Reasons why you CANNOT use Peltier for air conditioning

Summary

In a detailed exploration, Curious Scientist explains why Peltier devices are not suitable for creating efficient air conditioning systems. The video delves into the performance curves of thermoelectric coolers, showing that while they can achieve low cold side temperatures, they lack the requisite power to cool a room effectively. The Creator demonstrates how the power consumption versus the cooling output of these devices makes them impractical compared to conventional AC units, which are more cost-effective and efficient. He advises against using Peltier devices for air conditioning purposes due to the high cost, complexity, and limited effectiveness.

Highlights

• Peltier devices can't cool effectively despite achieving low temperatures 🚫
• The performance curve study reveals why Peltier devices are inefficient for AC 📉
• Real-world math shows that traditional AC units are more practical and affordable 💰
• The video debunks myths about homemade Peltier AC systems 👫
• Creator provides insightful physics lessons on heat transfer and energy efficiency 👨‍🔬

Key Takeaways

• Peltier devices achieve low temperatures but lack cooling power for effective AC 🌡️
• Performance curves reveal major inefficiencies in Peltier implementations ❌
• Traditional AC units offer better efficiency and cost-effectiveness 🚀
• Building a Peltier-based AC is costlier than buying a standard unit 💸
• Complex setup and calculations outweigh any potential benefits of Peltier AC 🛠️

Overview

Ever thought about DIY-ing your own air conditioner with Peltier devices? Well, Curious Scientist is here to tell you why that might not be the best idea. In this eye-opening video, he breaks down the science of thermoelectric coolers, and they're not quite what they seem! Sure, they can hit impressively chilly temperatures, but when it comes to actually cooling down a room, these devices fall short. 🌡️❄️

Curious Scientist takes us on a journey through the nuts and bolts of Peltier devices. These aren't your average gadgets; reading performance curves becomes crucial, and boy, do these curves tell a story! The device can churn out low temperatures but lacks the oomph in cooling power compared to our trusty traditional air conditioners. Why spend more for less power? This vid dives deep into why standard ACs get the job done better and cheaper. 🌬️

And before you run off to tinker with some thermoelectric coolers hoping for a cool breeze, here's the kicker: creating a Peltier-based AC could break the bank! With high power demands and the complexity of setting up a functioning system, Curious Scientist urges you to save your resources. Let the experts handle the cooling — and let’s leave Peltier modules for the mini fridge art hacks instead! 🧊🍹

Chapters

• 00:00 - 01:00: Introduction and Overview In the introductory chapter, the presenter aims to demonstrate why it is not feasible to create a reasonable air conditioner using common advice and a Peltier device thermoelectric cooler. The chapter outlines a plan to examine the datasheet of such a device and perform basic mathematical calculations, emphasizing that simple math and common sense reveal the impracticality of constructing an effective air conditioner in this manner.
• 01:00 - 05:00: Understanding Performance Curves This chapter focuses on understanding performance curves, specifically in relation to air conditioning units, although the principles can be applied broadly. It begins by addressing a common misconception where people upload videos claiming certain structures are air conditioners based on their appearance, despite not functioning as such. The chapter then explains how to correctly interpret performance curves. These curves provide vital information about how a device performs under different temperature gradients, which is critical for assessing its true functionality as an air conditioning unit.
• 05:00 - 09:30: Discussion on Temperature Differences and Cooling Power The chapter discusses the relationship between temperature differences and cooling power in certain devices. It emphasizes the power capacity of devices based on the temperature difference between the hot side and the cooler side. Specifically, it mentions a curve defined for a 50 degrees Celsius hot side as an optimistic estimation. In practice, temperatures often reach around 1450 degrees. The example given is of a 15 ampere Tec 12 715 unit operating at maximum load.
• 09:30 - 13:00: Cost and Feasibility Analysis The chapter titled 'Cost and Feasibility Analysis' begins with a discussion about the performance capabilities of a device, particularly focusing on its ability to handle 15 amperes of current. The speaker recommends viewers to watch previous videos for more detailed explanations on the cooling capabilities of the devices and various measurement methods. This chapter specifically emphasizes the theoretical aspects behind performance and capability assessments.
• 13:00 - 15:00: Concluding Thoughts and Recommendations The chapter delves into the technical aspects of a certain topic, discussing variables such as the DT on the x-axis, which represents temperature in relation to the hot side temperature. The content suggests a focus on technical investigation and analysis involving these variables.
• 15:00 - 17:00: Summary and Farewell In the chapter 'Summary and Farewell', the speaker explains how to calculate the cold side temperature by combining the delta T with the hot side temperature. By subtracting the delta T from the hot side temperature, the cold side temperature in Celsius is determined. The explanation concludes at the point where the temperature difference is 0 degrees.

Reasons why you CANNOT use Peltier for air conditioning Transcription

• 00:00 - 00:30 welcome everyone in this video I will try to convince you about the fact that you cannot be on a reasonable a CE by using party advices and I will go to the datasheet of certain Peltier device thermoelectric cooler and then we will do some very easy math just to prove you just based on the math and simple common sense that you cannot really really build a reasonable air conditioner so a lot of people tries to do that and a lot
• 00:30 - 01:00 of people are uploading videos about some structures or some kind of things that they call AC but I'm pretty sure that they don't work as air conditioner so first of all let's learn how to read these performance curves so these performance curves will basically tell you that at a certain temperature gradient so temperature difference
• 01:00 - 01:30 between the hot side and the courtside how much power you can basically pump with these devices so if you take a look at this curve this curve is defined for 50 degrees Celsius hot side and this is like optimistic estimation because usually you have it around 1450 degrees if you have let's say this 15 ampere Tec 12 715 unit running on its maximum load
• 01:30 - 02:00 or maximum performance which I mean that 15 ampere is running through the device so if you haven't checked my previous videos I strongly suggest you to do that because I explain a lot of things about the cooling capabilities of these devices and I also talk about some different measurement methods but here it's more about the theory behind it or
• 02:00 - 02:30 more like the investigation of the different technical stuff so what you can read from this chart is that you see the DT here on the x-axis so that is basically the temperature compared to the hot side temperature so what this means is that if you have now just let's write down the variables so we have the hot side and then we also
• 02:30 - 03:00 have the delta T and how we get the cold side temperature is basically we just combine these two so that means that we just take the hot side temperature and we subtract the delta T from that and that will give us the cold side temperature in in Celsius of course here so I just write down the number so here which is at 0 degrees difference so
• 03:00 - 03:30 the hot side and the cold side are at the same temperature this means that the TC is also at 50 degrees here we are at 40 degrees and 30 20 10 and then 0 so now we are reaching some lower values and minus 10 degrees minus 20 degrees and minus 30 so I think this is like
• 03:30 - 04:00 quite understandable and then you see on the y-axis that the cooling power is defined in watts that is not the same power as the device is using when you connect it to the power supply this is the cooling performance that it can provide you so let's see what happens on this curve first of all let's check this usually most of the videos and I also
• 04:00 - 04:30 have some of those videos they say and they show that they can reach minus 40 minus 50 degrees with single or stag-party units and they are very happy about it and I was also happy this is a nice thing but then you have to consider that if you are somewhere here in this curve let's say you are in this in this corner here if you go and draw a line then you are
• 04:30 - 05:00 basically at like I don't even know ten or even less watts of cooling power so of course you can reach very low temperatures so you can have very high DT or delta T values but then you may not be able to cool anything and that's just what happens so basically when you run your empty Tatia device and you are able to cool the hot side enough that
• 05:00 - 05:30 your hot side temperature instead of this is let's say twenty degrees then if you take these Delta T's let's say the delta T equals 80 just to let's say overestimate everything then you should be able to go down to minus sixty but then you have different effects and you have the heat loss to the environment basically and so on so you end up somewhere around minus forty let's say
• 05:30 - 06:00 but then you are not able to transfer heat at all so that's what you have it in this corner and this this you really have to process this or digest distance if you can reach very cold temperatures on the hots on the cold side of the patch in unit that does not mean that you can cool down anything with to that temperature or that you can cool down anything to any temperature at all because basically if you can have this
• 06:00 - 06:30 very very low temperature that means that your QC is very low so you are basically just balancing out the heat which is like escaping to your cold side from the from the environment because you haven't surrounded your particular with proper insulation and so on and so on so this is not the case if we want to do something more which makes a bit more sense then we can do
• 06:30 - 07:00 the following so have you read this chart is let's say we want to produce 30 degrees delta T so that's nice and cold delta T equals 30 sorry degree Celsius so that means in our case that the TC should be of course 50 degrees Celsius minus 30 degree Celsius so that's 20 degrees Celsius so this means that your cold side will be 20
• 07:00 - 07:30 degrees but let's check what happens so here you draw a vertical line and then you see that these curves intersect these other curves which are defined for different currents so you do another now horizontal line so you basically go and cut the y-axis and now let me write down just these numbers for the currents so we have three amperes we have six and of
• 07:30 - 08:00 course nine 12 amperes and 15 amperes so the way you read this curve is the following you pick a delta T based on your requirements of the cold side temperature in my case I want 20 degrees and that means that the delta T is 30 degrees if my hot side is assumed to be
• 08:00 - 08:30 50 degrees Celsius so you draw this vertical line along the line of the 30 degrees and then you draw the horizontal lines that the vertical line crosses these different curves for the different currents and then you read their the verticals or the horizontal line meets the y axis which is the QC so the first let's say that's around
• 08:30 - 09:00 right so this will be the current and this will be the QC so I just try to draw columns and like this so this is let's say six watts so then this is nothing so we can see that even though we don't have that high delta T then at 3 amperes which is of course just 20% of
• 09:00 - 09:30 the performance of this device it cannot really do anything so that's six Watts that's not enough to not even enough to cool down a large bottle of water then we move up to six amperes so we double the amperes and then now we have something more reasonable let's say this is 45 what and then we go up again by 50% so these are basically from here to
• 09:30 - 10:00 here it's 50% step 150 then at nine amperes we have now 70 watts so this is like a strong light bulb or nowadays I don't know if you can buy this because everyone is buying LED but in the old times it was possible 12 amperes so we are let's say 85 or 85 ish that's a bit lower maybe or higher and then let's say
• 10:00 - 10:30 let's round it up to hundred so let me highlight this so if you run the maximum current through this device and you are able to keep the hot side temperature at 50 degrees and your desired cold side temperature is 20 degree Celsius therefore your delta T is 30 then you are able to pump 100 watts of power with
• 10:30 - 11:00 your fatiah device but now comes the fun fact this is just the heat that you can pump out and what you have to consider that you have your patio device let's say this is the hot side then your device looks something like this so in between the hot and the cold side of course you have the basically the semiconductors so
• 11:00 - 11:30 let me write it down semiconductors so what happens here is if I magnify this and bit simplify so you have this let's say heat reservoir which is the cold and then you have a pump which is basically the set of a set of semiconductors and then you
• 11:30 - 12:00 have the hot side so what happens here is that you pump the heat from the cold side to the hot side by running large amount of power to your semiconductors so here the QC is in the way but here you also put in work so basically what happens here is that you have to consider that you run this device at 15 amperes and that HAP that happens
• 12:00 - 12:30 roughly at 15 volts or maybe 16 but let's so we now know that P equals I times u so this is 225 so you basically generate 225 watts of power which appears on your hot side and this is just one unit which appears on your hot side and you have to get rid of this so just think about the traditional
• 12:30 - 13:00 AC systems so you have this huge external unit there they basically based the condenser and it's a very loud huge box and that's where you get rid of the huge heat which was like carried out from your room so now you have 225 watts for one unit and for that you can only pump out hundred watts so that's I just did some Google search and one thing
• 13:00 - 13:30 which immediately came up an AC unit which can cool a room with 28 square meters of floor area and the cooling power of this not the power that it takes from the outlet but the cooling power was 202 thousand watts and then this unit has 100 watts so we need let's
• 13:30 - 14:00 write a shopping list so one device is hundred watts and we need 2,000 watts that means that we need to 20 devices right what does that mean is each device roughly if you buy it from China five US dollars so five times twenty hundred dollars okay this starts to get expensive but that's not the expensive part see
• 14:00 - 14:30 this number and this number each device you add you have to add 225 watts so I just checked these independent units which you can buy for for example LED strips so I checked 24 what power supply sorry 24 volt and 20 ampere power supply and this is roughly $30 per each unit
• 14:30 - 15:00 and I say that okay we might say that we sacrifice a little bit of power but we don't consider the different numbers we still say that okay hundred watts but instead of buying twenty of this to provide more power to this then we should we just buy ten units so each of this power supply will provide power for two units so we don't waste that much
• 15:00 - 15:30 money but then this is already $300 so now we have our patio coolers and we have our power supply for it or power supplies and we are already at $400 and let's come back to this part here we have 20 units right so 20 units and
• 15:30 - 16:00 each unit if you check the surface area of it is 40 by 40 millimeters so you can make a grid of this let's say you can place them nicely close together but you cannot because of the cables so you can place them more like a rectangle and rather rather a rectangle damask square because these devices are something like this so you cannot put more than three
• 16:00 - 16:30 more than two next to each other nicely so you cannot have let's say a four by four row of them because the middle units will have problems with the cable or you can drill through the heatsink but that's too bad but let's say now we don't care about the cables because we are just curious about the surface area but this basically creates let's say a four by five unit so that means that in one direction you put down four units
• 16:30 - 17:00 and the other direction you put five and then that's how you make up the twenty units so I just try to draw nice Nihon two three four five and one two three four so something like this and this is your twenty device and then the shorter side will be sixteen centimeter and the longer side will be twenty centimeters so that's a quite big area and then you
• 17:00 - 17:30 have to remove the heat from the hot side from this big area and you will probably need either water cooling or something and you have to remember that you have to remove the heat out from your room because if you keep the cooling at the same room then you just you warm it up but you don't cool it so that most probably you will end up with water cooling so the water cooling is quite expensive you can maybe use some cars water queen but that doesn't make
• 17:30 - 18:00 sense too much and maybe you will have a you need to build a customized heat exchange plate that you can fix this and then you have the other side of the particular so this is let's say this is the cold side and that has to be in connection with your room somehow and of course you need some let's say heat sink and then you always need some fans to move the air because
• 18:00 - 18:30 otherwise if you cannot move the air to the fan through the heat sink sorry then of course you are not able to cool down the air in your room so I would say that roughly $600 or maybe more you will end up with that to build Apache based device which can work some but as an air conditioner and can provide some cool
• 18:30 - 19:00 air but I'm pretty sure that the outlet temperature of the ACS the proper ACS are are much lower or at least significantly lower than 20 degrees so then we might need let's say 40 degrees difference of temperature so if you just quickly look at the this curve then you see that then you are you you cannot
• 19:00 - 19:30 even run your device it's reimburse and then this becomes something like I don't know 28 and then this becomes something like let's say 50 52 and this now this becomes so you go from 9 to 12 and person you stuck at 70 what and then you go to 15 and you are somewhere around
• 19:30 - 20:00 not even 80 maybe what so you lost a lot of cooling power so if you really want to cool and what I mean is you are really able to remove heat because cooling is not maybe it's a wrong phrasing but cooling is not about decreasing the temperature in a sense that you just get a smaller number but you have to remove the heat from a system so and that's that's a lot of
• 20:00 - 20:30 work so of course if you remove the heat you decrease the temperature of the unit let's say you don't have phase transformation like you freeze the water because then that's a different story but if you think about the air and you just want to cool down the several cubic meters of air in your room that's purely just pumping out the heat and as you pump out the heat you you will be able
• 20:30 - 21:00 to decrease the average kinetic energy of the air molecules and that's basically their temperature so then they have a cool-down and you will feel that the air is cold but you can see that that this is not as simple as you would think so don't be too confident by being able to reach let's say minus 20 degrees on the surface of your unloaded particular because you will not be able to make it
• 21:00 - 21:30 into a proper AC device and you can see that one device which is hundred watts is just perfectly not enough to provide cooling for your room and just imagine that you have tremendous losses to the wall by opening your window and you are also as a human heat source so and also you have your
• 21:30 - 22:00 devices inside your room maybe you can cook in the room where you want to have the AC and so on and so on so that this will not really work so let's check the price of an AC unit which is capable of doing this 2,000 watts so this unit which I checked this 28 square meter it's a portable unit but of course it
• 22:00 - 22:30 has its exhaust to both sides so you can push the cold air into your room and then you have to get rid of your let's say create it heat somewhere so this device which is 428 square meters and again 2,000 watts of cooling power costs around three hundred dollars and then three hundred dollars can buy you a
• 22:30 - 23:00 device that you just plug in into your outlet let it run and it does everything for you probably it takes up much less space and probably creates less headache than building this device I'm pretty sure that maybe you can short some circuits or do some chipping of these very delicate fatiah units you can easily break of the
• 23:00 - 23:30 ceramic plates especially their corners so this will not work so please believe me that based on these numbers and this is really just a hand waving calculation but it is basically this what you need to calculate you cannot do this way so you cannot be add AC cooler so all those videos you see no ask them please to show you the numbers show you let them
• 23:30 - 24:00 show you how long did it take to cool down their room what was the temperature of the room that did they put the heat how much it cost regarding the electricity bill and so on and so on and at the end of the day you will see that when you do the math and you do the calculations and you see these are very very simple calculations and you can do it very easily just multiplication and basically that's all and some common sense that you really
• 24:00 - 24:30 cannot do this so just don't don't try it because you can buy a brand new nice safe device which can do the job for you for fraction of the price so yeah I hope that this did not sound is some sort of raging or something but I just really want to show and tell the people that just don't try because yes it's a very
• 24:30 - 25:00 nice experiment but you will waste your resources and time on something that you might not be able to use so if you just want to make some experimental stuff I don't know cooling down a cup of water or or doing something like that or building a miniature fridge that can work that can nicely work you can see some products which are based on patio devices and these are let's say
• 25:00 - 25:30 miniature fridges or something which should keep the temperature set very not very but it's like a cool cool temperatures so not even cold but it's like let's see 14 degrees Celsius or something that can work but still it would require a lot of work to remove the heat from the hot side and keep everything tightly sealed and so on and so on so regardless of these
• 25:30 - 26:00 informations that might disappoint you if you wanted to build a similar based on a patio device I hope that this video was useful and it was somewhat informative and now I hope that you can learn how to read these performance curves or performance charts for the patio coolers and you can look up these data sheets from Google easily so I hope
• 26:00 - 26:30 that this was useful for you and see you in the next video