We take our previous TEC refrigerator project, make some improvements, add more cooling capacity and build a freezer. We then freeze several trays of ice.
Previous video - • EXTREMELY LOW TEMPERAT...
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Thanks for watching!
I'll say it again, "This channel is bewildering when it comes to content and production quality. Thank you to Tech Ingredients
Unlike many others, they did not seem to have much of a learning curve either. They just showed up out of nowhere 5 years ago and started making high quality content.
@@Jesses001 I agree entirely. It's simply amazing!
It's also very annoying that I left out the closing quotation mark in my original statement.
@@lank_asif so go edit your comment then
"
This has become my absolute favorite KZhead channel because I'm 100% confident he will never start using clickbait thumbnails and titles as most everyone eventually does. Also, I'm confident he will not ever say "smash that like button or smash that subscribe button". Then there's the videos which aren't full of edits between every sentence. It doesn't feel like a performance like so many channels have become....just interesting glimpses into someone who's passionate about testing his ideas.
I am constantly surprised by the professionalism that this channel clearly shows. This applies not only to the planning of a project, but also to the subsequent implementation. Thx for so many great projects and your videos to this projects.
There are so many videos in this channel that deserve a place in any post-apocalypse knowledge base. Great work!
Man, not only is it inspiring to watch this channel, it is inspiring to see the viewers becoming inspired too!
The curiosity, passion, and desire to explore different concepts on your own, in the real world, much of humanity cannot grasp very easily, and without that, life can be very lifeless for some of us. This channel among many, steers this great ship toward greater shores.
Meh. It's penance for the hundreds of litres of fuel pissed away for viewers' entertainment, and insufficient at that.
‘Skills and knowledge’ help. As does time and money lol. But yea, we should be feeding our curiosities and entertaining ourselves rather than always letting others to always do the entertaining. The constant rollout of TV shows seems to keep most addicted to the meaningless mundane
@@fun_ghoul "hundreds of litres of fuel pissed away for viewers' entertainment, " What would be any better use of the energy you claim was pissed away?
@@sailingsolar TBC, I wasn't talking about in _this_ video. Go check out how many TI video thumbs have fire in them, and then ask yourself the question you just asked me. Ouf.
@@muntee33 Is a fridge-building video less mundane or meaningless if watched by a person who lacks any of the requisites to make it? Just sayin'.
It's like watching Mr. Roger teach scientific and engineering theory and principles. Its so watchable and yet, conceptually advanced.
Thanks!
The heat dump is like a reverse Yoder loop. Thats pretty cool.
I honestly never comment on videos, but I've watched just two from this channel and I am blown away! This content is extraordinarily beautiful; I wish I'd stumbeled upon it much earlier. Frankly, I'm shocked that these videos don't have more views and the channel more subscribers. Thank you Sir, I genuinely hope your channel grows to become a great success!
Thank you, and welcome aboard!
What's beautiful about a freezer that uses 10 X the power of a commercial one?
even watching this guy fill ice containers is fascinating... seriously though great content as always.
I'd love to see how efficient these are on a hot July day.
We need solid state EVERYTHING and CHEAP ELECTRICITY to run it all on Awesome content!
10:00 Always fun to geek out on your stuff. That is exactly what would happen. I don't think that people intuit that freezing--meaning the actual phase change--is an exothermic process. When there are minerals present, there are ubiquitous nucleation points provoking the phase change on the way down, but deionised water would delay phase change allowing the temperature to drop several degrees below zero while still being in the liquid phase. Just before the phase change starts, it releases heat into its surroundings, bringing the temperature back up to 0, which is the actual freezing point. Once the phase change has finished, the temperature drops again. This whole cycle is what was detected by the thermistor. I was raised in the Sierra Nevada mountains, and we had wilderness survival training in the 7th and 8th grade. Our teacher demonstrated this phenomenon during one the winter survival outings. And because it was so cold out, it didn't need to be in an enclosure, so we were able to directly observe it happening.
Hit the like button and then watch the video! ...because it is always quality content in this channel
And that's the truth.
You got that THAT right! Nothing like a super well educated engineer who ALSO has SERIOUS educational abilities.These two particular talents are not always easy to find in one package!
I'd love to see you guys tackle the problem of how to insulate a workshop cheaply! I and many others have metal shops or pole barns and the cost to insulate them is insane! You have so many ideas on how to do things way cheaper than normally and I can't afford 6 grand to do my lil shop and that was a buddy deal from a friend that does it for a living. Thanks for all the great vids!
We'll give that some thought. Thanks!
Your answer @stevejuststeve9929 is to make your own StyroAirCrete and make it as thick as your heart desires/wallet can afford. I’d shoot for 8” personally. Create a continuous insulation barrier and be blown away.
Even though this is less efficient than normal fridges, living out in the mountains makes this very attractive for the self repairability and ease of maintenance.
Agreed
For some time now I’ve been mulling over the idea of building a good sized cloud chamber in a coffee table form factor. I hope to use REMs above and below the glass move particle sources around. The work you have done here has really renewed my confidence in going the TEC route.
Great!
@@TechIngredients (3yrs later) Sir, given your propensity for detail & accuracy, I'm shocked you didn't list parts dimensions, or even a materials list! Thank you...🇺🇸 😎👍☕
A true Engineering channel. I loooooveeeeee iiiiiiiiiiiiiitttt !!!!!!!!!!!! I can watch this kind of stuff all day.
This channel is what highschool or university level science should be like. I love it. Keep the content flowing.
I dont normally leave comments on KZhead videos. In Fact I have probably watched an unknown amount and NEVER said a thing .. but let me tell you. I cant express how much I appreciate your recognizing and explanations of the details. This is great! I want to support your content, lets bump UP those views. Ill Like support and comment on this ANY day. LEGIT, Thank you so much for being you and creating this content!
Thanks!
Bam! Once again, you all have knocked it clean out of the park! Well done (as usual). Please, keep the *FANTASTIC* work!
I've really enjoyed this series, thank you two for such great work.
Recently found your channel and I’m enjoying the thoroughness of your topics/projects. Appreciate the detail you put into your content!
Great video. Nice calm, measured presentation!
Thanks!
Thanks so much for the assembly timelapse in the beginning!
You're doing some very interesting work. Can't wait to see the desiccant based system and your take on swamp coolers.
I like this channel. Its just technical enough without losing me.
Perfect!
Thank you for sharing all your amazing work. It is beyond fascinating and your dedication is impressive.
Very much looking forward to the desiccant A/C build! Your sourcing tips are always great, and should be particularly helpful on that topic.
Totally inspired by your work!
After watching hundreds of videos on youtube about peltier cooling, I have to say you did the real test with real load to be cooled. Peltiers are inefficient but considering space constraints and target requirements they still do a great job
I've been an electronic bench test technician for over 10 years. I love math and electronics. I like that he has the ability to articulate in such away that even people without a degree in electronics can follow along. Thank you for bringing your knowledge to the table and allowing us to learn from you.
Thank you.
Always interesting and well presented, with the concepts clearly explained. Ramp up the power and ramp down the temperature! And I love your accent.
This channel has intrigued me alot! Great detail in your work with components we can all purchase and make ourselves. Looking forward to your next video!
Thanks!
I was doing some researches on the Peltiers recently, and your work save people like me time and money. I really appreciate your work and I hope you keep going. Thank you.
I wonder if channels like this ever take a moment to consider the lives they are changing
😋
Another excellent video, thanks for sharing! It would be awesome to see a project where you cascade evaporators and see just how low of a temperature you can reach.
THIS CHANNEL IS AMAZING YOU AND YOUR SON ARE KILLING IT!! Great job
This is the best channel. I have done some of these projects. If I had seen these videos prior to doing them, it would have saved my ass on more than a few details. Thank you, you are doing a great public service.
this is fantastic! The first time I saw snow I thought about a system like this, but for PC cooling. couldn't find anyone talking about a system like this, but now I find this and I'm super happy about it.
The Mr Rogers of tech. Here we have some happy little ice cubes. Love this content! Keep it up
Thanks!
No one's done the math yet, so here we go: What was the heat pumping coefficient? The temperature crosses 0.0 for the first time at 5:16. The temperature departs from 0.0 at 8:31. That's 195 minutes or 11700 seconds. Since the whole unit was using 219W, it used 2,560kJ during the freezing period. It takes 334 kJ to freeze 1L of water. 334 kJ / 2,560 kJ = 0.13 So the heat pumping coefficient was 0.13. (Btw, there's a bunch of missing frames around 8:31, so I plotted everything available from 8:30-9:00 and drew a line back to 8:31)
so how does this compare to your average consumer freezer?
You didn't include the heat pumped out bringing the water down from ~20 deg C to -5 deg C before it started freezing nor that from cooling the ice from 0 to -5 deg C (or the heat of the air, but that's probably negligible). Still doesn't make it a great efficient option.... just not as bad as you calculated. It's another ~105 kJ for the cooling of the water as was observed. Making a bad assumption that ice needs the same heat pumping as water adds another 21 kJ, so... total of 126 + 334 = 460 kJ. So CoP = 0.18.
I'm sure it was intentional that he did not address that. I looked into Peltier options when I was researching the tiniest fridge for my solar setup and nothing came even close to compressor bassed Systems as far as efficiency goes. I currently use a compressor based mini fridge, only 1.2 cubic feet but it uses about 80 kilowatt hours a year. I've had it for about a year now and haven't seen anything on the market come close. I hope that changes. We need high-efficiency at reasonable prices. If you could show me how to make one of these: www.amazon.com/dp/B076S52ZG2/ref=cm_sw_r_cp_taa_i39pDbJE2E9PE without losing efficiency (150kwh/yr) I will be a happy camper! Literally...
@@dacelooper At $1000 purchase cost for that freezer then even with the low efficiency of a TEC if you have cheap/free electricity then it's quite possibly more efficient cost wise to go with a TEC.
@@isaaclester3318 The big issue is these device work very poorly in high ambient temperatures. Very ineffective in tropical temperatures when the ambient temps are in the 90s. Even ocean water is in the 80s.
One of the best tech channels I have seen on KZhead. Thank you for your time and effort!
*Congratulations, you made a feezer that needs an outdoor radiator, only works in winter, and still uses way more power than a commercial one!*
Your dedication to this is staggering. I love your content, and always walk away with more knowledge and questions than I came with. Thank you much!
All quality, all the time.
I'm inspired to build a little mini fridge for use in the bedroom. Thanks for another excellent video!
This channel is honestly therapeutic. Everything is explained so incredibly well and precisely.
Thank you!
Thank You for posting this amazing videos 👍
Much Respect for this Man!
I used to run my custom radiator for my desktop outside my window. I slapped on 8 of those Delta fans on it and if you told me I could've cooled a small car engine, I'd have believed you. And the nice part about those fans was that if you did accidentally stick a finger in there, it'd cut it smooth off. Much easier to attach when you got to the emergency room. Michigan winters get down pretty low, so most of the year I didn't even need to run the fans. I didn't want to run any antifreeze thru the loop, so I just left the computer on 24/7 to prevent freezing. I'm sure my parents didn't care for that when they got the electric bill. During the summer, the considerable heat load was dumped totally outside, so I figured the decreased load for the house's AC made up for it. And those fans sounded like a jet engine, so the noise was also kept out of the house. I found out that every kind of bug and leaf will get into that radiator. I even doubled up on filters and created a hood to try to protect the fans from rain and falling debris. Anyway, one winter the polar vortex came with it's -20 degree air, and along with my humidifier for the dry indoor air, condensation formed everywhere inside my case and shorted everything out. Probably should've packed the CPU socket with dielectric grease, but I don't think it would've mattered.
Thanks for the video. I love the simple ways of explaining things. JP
why do i sit here at 3am waching water freeze....
this is the 3am sickness!!
2:59AM and I’m reading this comment 🤣
bunnlose The simple answer is because it is better than watching 'paint' dry. Watching water freeze is crystal clear. N'ice
very inspirational!!! I am so glad you are doing this. I feel this is almost taboo territory when it comes to "traditional" Cooling methods ... :)
Keep em coming! These videos are a gift to humankind! Thank you for sharing your knowledge and expertise!
Great demo of peltier devices. Can heat with them too.
Thank you. This channel goes to 1million subscribers by the end of 2019
Evaporative air conditioning? This I gotta see. Subbed for sure. Can't wait.
If you ever visit New Mexico you'll see all the swamp cooler (evaporative coolers) to your hearts content. That's all we basically use out here. Metal box, will it with water, simple pump to pour it over aspen straw pads, 1/3hp motor to spin a giant squirrel cage.....bamm...you got evaporative cooling. Sucks during humid season though (august)....but I can run the cooler 24/7 for about $100 a month.
I really do appreciate this channel.
I enjoy how you build something, say you can do better, and then come and make a video where you build another better one.
Thanks!
I hope that you're also going to evaluate using a Sterling engine as a heat pump. It should be significantly more efficient.
Whatever you do , please don't change your intro music. I love this channel man
Yes, it is such a pleasure to listen to. I very much prefer something like that over the styles a lot of others go to. It is background - it should be easy listening. They did a great job on that pick! 🙂
Another great vid. I like that it’s a mix of shorter and longer videos. Sometimes I want the hour+ build, others I just want a quick vid to pass a little time.
There is so much that is beyond me in these videos but never the less it is all fascinating.
man. i had this idea some time ago. its nice to see how it work! thanks for your video. now i can prove my wife that i am not crazy😂
Cooling performance indoor.....220w continuous START: 16:18hrs @ 15.2 Celsius STOP: 17:16hrs @ 0.0 Celsius Summary: Roughly 1hr of 220w continuous to drop temperature from 15.2c/60f to 0c/32f
@Warrior Son A chest freezer has more thermal mass that is already at its terminal low temp and that is an aid in freezing things put inside. For what it's worth I picked the first chest freezer I could find (Frigidaire FFFC09M1RW) and its estimated annual kWH was 218, so that's an average power draw of 24W over a year. It does appear that the TEC is substantially less efficient, not even counting the much larger volume of the chest freezer (~279 liters).
Excited to find this series. I am curious about designing a solar powered, small scale, ice machine.
This is insanely relevant to me, thanks Tech Ingredients. I have been trying to find a good way to cool electrical device enclosures in the Texas heat in the summer by using TECs, potentially with solar power (while keeping the enclosure water tight). This freezer is about the same size as the electrical boxes I will be using, so its awesome to see a video that shows they can be effective, even if I have to use several of them.
I hope you're going to dip the boards in some hydrophobic at the very least in Texas humidity.
Living in a cold country, I would love to see an comparison between solar cells vs a TEC or Stirling wall electricity production. How much energy can be recollected vs the cost? Edit: Same would probably be interesting in warm countries, I guess.
yea, we all wanna buy these in a shop. Producing electricity or being flat. However TEC still consumes 3times more energy than coolant systems. 219 Watts is not couple of Watts as he says. They need to suck out billions in the process before it's common - just like with LED lights. We needed to pay for the CLF factories first and then pay hundreds for LED. At least Chinese are "fixing" the crooked market LOL
Can you make a desk top drink cooler/warmer? That would be EPIC!
I think he already did once. Try to search it up.
@@dizzolve Right on ill look. Thanks.
In the old days, they had a tin box that was outdoors (through the wall) with an insulated door indoors... (no light)... (other than the cost of materials and maintenance) free refrigeration / freezing...
Thank you for posting such intelligent, inspiring and well produced content! I've been interested in finding DIY low voltage refrigeration solutions for a sailboat. After stumbling upon TEC chips online, I immediately got excited thinking about their potential uses. I'm even more excited to see that you have 3 videos covering pretty much everything I wanted to know about them! Thank you again. :)
Sure, glad you took the time to watch!
On a sailboat you have an easy time with the cooling side. :)
8:03 "And you can hear how loud it is"... actually, not really XD
I have a spare FLIR one. I can give you the thermal camera if you want. ❤️
Don't those cost a fortune?? Good on you for offering to help this channel and all the educational material they produce for so many. Cheers!
Lank Asif i have one private for me and one of the work that I don’t really need. These devices are not that expensive... around 300€/$. For this channels it’s absolutely worth it to give it away! FYI, it’s the second version of the FLIR one (with the lightning port). And these are pretty cheap these days. ❤️
@@gulsten You are too humble. Many people would consider a donation of $300 or 300 Euro as an unbelievably altruistic act. I hope your offer is accepted and your good will helps others. Even reading your effort to contribute to others has inspired me to "pay it forward" and do something for some stranger tomorrow. Consider this a reward ;) You seem like someone who will appreciate this gesture. I wish you the very best.
Lank Asif thank you very much kind stranger! I hope that my offer will be accepted. Because I don’t need two similar thermal imaging cameras and this channel deserves it! It is like I’m tinkering with my dad... but this dad is over the Atlantic Ocean and has a huge knowledge about the things he is doing! And this deserves a Little „Gift“ from bis „European son“.
Well, now we're friends. Please contact me if you ever visit South Africa. And it wouldn't matter if you had 50 of those FLIRs, you have one that you're happy to donate to helping educate others. Even if your offer isn't accepted, you're an example to others on how a person can contribute in general. Ultimately, I reckon it's not about what you manage to put into helping, but what you're willing to give. Take care, friend.
Hi, you're right about the supercooling. I work in pharma and the freezing exotherm is a common observation in lyophilization (freeze drying) cycles. Pure water likes to freeze at -5C to -10C, and the release of heat from freezing brings the temp up to 0C during the phase change. Great video thanks
Thanks for the feedback!
@@TechIngredients Thanks for the great content!
This is really interesting material. I appreciate the effort you put into providing it. Many thanks!
How about a TEC based water still that utilizes both the hot and cold sides of the unit?
thats a neat idea
You need a controller to maintain stable temperature.Then test how much power it consume in 24 hours.
Exactly. IDGAF how much current it draws at a given moment, but how many kW/h/year!
@@fun_ghoul If you ran it constantly, that is without a temperature shut off (which this is a proof of concept and doesn't have one) . So lets take this one as an example. I believe he said it uses around 240w (P = I x E) that would be an hourly consumption. There are 24 hours in the day which gives us 5760w (5.76KW/day) you can then calculate your wattage on a monthly basis (172.8KW/h) and from there see how many KW this burns a year (2.074Mw/yr) and in the US on average it would cost approximately $352.58/yr to operate. Now if you go with the fairly "typical" duty cycle on a freezer and fridge is around 8 hours (1/3 of the time) you could of course improve this with your choice of insulation. I'll leave you to figure that usage out yourself, you're a big boy.
@@AcydDrop 5760Wh, not 5760W, and definitely not 5760w. Watt is a unit of power, power x time, as in watts x hours, or Wh, is amount of energy. 240W constant during 24 hours is 5.76kWh, that number is correct. 5.76 times 365 is over 2100kWh, or over 2.1MWh. The symbol for watts is W, the symbol for kilo is k, lower case. Apart from that, you're mostly spot on. This being proof of concept, and actual energy consumption over a full year is irrelevant. Singe step TEC systems are immensely ineffecient heatpumps against large temperature differences, most of the energy in this system was wasted just compensating for heat conducting back through the TEC modules.
@@fishyerik You do realize what I said, and what you said is exactly the same, right? 5760Wh = 5.76kWh (5750/1000 = 5.76kWh). But I was confused since a watt has nothing to do with time. It's a function of work performed as represented by P = I x E (P = watts, I = Current and E = volts). For example at 9:04 mark you can see it's drawing 11.4 Amps at 17.6 volts. So P = 11.4 x 17.6 which gives up 200.64W for example.
@@AcydDrop My comment wasn't confusing at all, you were confused to begin with when you either thought that watt is a unit for BOTH power AND energy, or you thought that power and energy is the same thing, I don't know which of those is worse. Watt is the RATE of work performed, NOT the AMOUNT of work performed, as rate is called power, amount is called energy. 1W is power, 1W for 1 hour is energy, you can write it 1W ⋅ h or, as usual, let the dot be implied, and write it: 1Wh. 1W/h is used to describe CHANGE of POWER. Not absolute power, not energy. So, no, neither 5760W or 5.76kW/day is the same thing as 5760Wh or 5.76kWh, absolutely not, the differences are FUNDAMENTAL By the way, the symbol for volt is V, not E, E is usually energy.
I took notice of the cost drop of the peltier devices. Looks like I will be buying some now! Again, fantastic and ULTRA interesting!
You're right. We built a large thermoelectric generator because these have become so inexpensive. We'll be taking that... primitive.
Nice Video Work and Excellent Story too. You are at the top.
Please drop the logo overlay on the fast forward...
Maybe it's because of people stealing the video? Happens a lot, especially KZhead->Facebook
MrSnowman is probably right, TKOR has started flashing in his logo one or two frames at a time at random points to discourage IP theft.
The logo is a practical necessity until people stop stealing valour for social profit.
@@wtechboy18 iP tHeFt
@@wtechboy18 They do that for competitions...to try to make up for the plummeting quality of their content
Music is nice ... The light show is a bit distracting tho ...
Yes a bit too long
I like this, I live in Finland, country with long winters. We use nature as cooling a lot, but the problem is temperature differences during fal- and springtime. This was beautiful really. Thank you.
You're welcome.
if i'd had a science teacher like you as a kid, how different the past decades might have been impacted. appreciate your work!
Thanks!
Please remove ALL music when ANYONE is talking
Great explanation and insights into heat transfer and design consideration. All your videos are exceptional.
Thanks!
I've been playing with lithium bromide cooling for years. Can't wait!!!
We got the best results with lithium chloride. But, the cheeper and less toxic calcium chloride still produces twice the cooling effeciency of a conventional air conditioner.
@@TechIngredients I got libr on eBay but only enough for small tests. Scaling up with cacl is a lot more practical.
Tx! Just my 2cents TEC1 12710 TEC1 means 1 layer TEC1 127 = number of junctions/cells/elements TEC1 127 10 max amperage. So if you are going to drive the elements ‘gently’ then you can use the TEC1 12705 or 12706 which cost about half of the 12710’s.
Is it something like CPU's, where they make all in the same batch, then sort them by max(whatever)?
Anders Doverud I’m sorry but I’ve no idea. I just read the specs.
I want one of these for under my desk at work, perfect for a stash of caffeinated beverage of choice
Here you go... Cooluli Classic 4-liter Compact Cooler/Warmer Mini Fridge for Cars, Road Trips, Homes, Offices and Dorms (Black) www.amazon.com/dp/B0771S9XT8/ref=cm_sw_r_cp_apa_i_UKHUCb84SFGN5
@@videoviewer2008 yeah except they wont ship to Australia, and the rates from USA->Aus are extortionate at the best of times. Also the TechIngredients model is way cooler :D
When an engineer retires.... these videos rock! Thx for your videos!
Sure, thanks.
good timing I was gonna name a small version now I'll wait for the desiccant version.
Sounds like some good upcoming videos. Good engineering testing. That's the correct way to do things. I made a TEC back in 2007. Single unit on the refrigerator cost me USD$25 at the time. My design aspirations was to keep a single coke cold at about 4 degrees. Note this was supposed to be a cold coke that I was just maintaining the temp for consumption over the day. Surprisingly I was able to get ice when it was operated in a conditioned room at about 24 or 25 degrees (I live in the tropics). It was an open unit so I did a condensate line. Turned out that I needed to keep that elevated and put in water since the conduction to the actual coke was too low without a little water at the bottom. That's how the ice formed. At the time I recall I used about 40W of power so I was really not amused when devices off the USB drive that at the time had a 5V and 500nA spec claimed to be able to cool a drink. I am putting a link to the video I did relatively recently just in case anyone wants to replicate. Its not that hard of a build and the form factor is useful for drinks. kzhead.info/sun/n7yqldtvpJuorIk/bejne.html
I am amazed of the knowledge this guy possesses just wow
4:20 "What were going to do today... is demonstrate the cooling properties, as we freeze some ice" 🤣🤣🤣 Sorry, that one got me. Like when people say they're going to toast some toast... LoL! On the serious side of things, another great video, filled with good information. Thank you! Keep up the awesome, inspiring work!
I keep tracking the amount of subscribers you guys have and I can't understand why don't you have millions. This channel is awesome! Thanks for the content and quality! Keep up the good work!
Thanks! We suspect that because we began to expand a little over one year ago, we are growing in a far more competitive environment than many of the already large science and technology channels. A little help from KZhead would be appreciated.
You're a good guy. Thanks for the exceptional videos.
What's crazy is I have a refrigerator/freezer in my garage that belonged to my grandparents that they bought in the early 1930's, a G.E. Monitor Top model CA, and it uses less power than this when running the compressor. It's almost 90 years old and the only thing thats been done to it was I replaced the electrical wiring becuase it had become very brittle, and i gave it a nice new epoxy white paintjob. If only they made appliances with such high build quality today.
Now I want to build a chest freezer for my school bus RV project using Peltier tiles
Awesome! I look forward to the desiccant version! One of the ideas I kicked around for my cold box is using a compressor cycle freezer and pumping either ethanol or propylene glycol solution through. I eventually went with TECs because even though it's much less efficient overall it's just a simpler design and I can hold the temperature within like a tenth of a degree. :D
Loved the content, technical details and the explanation. You are an awesome teacher too. One request: can you add some details of the external heat sink? The considerations and construction (including the connection to the freezer). Thanks again!