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PeltierBeer
Helstein writes "Finishing a beer in the sun before it gets warm is usually not a problem, but what about those really hot days? Having some hardware lying around there is only one solution to keep the beer cool, that's to make a PeltierBeer."
See also the jet-powered beer cooler.
Why do I remember that? <sigh>
Note, IE. Ireland. The real stuff.
The URL is a complex one and behind an age check, so you may need to go there yourself. Products, Guinness Draft and in Cans.
Warm Guinness? Ick! It's supposed to be ice cold, and that's the way I love it. Okay, maybe you're German... I know a two exchange students that like warm beer -- to the point they'll use a small immersion heater. But warm Guinness? Surely you must be daft!
Granted, Per Øyvind Arnesen is using Guinness Draught in a can, and my supply is current the "rocket widget" bottled version... but as I recall the advice on the side is the same:
- "To really enjoy Guinness Draught, chill for at least 2 hours."
There you have it, straight from the side of the bottle."...America's great minds of today, teaching America's great minds of tomorrow. Poor bastards." -- A Beautiful Min
Well, amperage determines the heat that will be generated with power flowing through the wire, thus bigger wires for higher amperage, but high voltage has this nasty tendency to penetrate weak insulation...the higher the voltage the greater it can penetrate through insulation...ever seen those van degraf generators that make your hair stand on end =) or those cool orb thingies like in that movie the Wizard or something.....ahhh, i digress
We've secretely replaced the Enterprise's dilithium crystals with Folgers crystals. Lets see if they notice.
Ever heard about PoE (Power over Ethernet)? While not really a standard yet (afaik) it seems to work.
Of course it runs NetBSD. BTC: 1NT7QvbetmANwaMzhpVL6
The sort that you get in a pub, not the sort that you get in a can or bottle. Most pubs in Ireland serve Guinness either at room temperature or slightly chilled (around 12 C / 53 F).
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
...there's a reason he doesn't post any real data regarding how much colder it kept the beer than without the cooler.
I quote from the last page of his site, which was not at all difficult to miss if you rtfa - " The temperature in the glass was roughly 22C before I poured in the beer. The beer is from the fridge and has a temperature of 8C." and then "The temperature stabilized around 7C."
These comments on the temperatures being interspersed with pictures of the thermostat showing it in action.
Granted, he doesn't talk about the performance before hand, but since the first picture shows a baseline of 19 C outside and the temperature stabilzied colder than fridge temperature, I'm assuming it was quite effective.
"This is Zombo Com, and welcome to you who have come to Zombo Com" - www.zombo.com
It's the peltier element that's the key here. Using electricity you can make one side of it turn really cold (I think into negative degrees C) while the other side gets hot (very simplified). In the article: "I discovered that the thermometer could not display temperature under 0C". The resulting heat on the hot side gets blown off by the fan. The cold side is attached to the beer mug. I think the surrounding temperature doesn't matter that much here.
Of course it runs NetBSD. BTC: 1NT7QvbetmANwaMzhpVL6
The room-temperature thing is a just a piss-take on the pedantic Yanks.
Just think, you've been doing it wrong all this time.
--kotj.mf, who has been in an actual Irish pub.
hang brain.
Yeah I made the exact same mistake. What you and I missed is this. Hence the name "PeltierBeer Cooler." I'm trying to not be too condescending since I posted a message earlier making the exact same mistake. Physics behind these things are actually pretty cool and you can use them in reverse by making one side hotter than the other and it will produce electricity.
Hi, MacDork. Yes, your understanding of thermodynamics is probably ok. It's your ability to read the article and grok it that's coming up short.
He used a Peltier junction. Look it up. It's an active, solid-state, heat transfer device. It can move heat against the thermal gradient, when supplied with power.
IOW, run current through a Peltier and one side gets colder than ambient, and the other side gets warmer. Reverse the current, reverse the effect. Add a fan to the hot side to get rid of the heat, because they are limited to a max temp differential between the sides.
Ce n'est pas un vrai mouvement de robot!
Come on mods what part of peltier did you not understand in the slashdot summary?
A peltier device can make a difference of +/- 20 degrees difference from the ambient temperature.
I experimented with a similar idea, using a peltier cooler and heatsink removed from a dead Macintosh workgroup server. The thing already looks like a coaster (The heatsink is rounded), though I was mainly using it to keep coffee hot, though with a reversible switch it was up to the user.
Couple of suggestions for the guy:
1. Don't run the fan when on batteries, at the Ampage you are getting from the batteries, the peltier isn't going to self destruct, you might as well stretch the battery life. (I've used a low amp peltier without a fan for this purpose without problems)
2. Use an aluminium cup. What was the point of using an insulating drink cup, then placing on a cooling element? I've used an aluminium mug, and achieved relatively good cooling and/or heating.
Obviously it's not going to keep it hot/cool forever, but it slows its return to room temperature. (Then again I was using a low power peltier)
Ales in the british tradition are typically served at "cellar" temps -- around 55F-60F. Continental lagers are best a little colder but generally not below 45F. A few belgian styles do better even colder, but never ice cold (38-45F).
If served ice cold, beer tends to lose most of it's flavor and seems thinner. The same is also true to a lesser extent with increasing carbonation. In the case of an american pilsener like bud, you're not missing much if the beer is ice cold. In the case of a fine czech pilsener like Budvar, you'd be missing a lot.
Roving Web-Teleoperated Robot
Of course it would matter. Voltage is proportional to Current i.e. V=IR, I=V/R. R is pretty much constant, and the Cat5 cable is most likely made of copper. If you run 10,000V through Cat5, it'll probably overheat and breaks, unless the cable is very, very long. You won't get blue smoke, though, because that usually comes from the silicon used in electronic components that overheats.
Yeah, right.
Ok, let me get this straight, he's running 12v down a regular ol', totally otherwise normal, completely unmarked, grey piece of unassuming CAT5 cable...
How long until something releases its magic blue smoke?
Probably not until he gets a short as the peltier probably doesn't draw much current at all, but a short in the cable would take advantage of all those rich chunky amps the computer PS can generate. Ever notice that shorting the +12 or +5 lines on a PS usually doesn't shut it down?
I've seen 12vdc, 24vdc and 110vac run over Cat5 and they do fine, longest run was of the 24Vdc - ran about 200-300 feet with no problems. I've also seen 110Vac run over a scsi-1 cable with no problems. It's current more than voltage.
Good judgment comes from experience, and a lot of that comes from bad judgment.
Beer looses all its taste when it gets too cold, which should tell you a lot about the stuff they sell in the states as beer.
Some friends of mine used to have a beer tasting contest. Everyone brought their favorite brew, everyone tasted each and then were blindfolded and had to try and identify brands. One year, two guys managed to identify all 50+ brands. To break the tie, we went and got every bad light American beer we could find. We put them in a freezer to absolutely kill any taste. Result? The two winners were able to identify all of the light beers. Maybe it was a statistical fluke, but these guys seemed to think that even near frozen light beers have distinct identifiable tastes.
FreeSpeech.org
In america you need to know your Guiness. *Most* stores sell the shit made in Canada, and yes, that is not Guiness. The stuff in the bottles is closer, but still a little funky. But some markets sell the real import from St. James Gate, and there you have a real Guiness -- and yes, I've had it on tap, its the same.
I think he is not concerned with actually running the 12vdc down the CAT5e cable, the wire thickness should probably handle anything up to 110v fine; he is more concerned with someone possibly plugging the live CAT5 cable into an unsuspecting NIC. I don't think most ethernet cards are equipped to handle 12VDC down the sense lines with probably 3-4amps. And that's when you'll see the magic smoke escape.
Actually peltier devices are very power-hungry, they need a LOT of current (3-4 amps) to work at high temperature differentials, which is desirable in this case. But I agree that the Cat-5 should stand up to that kind of power, especially if he just shorted 1-4 and 5-8 and used them that way.
- "Nobody came out that night, not one was ever seen. But Old Man Stauf is waiting there, crazy sick and mean!"
The heat transfer coefficient for glass isn't as high as metal. Sure it's proper to drink guiness from glass, but if you want to increase the efficiency, use a metal drinking vessel. Also, use something that is flat bottommed to increase contact area. Better yet, use thermal adhesive to permanently stick a metal drinking vessel to the copper plate... that stuff will lower contact resistance quite a bit.
The Afrotech Ghetto Hardware Fun site has early, failed experiments in peltier beverage cooling, with dangerous results! He almost had it right in his second experiment though...
1 calorie = amount of heat required to make 1kg of water 1 degree hotter. 1 BTU = amount of heat required to make 0.454kg of water 5/9 degree hotter.
..... um, sod it, keep the figures round, assume 0.5kg of beer. So the total heat capacity will be 2100J K-1 - i.e. it will take about 2000 watt-seconds of energy to make your beer a single degree hotter - or, to make your beer colder, you will have to extract that much energy from it.
Heat capacity of water = 4170 J kg-1 K-1.
Beer is 90-odd % water. Assume HC of beer is 4200 J kg-1 K-1. Now of course we need to get the mass of our beer; the cans are only labelled by volume. A full pint is 568ml, a standard beer can is normally 440ml. Now we need a figure for the density
For 0.5 K min-1 cooling (which is what cheap environmental chambers are spec'ed at) that means drawing out 2000J in 120", which is 17W. If the cooler needs 1W in to get 1W through (2W out), then it will be running 34W, or about 3A at 12V. And this is only half a degree a minute!
Je fume. Tu fumes. Nous fûmes!