Peltier Cooling Chips for fermentation control or ...

[KCBrewer]

My BIL showed me this site UnitedNuclear.com and I found these Peltier Cooling Chips to be pretty intriguing. There is a smaller one for $19 too. I may pick up one of each size and see how they work for fermentation temp control mounted to the side of a fermenter. It seems like there could be a multitude of uses for them, but I'd like to pick some up to see how well they really work.

Another cool thing about them is if you apply heat to one side, they generate electricity, so even more possibilities.

They also sell erlenmeyer flasks and crazy strong magnets, some that are strong enough to break bones if not handled carefully, but the smaller ones would be great for making a stir plate.

I know there are some pretty technical people on here who could think of other creative ways to use these in a brewing aspect, and the prices seem reasonable.

I'd really like to hear from anybody that has used these before, in any aspect, and can comment on whether the cooling capacity would be sufficient for fermentation control or maybe cooling a small chamber or draft tower.

 

[remilard]

As far as I know B3 is the only example of successfully cooling by mounting a peltier to a fermentor.

Several people on here have tried it, not much success that I have seen.

 

[chemman14]

As far as I know B3 is the only example of successfully cooling by mounting a peltier to a fermentor.

Several people on here have tried it, not much success that I have seen.

so that is how their self contained fermenter thing works!

 

[CoalCracker]

Peltiers are very inefficient. That would have to be a pretty good design to be worthwile

 

[KCBrewer]

Yeah, I read Yuri's thread and his attempt at using them and decided to forget about it. I should have known someone on here had already attempted it.

 

[RiverCityBrewer]

I think the hardest part would be getting the flat peltier to connect to a rounded surface and still get decent conductivity and efficiency.

 

[remilard]

I think the hardest part would be getting the flat peltier to connect to a rounded surface and still get decent conductivity and efficiency.

Yep. That's why a heated and cooled B3 conical costs around $1000 more than the non heated and cooled one. You have about $200 in a temp controller and insulation and a fermwrap, the rest is mounting the peltiers which they claim is extremely labor and equipment intensive.

Makes an upright freezer look awful appealing unless you really want some bling factor or a square foot or so is a make it or break it for you.

Several homebrewers have wound copper tubing around a purchased conical and pumped glycol through it. More efficient than a peltier and probably more DIY friendly.

 

[passedpawn]

I've got a big peltier element with fans on both the cold and hot sides. I'm sure this sucker can chill a fermenter.

I've also designed a control board to monitor temps (thermocouples) and control the element. I hope to make some assumptions of the amount of energy created during fermentation. More after the holidays.

 

[chemman14]

I've got a big peltier element with fans on both the cold and hot sides. I'm sure this sucker can chill a fermenter.

I've also designed a control board to monitor temps (thermocouples) and control the element. I hope to make some assumptions of the amount of energy created during fermentation. More after the holidays.

should be interesting to see your results

 

[DeBrewer]

passedpawn -
Any update? I have been reading about peltier elements and like most am intrigued by the possibilities. I am building a large stir plate to hold up to four 2000ml flasks and in doing this I need temp control. I first intended to use a water bath with fish tank heaters but that became rather convoluted/expensive to control individually.

I am thinking a water bath with a few peltier elements to heat/cool. The stir plates(fans) will already need a DC source so there should be a source to run the plates already. It is early in the design stage but makes sense in my head...

I have some ideas for implementing them on a larger scale but am unsure as to efficiency. Everything states they are inefficient but in all reality how do they match up to the same premise of a heating/cooling setup like heated coil/compressed chilling(refrigerator) or heated/chilled glycol.... I know that is a broad generalization and there are many factors, but for my hypothetical brewery maintaining a boiler and glycol chiller seems fairly extensive whereas a jacketed conical with an array of plates would be fairly straightforward.

Lets explore just the cooling side. In it's simplest form given a control of 5 cubic feet of air at a starting ambient temp of 70F and the same amount of energy provided and the same price point given; which one cools the air space faster to lets say 50F. I know it is very hypothetical but it is a comparison that should be indicative for our applications. I think it would be best to have your controls in place and then base your available energy off of the compressed units consumption and tailor your plates to match. So to compare you would need to match an AC to DC converter(rectifier) to the consumption of the cooling unit and then add on however many peltier plates would be needed to consume its output but still comparable in price. This comparison will give you efficiency based solely on time which still may be skewed. This is possible since you could buy a cheaper rectifier(lower consumption) and more plates and still be in the same price point and consume less energy but cool more.....So truly you need to have your controls and base the comparison off of time and consumption.

Another caveat is that a peltier can cool in the jacket itself whereas the glycol would need a pump....

There are sooo many different scenarios but I have yet to see anyone prove it. I have read through some calculations on their efficiency but truthfully they make my head hurt... I want to better understand their inefficiency in application. The thought of a fermenter that is autonomous to everything and could be maintained from a battery under power failure seems sweet but if I have missed the boat on how inefficient they actually are then please show me the light.

EDIT: I really think there is no definitive answer in that there will be a curve for each system to where peltier would be more efficient in small areas and a traditional compressed system will be more efficient in larger. Considering that the peltier method is not used in large applications(to my knowledge), someone much smarter than me has already proved this...

 

[Catt22]

clipped from Wiki:

"Thermoelectric junctions are generally only around 5–10% as efficient as the ideal refrigerator (Carnot cycle), compared with 40–60% achieved by conventional compression cycle systems (reverse Rankine systems using compression/expansion). Due to the relatively low efficiency, thermoelectric cooling is generally only used in environments where the solid state nature (no moving parts, maintenance-free) outweighs pure efficiency."[edit] Us

http://en.wikipedia.org/wiki/Thermoelectric_cooling

 

[passedpawn]

Yea, they take a ton of power, and the hot side of the junction throws all that power as heat.

I've still got the chillers, and I think about doing something with them all the time.

 

[lgoolsby]

My wife got me a USB soda can cooler that used a TEC plate to chill. I had a problem with using it around my computer because condensation would pour off the thing and run all over the desk. Not very conducive to keeping a working computer. And that was only with 5 volts from USB so if you cranked it 12 volts... They diffinately chill but like others have said are not very efficient.

If you had a stainless conical you were fermenting with that you could maybe glue a couple to the side and run it through a controller. That could maybe keep temps down. You could even flip a couple around so you could use the conical as the heat sink to raise temp in the winter. At $13 a pop it would be cheaper than using a refrigerator to store a large conical, at least in the short run. With the price of electricity rising it would be interesting to see when the fridge would pay for itself...

 

[Catt22]

If you had a stainless conical you were fermenting with that you could maybe glue a couple to the side and run it through a controller. That could maybe keep temps down. You could even flip a couple around so you could use the conical as the heat sink to raise temp in the winter. At $13 a pop it would be cheaper than using a refrigerator to store a large conical, at least in the short run. With the price of electricity rising it would be interesting to see when the fridge would pay for itself...

"Thermoelectric cooling is generally only used in environments where the solid state nature (no moving parts, maintenance-free) outweighs pure efficiency."

 

[ClaudiusB]

I know there are some pretty technical people on here who could think of other creative ways to use these in a brewing aspect, and the prices seem reasonable.

I'd really like to hear from anybody that has used these before,

I have not been impressed with my TEC setup.

Look at danegardner solution.
https://www.homebrewtalk.com/f51/my-incubator-stir-plate-build-218408/

Cheers,
ClaudiusB

 

[starsailor]

My BIL showed me this site UnitedNuclear.com and I found these Peltier Cooling Chips to be pretty intriguing. There is a smaller one for $19 too. I may pick up one of each size and see how they work for fermentation temp control mounted to the side of a fermenter. It seems like there could be a multitude of uses for them, but I'd like to pick some up to see how well they really work.

Another cool thing about them is if you apply heat to one side, they generate electricity, so even more possibilities.

They also sell erlenmeyer flasks and crazy strong magnets, some that are strong enough to break bones if not handled carefully, but the smaller ones would be great for making a stir plate.

I know there are some pretty technical people on here who could think of other creative ways to use these in a brewing aspect, and the prices seem reasonable.

I'd really like to hear from anybody that has used these before, in any aspect, and can comment on whether the cooling capacity would be sufficient for fermentation control or maybe cooling a small chamber or draft tower.

FYI, there Peltier devices are used in a number of places, like those 12V plug in coolers have one mounted in the sidewall with the cool side and fan on the inside and the hot side outside, and Mosquito Magnets that don't require separate power use one to generate electricity with excess heat from the propane flame that generates the CO2 needed to attact the mosquitos.

 

[DeBrewer]

clipped from Wiki:

"Thermoelectric junctions are generally only around 5–10% as efficient as the ideal refrigerator (Carnot cycle), compared with 40–60% achieved by conventional compression cycle systems (reverse Rankine systems using compression/expansion). Due to the relatively low efficiency, thermoelectric cooling is generally only used in environments where the solid state nature (no moving parts, maintenance-free) outweighs pure efficiency."[edit] Us

http://en.wikipedia.org/wiki/Thermoelectric_cooling

I can't fully argue the fact that it is less efficient but I have to imagine that there is a curve to both sides of that argument based off of size and application. I "think" a compressed unit on a small scale would be much less efficient. I think in a large environment there is no doubt that the compressed is more efficient but on a small object that benefits from direct contact then I would think the peltier would be leaps and bounds more efficient. I guess I keep going back to the thought of a coke can. You can stick a coke can in a cold refrigerator or freezer and it will cool rather quickly but a peltier would lend me to think that it could cool faster based on a sub zero element making direct contact with it. I guess I haven't seen any real proof other than calculations. That may be proof enough but I haven't convinced myself of that

 

[Catt22]

From the previously quoted above stuff:

"Due to the relatively low efficiency, thermoelectric cooling is generally only used in environments where the solid state nature (no moving parts, maintenance-free) outweighs pure efficiency."

IIRC, the peltiers do not get even close to sub zero temperatures. The best I have seen them do is about 40F below ambient. Small scale or large, the efficiency of a peltier junction thingy is abysmal. Stick your can of coke in a sub zero freezer, not a mere refrigerator, and do the same comparison and I think your results might be quite different. I would not consider 5 or 10 gallons of beer to be in the "small environment" category. With adequate insulation and enough of the peltier units, I'm sure you could maintain acceptable fermentation temperatures, but at the cost of considerably higher power consumption and with very limited range. Engineering calculations are "real proof", IMO.

 

[starsailor]

From the previously quoted above stuff:

"Due to the relatively low efficiency, thermoelectric cooling is generally only used in environments where the solid state nature (no moving parts, maintenance-free) outweighs pure efficiency."

IIRC, the peltiers do not get even close to sub zero temperatures. The best I have seen them do is about 40F below ambient. Small scale or large, the efficiency of a peltier junction thingy is abysmal. Stick your can of coke in a sub zero freezer, not a mere refrigerator, and do the same comparison and I think your results might be quite different. I would not consider 5 or 10 gallons of beer to be in the "small environment" category. With adequate insulation and enough of the peltier units, I'm sure you could maintain acceptable fermentation temperatures, but at the cost of considerably higher power consumption and with very limited range. Engineering calculations are "real proof", IMO.

Yeh, they're not efficient, but they are so beautifully simple. No moving or mechanical parts and no pressurized gas. Just a little piece of semiconductor, a heat sink, some thermal grease, and a power source. Kind of like a glorified refrigerator magnet.

 

[MalFet]

There are sooo many different scenarios but I have yet to see anyone prove it. I have read through some calculations on their efficiency but truthfully they make my head hurt... I want to better understand their inefficiency in application. The thought of a fermenter that is autonomous to everything and could be maintained from a battery under power failure seems sweet but if I have missed the boat on how inefficient they actually are then please show me the light.

EDIT: I really think there is no definitive answer in that there will be a curve for each system to where peltier would be more efficient in small areas and a traditional compressed system will be more efficient in larger. Considering that the peltier method is not used in large applications(to my knowledge), someone much smarter than me has already proved this...

Not that this is a direct answer to your question, but a place to start could always be to compare efficiency and power of some of the commercial rigs. Several companies released refrigerators based on peltier junctions three or four years back. They tended not to do well because people didn't understand their limitations. They ended up with huge numbers of returns from people who would buy them to keep soda cold in 95F garages and ended up disappointed by warm Pepsi. They manage a 40 degree delta pretty darn well, but don't really go past that.

I use one of the Haier 2.7cf NuCool fridges for a fermentation chamber. There are upsides. The lack of a compressor hump means that the smallest thing out there that will hold a carboy. No compressor means it is extremely quiet. But, my understanding is that it uses about twice the electricity that a dorm fridge would in similar application.

It also takes longer to crash cool than a normal fridge does. Your coke can speculation doesn't bear out in the real world, unfortunately. You'd think the other factors you mention would have a big impact, but at the end of the day it's just thermodynamics. The peltier displaces heat less quickly and less efficiently than a compressor does. Nothing else seems to matter.

None of that is to discourage you from using a Peltier. There are other positives that might outweigh efficiency losses, and those losses aren't so extreme as to make them useless (as people sometimes imply).

 

[DeBrewer]

From the previously quoted above stuff:

"Due to the relatively low efficiency, thermoelectric cooling is generally only used in environments where the solid state nature (no moving parts, maintenance-free) outweighs pure efficiency."

IIRC, the peltiers do not get even close to sub zero temperatures. The best I have seen them do is about 40F below ambient. Small scale or large, the efficiency of a peltier junction thingy is abysmal. Stick your can of coke in a sub zero freezer, not a mere refrigerator, and do the same comparison and I think your results might be quite different. I would not consider 5 or 10 gallons of beer to be in the "small environment" category. With adequate insulation and enough of the peltier units, I'm sure you could maintain acceptable fermentation temperatures, but at the cost of considerably higher power consumption and with very limited range. Engineering calculations are "real proof", IMO.

From what I have read/watched a peltier's potential temperature is determined by it's delta T and not a specific temp. In essence if a peltier is rated at a delta T of 60, it is capable of a temp 60 degrees C different than the opposing side. So under proper cooling of the hot side(heat sink and fan), the cold side can get down rather cold even below zero. It is common practice in overclocking CPU's. Here are some examples...



and



I know I am making a stand in the face of fact but when I look at it form the standpoint of making an ice cube it doesn't seem inefficient. Take a teaspoon full of water and put it in your freezer and see how long it takes to freeze and then compare it to the time it takes for it to freeze on the peltier in the video. That thing froze in just a few seconds. Your freezer is pre chilled and still wont freeze it in that amount of time...

I know we are talking extremes here but I have to imagine that in certain applications the peltier could at least be an equal. I'm not sure a peltier setup on a larger scale could rival a sound glycol setup, but if it was somewhat comparable, the simplicity would tilt the scales perhaps. I hope to get my elements in soon so I can play.. :rockin:

I'm not trying to be difficult, I just have to think that there is an application somewhere that we can use these nerdy little awesome pieces of technology!

 

[passedpawn]

I've done a bunch of work with them, super large ones and little wafer-sized ones. You have to throw a bunch of power at them to get them to work, then you have to cool the hot side like there's no tomorrow. I'm not a big fan of them for most purposes. They seem like a good idea, but believe me they require some effort to move the heat.

I have a large 400W one I integrated into a medical device I'm developing ... it did freeze and break the copper pipes once when I forgot to add ethylene glycol into the water.


I think they have much better use as an thermoelectric energy source, harvesting energy from temp differentials. But that's another topic.

 

[DeBrewer]

I've done a bunch of work with them, super large ones and little wafer-sized ones. You have to throw a bunch of power at them to get them to work, then you have to cool the hot side like there's no tomorrow. I'm not a big fan of them for most purposes. They seem like a good idea, but believe me they require some effort to move the heat.

I have a large 400W one I integrated into a medical device I'm developing ... it did freeze and break the copper pipes once when I forgot to add ethylene glycol into the water.


I think they have much better use as an thermoelectric energy source, harvesting energy from temp differentials. But that's another topic.

By "medical device" you mean sweet fermentation chamber that yields the nectar of the gods? Don't get me wrong I am not wanting everyone to think that they are the best solution for everything, I merely would like to better understand it in our applications.