a CPU working at 25% capacity
I had a similar idea to the last.
run the tap water through a air/liquid heat exchanger before using the water.
so during summer, you can have cold air blowing on you while you wash your hands with cool water.
or during winter pre-warm the water before it hits your hands.
i have used and played a lot with Peltier modules, the main problem i see is the silicon pads, even those thin ones you use are less thermally conductive than direct contact without thermal paste
the way i usually stick them on a heat sink without a way to clamp them is a dab of superglue on each side/corner, and i recommend using a tiny bit of thermal paste (with the next to non existent pressure the glue applies, you really don't want a lot), while the glue is drying make sure to apply a LOT of pressure so it can have as much pressure as possible when dry to help thermal transfer
also, if you use those water cooling blocks, you might as well use some clamps on them to increase pressure (and use thermal paste, I'm serious when i said those pads are really poor thermal conductors)
also, if you run them at a lower power (which makes them a LOOOT more efficient), you can stack them to have much colder temperatures (but like 4-10 times less cooling power(it's like top speed versus acceleration in a car, but your transmission is made of paper, if you stack to many Peltiers and put too much current through them the lower ones can't sink the heat fast enough and all you get is thermal runaway as they get hotter, more resistive, make more heat, and yeah you get the picture))
you could have it cool a larger reservoir of anti freeze, and run that through a closed system. Then run the chilled coolant through a liquid to liquid heat exchanger that you put into the drink.
I've gotten something like this to work. I used a skived copper heat sink. The thermoconductivity of copper is nearly 400 W/m-k while aluminum is nearly 240 W/m-k, meaning the copper will take away a lot more heat. Copper heatsinks are a lot heavier and costlier but they work really well given the space.
Woah that's really cool, and well done! A copper heat sink sounds like quite an upgrade
@@JamiesBrickJams By costly I mean $30-$40. It'd be cool to see if it works for your design.
You should try joining the heatsinks and peltier blocks with thermal paste. This will let the heat flow better and allow the heatsinks to have equal amount of cooling. Also thermal paste is better that the squares because it is like a thick liquid and fill cracks and spaces better. I got 7c water with a large heatsink and fan with a small peltier at 50w.
It would help a lot if you infinitely circulated your drink through the blocks rather than just one pass. That way it would get cooled a lot more because of multiple passes through the cooler
Someone else doing something similar did the exact same thing you did at the end but had the same coolant recycled repeatedly and cooled it down in a tank rather than the sink which would probably provide a helpful buffer.
use only one water block and cool it from both sides
this also stops one cooling module from over heating
Honestly for better thermal transfer I would onto both the cooling surface and the radiator surface use small pads as I saw you didn't for the transfer to the water block. Keep in mind more surface area for thermal transfer to a liquid would be best as well to have some fins in there. Also furthering that the transfer speed of the pump may be warming it back up as well. IDK if this helps much but love the vid!
The water cooling at the end seemed to have worked well. You should be able to cool water with a big surface and some airflow, like a baking sheet full of water and a fan.
Lego is best for structures but limited in energy density. So you might take advantage of a larger surface area.
Insulating the hot from the cold side should help and maybe using "better" thermal pads most standard thermal pads are pretty crap for going bellow zero they lose their elasticity and stop cunducting the residual heat as efficient, the hot side should be ok with thermal pads. I would use thermal paste for the cold side. Also using two seperated cooling blocks might reduce the efficiency even more i would opt for a single double wide one.
Ah that's interesting, I could certainly give it a try with thermal paste and a larger block. Cheers for the suggestion 👌
Used to have a single-can sized "fridge" that was just a fan, heatsink and peltier device powered by USB 2. Since I have 0 use for it I just disassembled it for parts.
Nowadays you can buy cooling bags for cans and bottles, probably even better.
That's cool, I wondered if those little fridges were just Peltier modules in them. And you're probably right, I'd imagine a cooling bag is much more effective. Certainly quicker
The Peltiers don't produce a massive cooling effect. Insulation is the key! Cut polystyrene appropriately to insulate out heat wherever you can. Also looks like the pop isn't spending enough time in the cooler blocks, perhaps recirculate it around a couple of times? Or else slow down the pump, but I suspect with a peristaltic pump, slowing it down would just stop it working as there's a certain amount of back-flow.
Maybe have the pop recirculate round and round, back into it's jar, then after a few minutes activate a second pump that actually serves it into your cup. Or pour it. And the cup, too, could do with being in a big block of expanded polystyrene. Polystyrene everywhere! Or some sort of insulation at least.
Think how long it takes one of those Peltier mini-fridges ( _with_ insulation) to cool a can. It'll be half an hour or so. Hence you need to recirculate the pop, a couple of minutes to do a whole cupful isn't long enough.
You make me happy, this stuff is extremely hard, but you make it useful. You can help people with your stuff, great job!
Aw thanks a lot that's lovely to hear 😁 Most of my contraptions are totally useless in a practical sense. But the concepts are fun to mess with!
@@JamiesBrickJams Thank you for responding, I'm not usually noticed by RUclipsrs like you, your the third RUclipsr that responded. Thank you sooooo much!! Also could you try to make a hose to water plants? Thanks again!
@@JamiesBrickJams Bruh I literally nine and I'm already soooo interested in stuff like this, thank you for coming to RUclips and sharing your inventions!
Thermal pads are pretty bad at transferring heat, you should really avoid using them. Even a bad thermal paste is orders of magnitudes better. Use a good thermal paste instead and keep the mounting pressure high, this should dramatically help. This goes for both sides of the peltier, your bottleneck is most likely how fast you can get heat away from the peltier. The hotter the peltier gets the less efficient it becomes, creating a cycle that heats more and more. Thermal paste
Ever heard of ice?
You should have flipped the tiny fan under the heat sink the right way so it’ll perform better with the heat sink
aside from the bottleneck of the peltiers, it'd probably be more efficient if you were able to isolate the hot and cold sides so the temperature isn't able to return to equilibrium, say as a liquid in a closed loop, it'd also help if the cold side was enclosed so the ambient temperature wasn't constantly warming the water back up, say, an insulated box with a handle for easy acce- I'm describing a mini fridge 😅. jokes aside, I'd love to see a lego powered heat pump fridge.
You should've connected the output and input to the same glass so you could have gotten circulation to cool it down
Love these videos!
Thanks a lot man, love your videos too!
8:44 thermal pads arent great at heat transfer, thats why we dont use them on computer processors (we use them on memory and other components though because the components tend to be oddly shaped and don't output much heat). Additionally the heatsinks are squished down via mounting pressure which is incredibly important for thermal pads and pastes to work well.
I'm curious if your abomination would perform significantly better if you had used a thermal paste like Arctic MX-6, or even a graphene sheet (Thermal Grizzly makes some). Alternately there's also PTM7950 which goes on like a pad but then melts under load -- but thats meant for a permanent installation: costs more, performs better, and doesnt need replacing, but a bit of a waste on a project like this.
That said, someone else calculated the cooling efficiency of cooling the water/drink and yes, water is quite difficult to heat or cool (majority of energy during cooking is literally just heating water) Like it's so high that we opt to move it mechanically when it freezes in winter (that is: we shovel it) because its less energy intense than attempting to melt it. Its thermal capacity and conductivity is amongst the best materials we know of (amongst other attributes, water is truly a chemical miracle), it would take an insane amount of time and power to equal just running cold water over the can like you did at the end :)
use thermal paste instead of thermal pads, they are much better at transporting heat. Also apply pressure from the Heatsink to the Peltier to improve the performance of the pad
Not a bad idea, I could give that a try!
@@JamiesBrickJams and as i now looking at the device i would also recommend to use something like a CPU cooler(like that one in the beginning of the video) because they have heat pipes wich spread the heat more efficiently,so the whole surface area is used for cooling and not just a small point. For your application i think you could scavange the heat sink from a old GPU like the gtx670 because they are really flat and have a large surface area so it will fit in your current design without major changes
@@JamiesBrickJams another idea is to go for water cooling but for that you will need a radiator wich further complicates the device. I think just dumping the hot water in a large bowl filled with water could also work since you are only running the peltier at 17w
Please use thermal paste like arctic silver 5 or Thermal Grizzly Kryonaut, it pains me to see the thermal pads instead of pasteeee @@JamiesBrickJams
Wouldn't it be even more efficient to just... put the can in a bucket of tap water?
That'd be quicker than the Peltier device for sure! But I tested putting a can in still water (and not moving the can), and it takes a fair bit longer. Also when the water is sitting in something for a while, the water heats up rapidly, so the drink can't get as cold. I'd imagine your best alternative is just chucking your drink bottle into a bucket of ice or ice water. But I enjoy overengineering things 😁
@@JamiesBrickJams The movement of the water/can surface is key. The can in a still bucket will essentially warm up the water right around it and that severely affects how fast it can cool. When you spin the can and water super fast then you are using the "cold" of the entire bucket of water at the same time
Try looping the water through the system multiple times therefore it will pass through it more and cool down more and then have an output where you can release it when you want and not immediately because it will take some time to cool down a fridge does the same thing where it loops it several times
Uhm so fun fact the last machine you built actually exists irl and uses ice to cool down your can
Oh that's so cool, I'll see if I can find something like that for inspiration. I guess an ice bucket would work well if you can pump it over the can
@@JamiesBrickJams It basically uses ice and cold water in an enclosed space, kind of moving it around while rapidly spinning the can and that absolutely blitzes the can down to a couple degrees within a minute or so I think.
If your fan blows air through the channels of the heatsink, instead of just blowing it onto the top of the fins (against gravity aswell), you'll have more efficient use of the heatsink.
A low-tech proposal for cooling the drink, along the lines of other comments: put your can into a small container, preferably made of aluminium or copper (the thermal conductivity of copper is roughly twice that of aluminium) with 3-4 mm of water surrounding the can. The container should have an upper section with fins, i.e. a heatsink section, where the bottom part of the fins are submerged in the water. Now blow on the fins with a fan. This way, you are assisting evaporative cooling by forced convection and aiding the natural convection in the water by the high thermal conductivity of the (aluminium/copper) container. Hope that makes sense, good luck and thanks for some very entertaining and high quality videos!
You can use thermal paste instead of silicone pads, thermal paste has a higher thermal conductivity so you can transfer more heat
A few folks have suggested this, so I'll definitely give that a go, cheers!
I would have figured out a way to use thermal paste as those thick pads are holding it back. Still cool though. You could even use tooth paste!
Find a way to clamp the waterblocks down as that will help a bit.
Woah you can use toothpaste?? Haha that might actually be worth a try
Let the water block cool down so all of the heat gets pulled from the water block rather than the water. Less thermal mass to cool down at the same time
Who here keeps a cooler or minifridge for drinks and snacks beside your gaming setup?
Me
Thermal paste would help somewhat as the most efficient thermal pads are still worse than cheap paste
I had a project about Thermoelectric Coolers, it was hard to generate cold water but i suggest to do the opposite. I noticed TEC's are better if you generate heat using ice that the practical use are making hot or warm choco/coffee that will be use to places with snow. The device can be a portable drink heater...
I think in this way, it will be more efficient.
You can just take a bunch of ice and a little water and quickly spin a can inside of it. That cools it down really quickly.
You should look into how PC liquid cooling mechanisms work, it might help provide a bit of info. I do suspect conductivity to be the issue at hand though I don't know how exactly to fix it.
Who needs a drink cooler when you can have a fan blowing on a Lego water fountain for instant refreshment?
Hey man, I saw this and the following rang my bell through the whole video. You have the hot side of the peltier facing downwards. If i were you I would repeat the measurements but turning upside down the peltier-group, also making sure the heatsink fins are facing up and trying to direct the air pushed by the fan through a duct from the side through all the fins of the heatsink. Surely most of the heat transfer is thermal conduction (and the orientation of the heatsink in space shouldn't affect this), but doing this may help somewhat in the convection part of the heat transfer. It may not sound so appealing because you need to work the other part of the design out I suppose. I hope this helps you!
i feel like its not about the contraption, its about the Water thermal capacity. i think its one of the substance with the highest. you need to add lot of energie over a long period of time to make a change. and its reversible
you could fix it by add maybe a pack of ice optionally on top of the fan to cool down the air and also 3d print some those thing use in car intakes to direct the airflow only up
I guess I could also put ice in or around the drink cup too 😅
To conduct heat better I suggest applying thermal paste intended for CPU's instead of silicone
You basically just made an intercooler, as long as you use the proper fluids, I wonder if it could cool an engine?
now put multiphase in the heatsink -and for overengineering, in the fan blades too 😁
and I guess you could have a light spray of mist -which improves everything
maybe use Good Thermal Paste like the Artic MX-4 and find a way to press the heatsink and cooling block on the white element. This would make it better. Run them on parallel and it would be a lot better. Maybe use some insulation too
I love the winter water it’s free here in New Zealand as well in some locations, Including mine
It will be more efficient if you used high thermal conductivity thermal paste made for computers. Also, using the CPU cooler you showed earlier in the video would be much better than that aluminum heatsink at it has a higher fin density.
"Somehow we're squirting out the other side too" 💀
"We were sucking and blowing at the same time" 💀
"Both sucking and blowing at the same time"
Can you sandwich the cooler block between 2 peltier devices?
Also slowing the pump down might help as it lets the water spend more time in the cooler
Get some water. Put it in a mold of your liking. Then put the mold with the water in a freezer. In a couple of hours, check the molds. The water should have turned solid. If not give it some time. When the water turns solid get it out of the molds. Put the now solid cold water in a cup and pour your drink in the cup.
Bam! Cold beverage.
The biggest issue is that you're passing water over the cooler way too fast.
I'm surprised the tap worked that well.. but actually.. it kinda makes sense from the surface area to volume ratio and timing.
what you should have the beverage in a loop so the cold side of the device can actually get cold
new subscriber, i like your content. it's fresh and the way you speak isn't too loud it makes this video relaxing to watch
Thanks for joining, and I appreciate your comment. I'll continue to keep my voice down for future vids 😉
the two peltiers need to attach to one fluid cooling block, it'll run a lot better
That does seem like it would have been a good idea - cheers for the suggestion!
Water has a huge thrmal mass, i suggest letting the water cycle a couple times
I'm only realising this properly now 😅 Someone did the maths, and there is an absurd amount of thermal mass to pull from a drink
He finally uploaded
Ha I wish I could work on these more often, but life is always so busy 😅
Fun fact 0:04 , I have the same thermometer as you. Its from Amazon.😂
Haha sure is 😁
I’ve made on of these and it runs at 6v and 1amps which is 6wats and it cools 20 liters of water in a tank to a freezing 9 degrees
Cool the hot side with water cuz more heat goes to the cool side and wait until the water blocks get cool. Additionally you could use stronger peltier modules
Ooooh I like that idea! So water cooling the hot side? Damn I should have tried using those water blocks on the opposite site too. Great idea, I'll give that a try for sure
Steel Ice in a tumbler , pour the drink in lock in with second tumbler (like a bartender before they shake your martini) tip back and forth between the two tumblers about 4-6 times , pour in fresh glass. Use legos to tip the tumblers like a teeter totter
Ooooh that's a cool idea, I like it! 😁 That sounds pretty straighforward
it might of been better to use thermal past and compression fit the pltas
slow down the pump it will take slightly longer but slower allows for more heat transfer
How about you use thermal paste or even liquid metal instead of thermal pads for thermal transfer. That should help a bit
For a start: Peltiers are really disappointing.
1:30 - You have put a metal jug in front of a fan... the fan is heating your liquid.
Are you sure that silicon pads are thermal efficient? Try thermal paste and a better fixation of the peltier to heatsink and block.
Make a thermal isolation on your block.
Make the pump run slower, the slower the colder as you give time to peltier remove the heat.
Check if your fan is moving enough air, the colder the peltier hot side the colder will be the cold side.
One thought is that you have the hot side of the peltier device on the bottom, and we all know that heat rises, so the heat from the hot side of the peltier device, along with the heat from the heat sinks, is heating up the cold side of the peltier device, thus negating the temperature difference. Try building it so the cold side of the peltier is at the bottom and the hot side is at the top so the thermal difference is assisted/maintained by the laws of thermodynamics.
Hmmmm that might not be a bad idea, cheers for the idea. I see no reason why I couldn't run the cooling beneath the module and extract heat from above. As someone else noted, it might even be worth using water to cool the hot side!
@@JamiesBrickJams oh and water in Ireland isn't free, to quote Uisce Éireann, aka Irish Water, "it's a precious resource that we're all responsible for".
Although, given the number of mains repair work jobs logged on their website, Irish Water is pissing it into the ground due to a complete lack of maintenance over the years, especially the years before the Irish government's failed attempted to privatise the national water supply, using their Garda thugs, in an attempt to introduce yet another stealth tax on its citizens. ✊🇮🇪✊ 🇮🇪✊ 🇮🇪
True, and that's one of the main reasons I don't want to waste water. Having lived in South Africa where it is a scarce resource, I really don't like the idea of being frivolous with it. But not having a number appear on a bill makes it feel sort of 'free' 😅
@@JamiesBrickJams Not to bitch too much, but the Irish Government is like do as we say, not as we do.
You have that pillock Eamon Ryan telling all us plebs to walk, cycle, use public transport, or get small electric cars, while he drives around, alone, in a VW transporter. The level of hypocrisy just keeps getting higher and higher, like 100/10 high FFS
5:44 *Austrian painter has joined the call*
Good lord 😂
0 likes, but a comment from Jamie?!
I would be more impressed if you used vaporization cooling (the one that is used in air conditioners and refrigerators) instead of peltiers
Obviously Peltier heaters aren't at all efficient. But what we are really dealing with here is a specific heat problem. Water (and water-based beverages) is *very* resistant to temperature changes, whereas air and aluminum are not. Because we are trying to cool water essentially by transferring the heat to aluminum and air, you would need a much larger quantity of air and aluminum cooling to match the amount of heat in the water. Even without losses of efficiency in the cooler itself, the mass of air and aluminum required is ridiculous. The other option is water cooling your water, which is exactly as ridiculous as it sounds.
imo it’s the silicone stuff.. Just allow them to get direct contact or even add some thermal paste🤷🏽♂️
Maybe try thermal paste instead of pads for better heat transfer
why dont you just let the drink flow through the system multiple times?
That's a good idea - I actually did try different speeds, allowing 10 minutes to slowly pump the fluid, and it did bring the temp down by 4 degrees. But still not enough for it to be worthwhile. Probably quicker to just put it in the freezer 😅
You should past the water from the looled cup into the alluminium blocks and then back to the cup. This should make the water cool downt to much lower tempetures.
Not a bad idea to perhaps keep the fluid running in loops until it's cool enough 👌
Maybe using a faster motor like a black one.
You are overwellming the heat sink by using three water blocks instead of one and also do it suck the water from a cup and put it back on the same cup
Dude your fridge is warmer that 3.5 degrees? that’s kinda warm man I’d maybe set that a bit lower
Use cooling paste instead of silione, make the layer as tiny as you can. grtz
I feel like the glaring issue is expecting to go from warm to cool in a matter of minutes or seconds instead of trying to *keep* something cool.
Instead of thermal pads you'll get a better results with thermal paste/compound
I'd love to see an A/C made in lego
Haha it's certainly possible, but it'd likely be the world's most inefficient AC unit 😅 and would have an absolutely insane power draw for it to work
@@JamiesBrickJams Just need some wd-40 and it will lower the friction of lego, but yeah it will be a bit hard, considering the pressure necessary
Use the pump to remove heat from the heatsink, like a water cooled PC
Don't use the blue thing, use the thermal paste instead
It will increase efficiency
you can achieve better heat transfer without the pads just dry or small drop of water(when it evaporates there will be bond) or best option use thermal paste but its pain to clean up thats why i use the water method for my testing 80W peltiers
Thermal paste is definitely an option, I could try that 👌
Yeah... Thermoelectric cooling like this has it's benefits, mainly how there's no wear and tear, and since cooling is directly proportional to applied current, it's easy to control precisely. But it's got dogshit energy efficiency and is actually quite limited in how much heat it can pump away, largely because the hot side inevitably heats up the cold side from inside the device, meaning it actually becomes less and less efficient the more you crank up the power.
Nice video
However if you pay taxes your water ain't free
Would stacking the peltier modules to provide a lower cool side temperature improve the amount of cooling to the liquid? I know by stacking the modules you can get lower temperatures however it also requires adjusting the power the modules use since they are working harder
you need to screw the block to the peltier for better thermal transfer. Also use thermal paste
That's not a bad idea!
2:38 my humor is broken😅, great video though
😂
What about making a closed circuit of the cooler block and dropping that into the cup tk work as an external cooling unit
Why not cool both sides of the aluminum cooling blocks? One cold side and one room temp side seems... counter productive.
Along with all the inefficiencies in this design, don’t use thermal pads on the hot side. Use thermal paste, you’ll get more efficient treatment transfer of heat, and if you want better cold side performance use a liquid metal like thermal grizzly kryonaut. Although this is almost useless with the poor efficiency of the Peltier.
Did you know that peltiers are very inefficient compared to vapour compression systems (you know those one’s that use refrigerants and compressors)?
Sorry for my blotchy typing because my iPad is as slow as snails
You fluid is not in contact for enough time with the cooling mass. You'd be better off creating a maze of small OD copper tubing and then submerging that in dry ice and then pump the fluid through that.
6:33 Nice knife ;)
Haha she's been a useful old thing. Does yours still get any action?
@@JamiesBrickJams only on special occasions
Try stacking the peltier-elements
Hmmmm I wonder if that works?