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Technology Science

Utah Teens Invent Better Air Conditioner 755

Posted by samzenpus
from the stay-frosty dept.
Carl Youngblood writes "Two recent Utah high school graduates won the first-ever Ricoh Sustainable Development Award for inventing a better car air conditioner based on the Peltier effect. The peltier chips used in the device are more energy-efficient, last between 20 and 30 years, are solid-state, and don't harm the environment with ozone-depleting freon like today's car air conditioners."
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Utah Teens Invent Better Air Conditioner

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  • /.ed (Score:3, Funny)

    by GoogolPlexPlex (412555) on Wednesday July 20, 2005 @10:48PM (#13120679)
    I wish they had built a better server.
    • by aapold (753705) on Wednesday July 20, 2005 @10:50PM (#13120694) Homepage Journal
      Frigidaire got to them. Don't mess with the cooling conglomerates...
    • Free peltier [freepeltier.org] with rebate.
      *informative, stupid*
  • by ToadMan8 (521480)
    Cars sold in the states haven't used Freon since the late 90's. That's why A/C sucks in cars now.
    • by name_already_taken (540581) on Wednesday July 20, 2005 @11:02PM (#13120788)
      Freon is trademark used for a variety of nonflammable gaseous or liquid fluorinated hydrocarbons which are no longer used as motor vehicle refrigerants.

      The current refrigerant, hfc134a contains no chlorine (the ozone damaging part of R12) and has an ozone depletion potential of zero.

      The idea of using Peltier devices is interesting, because there'd be no mechanical parts to wear out, or refrigerants to leak out, so the system should be much more reliable, but I thought Peltiers would require a huge amount of current to do as much cooling as a car A/C system delivers.

      • by alienw (585907) <alienw,slashdot&gmail,com> on Wednesday July 20, 2005 @11:50PM (#13121064)
        I thought Peltiers would require a huge amount of current to do as much cooling as a car A/C system delivers.

        The car's electrical system is not suited to supplying significant amounts of power. A typical alternator tops out at about a kilowatt of power (80A or so). Due to the low voltage, ridiculously large currents are necessary.

        Of course, a peltier is much less efficient than a compressor system. A compressor typically has a coefficient of performance (COP) of around 3, meaning that it removes 3 units of heat for every unit of supplied work. For peltiers, this value is around 0.4, which is a huge difference. Thus, the peltier would consume about 7x more energy to supply the same cooling capacity. This is the main reason cars don't use peltier A/Cs.
        • Yeah, I think people are missing simple facts here.

          Pelters aren't very efficient.

          Furthermore, if they were a good means of cooling things, we would use them for everything, but they don't thus why some kids build it, and corporations don't. If would be massively cheaper for them to use and have nothing but benefits. But they suck for the job, thats why they don't use them.

          But people seam to be missing that part of this thing. I'm guessing all the articles are gone cause someone pointed out how bad a st
    • All cars with A/C still use freon. They don't use R-12!! (which is the stuff that supposidely depletes the ozone, and has been illegal since about model year 1995, NOT the late '90s)

      Freon != R-12
    • by pongo000 (97357) on Wednesday July 20, 2005 @11:04PM (#13120802)
      This should actually have been modded as "misinformed" (don't we wish...)

      R134a A/C systems have evolved over the years. Granted, the early systems left a lot to be desired, but the output of the recent systems rival that of old R12 systems. R134a systems are very pressure-dependent, far more than R12, and must be precisely charged for maximum effectiveness.

      It's hot here in Texas, at or above 100F in the summer, and both of my Chevy trucks (an '02 and an '03) blow frigid air.
  • freon? (Score:2, Informative)

    by schematix (533634) *
    The peltier chips used in the device are more energy-efficient, last between 20 and 30 years, are solid-state, and don't harm the environment with ozone-depleting freon like today's car air conditioners."

    Ahem. "Today's" cars use R134a refrigerant, not ozone-depleting freon. This has been the standard for a little less than ten years now.

    • Re:freon? (Score:5, Insightful)

      by Technician (215283) on Wednesday July 20, 2005 @11:37PM (#13120994)
      In the new Prius, the AC is no longer belt driven. This eliminates the shaft seal, a common wear and slow leak source. The new AC is electric using a sealed compressor much like a home AC unit.

      The peltier chips used in the device are more energy-efficient, last between 20 and 30 years,

      I have a solid state ice chest. I don't believe the expected life rating when applied to a solution where condensation is present. It does not apply when they are used in high humidity. Corrosion from condensation kills these in a very short time. The module in my fridge died long ago from condensation caused corrosion. I would not want these in any application that runs below the dew point. Since my AC in my car is designed to run below the dew point to defog windows, there is no way I want a cooling solution that dies when it gets wet. Speaking of more energy-effecient; More effecient than what? Older modules, compressor driven? I have not seen any peltier chips ready to replace the compressor driven freezers and window AC compressors. They simply don't remove enough heat.

      An advantage a working fluid AC has over a solid state solution is the hot side can be far removed from the cold side. The radiator for most car AC units is in front of the engine in cool air. A solid state AC would have the hot side behind the engine next to the passanger compartment. Just where were they planning on putting their waste heat? A typical car AC unit is over 20,000 BTU's. How many BTU is their system?
  • sweet! (Score:2, Funny)

    by sams2100 (237327)
    I can now overclock while I drive!
  • Now I can overclock my car's OBD-II computer.
  • Google Cache (Score:5, Informative)

    by j00bar (895519) <slashdot.flowtheory@net> on Wednesday July 20, 2005 @10:50PM (#13120698) Homepage
    If you're having trouble seeing the article, try this: Google Cache [64.233.167.104]
  • by DarkHelmet433 (467596) * on Wednesday July 20, 2005 @10:53PM (#13120728)
    Freon (R-12) hasn't been used in new cars for something like a decade now. R-12 is an ozone depleter. It hasn't been manufactured in the US since the mid 90's or so

    Newer car air conditioners use refrigerant R-134a. This is *not* an ozone destroyer, but it is still a greenhouse gas.

    Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

    It's all bad. :-(
    • by Muerte23 (178626) on Wednesday July 20, 2005 @10:58PM (#13120766) Journal
      Peltier coolers use electricity, which is generated by the horribly inefficient internal combustion engine which produces greenhouse gasses and other toxins by the boatload.

      Not to nitpick, but the compression cycle of regular car AC is also powered by the motor...

      Plus, if your alternator can handle it, the peltier is probably much lighter, and certainly much smaller, further improving your engine efficiency.

      m
      this is not a sig
      • by dbIII (701233) on Thursday July 21, 2005 @12:44AM (#13121338)
        Not to nitpick, but the compression cycle of regular car AC is also powered by the motor
        Yes, but it is far more energy efficient than a thermocouple driven in reverse. There's good reasons why this sort of thing wasn't done fifty years ago in this situation, but was done fifty years ago where space was tight and energy efficiency was not the issue. We have known about the physics involved and the materials used here for decades - peltier cooling has just come to prominance lately because it's a way to cut down on the number of moving parts and is getting into home computers.

        These kids won against others because they did something others with knowlege knew was no big deal, and those that judged only looked at it superficially and thought it was a big deal.

        It reminds me of a famous artist that developed an apparent way of dramaticly inproving fuel efficiency in internal combustion engines. By putting a spacer under the carby he optimised the motor to run while idling, dramaticly reducing the amount of fuel it used on a test bed - because the motor had been optimised to run at a specific load. He completely missed the point (that you want the motor to do something) and the press didn't realise either. The judges in this competition have also missed the point and gone for drama over utility.

    • by ErichTheWebGuy (745925) on Wednesday July 20, 2005 @11:19PM (#13120886) Homepage
      OK, allow me to put some things into perspective. In addition to being a MCSE, A+, etc. certified geek, I also hold EPA certification to handle refrigerants and to service and install refrigeration systems in commercial, residential, and automotive applications.

      The parent poster is absolutely correct, R134a is a greenhouse gas. However, that statement should be qualified: it is only a greenhouse gas when it is released into the atmosphere. Modern technicians use recovery equipment to remove refrigerants from cooling systems (everything from your freezer to your central A/C). The refrigerant is either recycled, or disposed of properly.

      As long as we are all conscious about our environment (and we all should be, lest anyone turn us in to the EPA, causing us to have to fill out the reams of paperwork!) there is no problem. Oh, and there is always that pesky thing about preserving the planet for generations to come :)

      I, for one, am quite sick of people blowing things out of proportion when there is no real problem. Having said that, kudos to the two teens for their inventive spirit. Maybe with some refining, the invention will prove more efficient and ultimately prove commercially useful!
      • by Hugonz (20064) <hugonz AT gmail DOT com> on Thursday July 21, 2005 @12:13AM (#13121166) Homepage
        In addition to being a MCSE, A+, etc. certified geek

        Syntax error.

      • As a certified firefighter and geek, I can tell you that we certainly do not "use recovery equipment to remove refrigerants from cooling systems" when we arrive at an incident. Instead we are a little busy cutting people out of cars, extinguishing car fires, extinguishing house fires and the like. There are plenty of opportunities for this stuff to leak into the environment and if we do not have to use it, so much the better. BTW, does burning it turn it into a worse chemical?
  • by kevcol (3467) on Wednesday July 20, 2005 @10:55PM (#13120744) Homepage
    ...let's go back in the Slashdot wayback machine and laugh at the last air conditioning article. [slashdot.org]
  • RSDA Press release (Score:2, Informative)

    by mabinogi (74033)
    Here's [ricoh-sustainability.com] the press release from the awards themselves, since TFA is dead.
    (PDF)
  • by GrpA (691294) on Wednesday July 20, 2005 @10:58PM (#13120765)
    Vapour phase airconditioning uses direct power from the engine, which often has an output of 100+ Kilowatts. More in a recent design.

    No one notices a few Kilowatts disappearing. Except ricers.

    Peltier devices come from the Altenator with an output capacity of around 1Kw or less, And most of that is used by Lights, Engine management etc... And for charging the battery

    There's not a lot of electricity spare to run a Peltier based cooling device.

    I've built something similar myself for a car once, but it only provides piped air - and didn't have to cool the whole cabin.

    A 12 amp peltier device consumes a LOT of power... About 150 watts Not all cars can spare that much. And it doesn't cool much either.

    I'm sorry I can't get the article up though. I really wanted to read it :(

    Good on them though for experimenting :)

    GrpA.
    • "Vapour phase airconditioning uses direct power from the engine, which often has an output of 100+ Kilowatts. More in a recent design."

      Not necessarily. The Toyota Prius, for example, uses an electric (144V AC) A/C compressor. Of course, it's the exception, not the rule. The Prius has a high-voltage battery system and a powerful inverter.

      "A 12 amp peltier device consumes a LOT of power... About 150 watts Not all cars can spare that much. And it doesn't cool much either."

      True. 150W is a lot to ask of a typ
    • If no one notices a few kW disappearing due to A/C load other than ricers, than why do all modern cars disengage the A/C clutch when you go wide open throttle?

      If you push the pedal to the floor with the A/C on you'll get your performance, at the cost of warmer air until you are done.

    • "can't tell"? (Score:5, Interesting)

      by SuperBanana (662181) on Wednesday July 20, 2005 @11:43PM (#13121037)
      No one notices a few Kilowatts disappearing. Except ricers.

      I'm sorry, but you're completely full of shit. Every time my A/C compressor clicks on while I'm driving, I can tell; I drive a manual, and if I'm paying enough attention, I can tell especially if revs are low (ie 2k).

      Vapour phase airconditioning uses direct power from the engine, which often has an output of 100+ Kilowatts.

      You are making the assumption that the engine produces its power evenly across the band, which is outright garbage. Most engines make much more horsepower at high engine speed; better engines tend to keep making that power the closer they approach redline (at high engine speeds, resistance in exhaust and intake paths kills horsepower because volumetric efficiency drops).

      The engine will not make NEARLY as much power down at ranges people typically use; ie 2000 to 3000 RPMs. Example- the current Ford Mustang engine (no, I don't drive one- just the first chart I could find) makes 250HP at 5,000RPM+. At 2,500 RPM, it makes 100HP. The chart started at 2,500; numbers probably drop to 50HP at 2000. Suddenly, an AC compressor that uses several HP becomes a two-digit percentage of total engine output. While humans suck at absolute measurements, we can be -really- good at picking up on the finest relative differences.

      Also, maximum claimed horsepower is often under ideal circumstances; ie cool air temps, engine cold/warm not at full operating temp, lightweight oil, and at sea level. It's also always on a perfectly functioning engine; ie fresh air cleaner, ignition bits are all new, perfect compression in all cylinders, etc.

      • Re:"can't tell"? (Score:3, Informative)

        by GrpA (691294)
        >>No one notices a few Kilowatts disappearing. >>Except ricers. >I'm sorry, but you're completely full of shit. >Every time my A/C compressor clicks on while >I'm driving, I can tell; I drive a manual, and >if I'm paying enough attention, I can tell >especially if revs are low (ie 2k). That's because you're a ricer - I can tell from your response ;) (Tongue in cheek) Heh. Don't take that seriously. I'm not trying to start a flame war. And I apologise if you took exception to m
      • troll (Score:3, Insightful)

        by shiftless (410350)
        I'm sorry, but you're completely full of shit. Every time my A/C compressor clicks on while I'm driving, I can tell; I drive a manual, and if I'm paying enough attention, I can tell especially if revs are low (ie 2k).

        Of course you can tell when it clicks on. However, in 99% of the cars out there, the A/C does not effect driveability a noticeable amount.

        This was the grandparent's point. So the air conditioner takes up, say, 5% of your engine power while you're cruising at a low RPMs. Big deal. Maybe the c
      • Re:"can't tell"? (Score:3, Interesting)

        by Lumpy (12016)
        dude, your headlights use more power than the air conditioner in a modern car.

        Turn off your headlights and your foglights (driving with them on makes people look like a dorks anyways) and you will have more than enough power restored for the AC.

        My econobox that get's 42mpg went up to an average of 43mpg when I disabled the Daytime Running lights that was simply a diode that was turning on the headlamps when the car was running.

        granted i drive highway speeds 909% of the time, but ther are many more power
        • Re:"can't tell"? (Score:3, Insightful)

          by gillbates (106458)
          dude, your headlights use more power than the air conditioner in a modern car.

          Um, dude, you're wrong. Ford claims that the air conditioning compressor alone will use 25 HP on a hot day.

          Your headlights, OTOH might use 10 or 20 amps. At 13.5 volts, thats 270 watts max. Or about 1/3 of one horsepower.

  • by WindBourne (631190) on Wednesday July 20, 2005 @11:01PM (#13120782) Journal
    • The students' research estimates their system would cut millions of pounds of hydrocarbons and nitrous oxides, and billions of pounds of carbon monoxide found in vehicle emissions. It also would increase gas mileage by four miles per gallon and hike horsepower by as much as 4 percent -- saving American drivers billions of dollars in annual gasoline costs.

      Since when do they hand out awards for bad research at best or out-and-out lying. A peltier effect heat pump has a COP of around .3 and a typical R134a
  • by ErikZ (55491) on Wednesday July 20, 2005 @11:02PM (#13120787)

    Wasn't there supposed to be a new 48v electrical system standard for all cars by now?

    It would allow people to hook up better electronics to their vehicle, plus it would make the car more energy efficient. The example I heard was that instead of a belt driven AC unit, it would be electical.

    The article I had read at the time stated that the standard would be implemented in 2005. Does anyone know about this?
    • It would allow people to hook up better electronics to their vehicle, plus it would make the car more energy efficient. The example I heard was that instead of a belt driven AC unit, it would be electical.

      The article I had read at the time stated that the standard would be implemented in 2005. Does anyone know about this?


      The only car I know of with an electric sealed compressor instead of a belt driven compressor is the 2005 Prius. It runs off the 400 volt hybrid battery, not the low voltage side of thi
    • It's Actually 42v (Score:3, Informative)

      by mrdrivel (742076)
      The new standard calls for 42v not 48. [iee.org]

      It looks like there is the Toyota Crown Royal which uses 42v and a "new SUV from GM" that will use 42v as well. Source. [66.102.7.104]
  • by dpdawson (624716) on Wednesday July 20, 2005 @11:03PM (#13120794) Homepage
    More efficient?
    Last longer?
    Better for the environment?

    It'll never catch on.

  • hey! (Score:4, Interesting)

    by austad (22163) on Wednesday July 20, 2005 @11:07PM (#13120816) Homepage
    I built one of these back in 1999 with some peltiers I ordered direct from a manufacturer, some old heatsinks, case fans, and bent tin sheets.

    It fit in the window, just like a regular ac unit, but it didn't stick out at all. Basically, it was just two layers of heatsinks with the peltiers sandwiched in between. The hot side faced out the window and fans forced air on them to cool them, and the cool side faced inwards, with fans along the lower edge, a sheet of tin across the middle to make the air flow more over the fins, and an opening on top where it blew into the room.

    It worked well for a small room. I suppose if I had the money at the time, I could have purchased some massively power hungry units and been able to get some crazy cooling power out of it. I probably still have it in a box somewhere.
  • by YesIAmAScript (886271) on Wednesday July 20, 2005 @11:23PM (#13120912)
    Peltiers do not work very well and are not as efficient as a phase-change (freon-type) system. You can prove this to yourself by buying a Peltier-based portable cooler at Target (they've been available for 20 years, search for "coolerator") and a $99 phase-change based cube fridge. The Peltier can barely get a six-pack to 35 (F), the cube fridge can make ice in a 1+ cubic-foot space.

    This is just total bunk. The only way it saves energy is by not cooling as much.

    Honestly, I think that the only threat to phase-change systems in small systems is sonic cooling. It could be more efficient, require less maintenance and have less environmental impact than a phrase-change system.

    Evaporative systems are nice too, especially for large installations, but don't work for getting much below ambient.
  • by TRRosen (720617) on Wednesday July 20, 2005 @11:28PM (#13120939)
    1. works with electric cars

    2. unit can be in passenger area and not in engine compartment

    3. you could have several small units instead of one big one

    4. flip the peltiers and you have a heater

    5. no pulley being spun even when not in use

    6. should be much lighter (although alternator would get bigger)

  • by DasBub (139460) <dasbub@[ ]bub.com ['das' in gap]> on Wednesday July 20, 2005 @11:55PM (#13121083) Homepage
    Let's set the record straight, here.

    The noun "Freon" has a double meaning. Strictly speaking, it is the trademark name of refrigerant R-12, a single product of a specific formulation.

    Due to its popularity it has become a sort of catch-all term used to describe an entire family of products. Much the same way that all couches can be called Chesterfields or all tissues can be called Kleenex, Freon can be used to describe a family of refrigerants.

    As well all know, the actual Freon refrigerant, R-12, has been banned for a decade now. In this way, it is proper to say that no air conditioning unit in the US, Canada, etc., made since 1995 uses Freon.

    The currently widespread refrigerant is R-134a, trademark name "Suva". It's chemically different from "Freon", but can be described as being part of the Freon family. This can make casual discussions a bit muddled as everyone argues whether or not Suva is Freon... Well, maybe I'm the only one having that type of casual discussion...

    So, to make a short story long:

    Freon is a Freon, Suva is a Freon, but Suva is not Freon. Got it?
  • by gerardrj (207690) on Wednesday July 20, 2005 @11:59PM (#13121101) Journal
    If you've had your hands on a peltier, you've probably sandwiched the thing between two heat sinks and two fans. One side is a heater, the other is a cooler. This is the exact method of operation of those in-car cooler/heater boxes you plug in to the cigarette lighter. These kids are simply scaling the idea up; instead of cooling a box in the car they're cooling the car.
    There is nothing novel or innovative about this.
  • by Ancient_Hacker (751168) on Thursday July 21, 2005 @06:50AM (#13122766)
    Let's count the things tha are completely and verifiably wrong in the article:
    • Peltiers are efficient-- NOT! They have an EER of way less than 1.0. A window air conditioner is above 10. End of discussion.
    • There's no way to make them more efficient-- think-- they have their cold side right next to their hot side-- there's a lot of thermal conductivity there, effectively undoing a big percentage of the cooling.
    • It's NOT more efficient to draw electrical power than to draw engine power. Somehow the kids think the alternator turns for free. Nope, it draws engine power just like the old AC, and as all defvices are less than 100% efficient, it has to be LESS efficient to use the power downstream from the alternator. { Minor caveat-- the alternator has the advantage of being able to put out more constant power-- direct drive from the engine to the compressor results in less AC (but not necessarily lower efficiency AC) available at slow engine speeds.)
    • A typical auto AC puts out 30,000 to 50,000 BTUS/hr of cooling. A 1x1 inch peltier chip does about 150 BTU/hr at a cost of $9.95 on the surplus market. To duplicate a regular car AC would require 200 to 350 chips, $2000 to $3500. Plus a bunch more alternators, they'd need 1400 amps, about 20 alternators. Hard to fit them all under the hood.
    • Peltiers do not last forever. They're prone to breakage due to cyclic stresses and degradation from humidity.
    A REALLY bad aricle. The laws of thermodynamics rule.
  • Clueless kids (Score:4, Interesting)

    by wowbagger (69688) on Thursday July 21, 2005 @07:18AM (#13122901) Homepage Journal
    These kids ignore the facts that:
    1. Peltiers are MUCH less efficient at moving heat than mechanical phase change coolers.
    2. The electrical energy to drive the Peltiers will come from somewhere, namely the alternator.
    3. The increased load on the alternator will in turn cause the alternator to place an increased load on the engine, reducing gas milage.


    These kids didn't really test their system - as in, make measurements of fuel economy with the old system and with the new system in real conditions and see what the difference was. They just assumed that "If we get rid of the load from the compressor, we will save 10 HP that will save X amount of fuel" (ignoring the load from the alternator).

    Now, if they had wanted to REALLY do something that would cool the vehicle without costing more gas, they would have mated an adsorption cooler [lpappliances.com] to the exhaust manifold, and recovered the energy to run the cooling system from the waste heat discarded to the atmosphere.
  • A few points (Score:3, Informative)

    by Muad'Dave (255648) on Thursday July 21, 2005 @07:25AM (#13122953) Homepage

    • As has been mentioned, this isn't exactly a new invention or particularly innovative. As we've all seen from the patent office's behavior, something can be seen as innovative and blindingly obvious at the same time.
    • Many posters have commented on the amount of power needed to run Peltier's - remember that in the not-too-distant future cars will have 48-52V electrical systems with alternators capable of much higher power output. Car's electrical systems are already taxed given the recent proliferation of nav systems, DVD players, laptop power outlets, etc., so the move to more powerful electrical systems is underway.

      Here are a few of the things that become possible with that kind of available power:

      1. Engines with electrically-actuated valve trains - no more camshaft, timing belt, rocker arms, pushrods, etc.
      2. Electrically powered power steering (as is done on my Mini Cooper S), eliminating that belt.
      3. Electrically powered A/C system
      4. The alternator either integrated in the block, or bolted directly to the crank. Imagine that - an engine with no belts!

    • Wouldn't it be interesting to develop a cooling element that combined the Peltier effect and the Piezoelectric effect? Anchor one end and let the other flap, apply pulsed DC to it and you get cooling and a fan!

We don't know who it was that discovered water, but we're pretty sure that it wasn't a fish. -- Marshall McLuhan

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