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Utah Teens Invent Better Air Conditioner
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."
Frigidaire got to them. Don't mess with the cooling conglomerates...
"Waste not one watt!" - CZ
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When all you have is a hammer, everybody looks like a Messiah.
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.
Putting moderation advice in your
Ahh, I "read the fucking article" and now I understand. The main article makes you think a couple of chips save the day, and makes A/C's last longer. They do, in a way, but the article on ./ here should have quoted the real article, instead of trying to paraphrase.
"Today, the young inventors say, U.S. drivers use about 7.9 billion gallons of fuel each year to run their air-conditioners, which draw power from the engine. By adopting their contraption - which taps into the electrical system, using fans to blow hot air through five Peltier chips and then releasing cold air - they say the country stands to save 3.9 billion gallons of fuel annually, or about $10 billion based on current gas prices."
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!
bash: rtfm: command not found
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?
The truth shall set you free!
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?
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Yeah, this article sounds like "really, really bad misunderstanding of science".
The reason why the Peltier effect isn't used everywhere a heat pump is needed - and it's a really neat effect, mind you, as it has no moving parts, little to get corroded, is small and lightweight, etc - is that it's inefficient. We're talking god-awful inefficient until recently (~5%), and even now we're trying to stretch it to ~20% in the lab (no easy task).
As another poster mentioned, conventional refrigeration systems are quite efficient - at least, by themselves. Now, for a home refrigerator, it doesn't work out so nicely, because your power is being generated at 50% efficiency, transformed multiple times at a loss, suffers transmission losses on the way to your house, etc (that's why propane and even solar refrigeration systems are more efficient). But for a system like in a car, where the motor is directly running the compressor, it's going to be very efficient.
The Peltier chips - inefficient on their own - suffer from the inverse problem that the refrigerator suffers from! They need DC electrical power, but what the car engine produces is mechanical power! The car's alternator produces AC at a loss, which is rectified to DC, which then goes to the lossy Peltier chips. Assuming "ebay chips" are, say, 5% efficiency, we're looking at an overall system efficiency of 1-2%. Yeah, great way to save gas.
Point of interest. Offering to shoot us might not work so well as an incentive as you might imagine.
Domestic fridges are the most reliable applicances in the home because they are built as a completely sealed unit.