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Car Powered by Compressed Air
gripperzipper writes "CNN reports that a Korean company created a small car powered by compressed air. ENERGINE created its PHEV, or Pneumatic-Hybrid Electric Vehicle, which uses a two-stroke compressed air engine for start, acceleration, and uphill climbs. The car switches to an electric motor when its speed reaches 20-25 km/h (32-40 mi/h). Although major auto manufacturers have invested heavily in gasoline hybrids, it will be interesting to see if a market will open for this type of vehicle." Update: 04/04 17:18 GMT by T : Reader Tapsu spotted the incongruity here, writing "Interesting post, but the speed conversion has gone wrong way: "20-25 km/h
(32-40 mi/h)". ... Thus the correct speed range in miles would be
something like 12-15 mi/h."
I hope it has an external refil port for the compressed air tank. This will be a great way to take advantage of stations that offer "Free Air" (and also, unfortunately, prompt a decrease in the number of stations offering "free air"...)
But does it take more electricity to compress the air into the tank than it does to just run the car on electric power? Sounds like just another degree of separation from energy we'll be getting from oil, anyway.
It would be cool if it didn't suck.
Havn't they had something like this comercialy avalible in France for a while IIRC? Its has a ridiculously strong carbon fiber airtank that's presurised at home by a compressor using off the grid electricity. Its basically a small comuter car, but it has decent range and speed.
"Sic Semper Tyrannosaurus Rex."
This website provides the perfect fuel for this car.
But I'm probably just repeating the first several dozen comments...
I hear they're almost as volatile as tanks filled with explosive refined hydrocarbons!
The car swtiches to electric when it reaches 25 km/hr according to the Energine website which is actually more like 15 miles per hour.
From the manual:
"Should you find yourself approaching the state of being in an accident, please yourself to duck so as to avoid looking at your previously attached body before the shrapnel took off your head." (Safety tips, Appendix A, P.232)
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
Here is another take on the same story, but with a little bit more science. The bottom line is there's no such thing as free energy... or lunch. You don't get owt for nowt. CNN needs to learn science
First off, like someone said, that the energy it takes to compress the air can be inefficient and still polute the air if the energy to compress came from fossil fuels/coal. Secondly, while it is an "Engineering Marvel" to drive up a hill using compressed air, it's very dangerous. For any of you who have ever worked on high pressure AC systems, any pressure higher than 500psi or so can be deadly if anything at all goes wrong. It's not like a battery, where a little acid can spill if it's broken. Nor is it like gasoline, cars are built to prevent explosions, and the worst case scenario is lots of fire. If you puncture a high pressure tank or lines, you have a disaster on your hands; theres no avoiding it. Besides, the entire problem with a gas induction engine is that they are horribly inefficient anyways unless they are running at their optimal RPM.
Now we know why this car keeps crashing into Mars.
The high pressure tank in that vehicle is charged to 300bar, or 4350psi.
That's higher than a SCUBA tank and it requires some heavy duty air compressor rigs to charge it.
I'd hate to be anywhere around that car in a crash or if it catches fire...
It switches to electric at 25, what happens at 80?
There are french cars that run completely on compressed air around for years.
http://www.gizmo.com.au/go/3523/
slashdot, wake the fsck up.
This compressed air engine isn't directly related to a environment-friendly fuel. The fuel of the car itself isn't compressed air - it's electricity, the battery. Electric cars, or hybrid cars, have the problem that they can't obtain high torque instantly. However, compressed air does give high torque. The idea is to store compressed air in a tank, and use it as a booster when high torque is needed. The air will be compressed later on with another compressor.
Now, combine the compressed air engine with an hybrid car. You get an hybrid car with instant high torque when needed.
They are far safer in a fire, too. If there is an overpressure in the cylinder, the gas is slowly vented, where it burns. With a petrol tank, as the fuel heats up the pressure rises until the tank bursts (because they're either plastic or thin steel).
The line should read:
The car switches to an electric motor when its speed reaches 20-25 mi/h (32-40 km/h).
If the Toshiba announcement about a better traction battery is correct. Electric motors can have practically an ideal torque/rpm curve, but the current demands for high starting torque are a problem. The holy grail is a battery which has effectively an enormous surface to the electrodes without corresponding fragility, and so can be quickly recharged and discharged. (Traction batteries currently have a long service life but relatively slow charge and discharge. Starter batteries have a fast discharge for starting but are fragile and do not deep discharge well). Such a battery would completely supersede the inefficient compress air/decompress air cycle. So whichever compressed air tools division of this Korean manufacturer came up with this job preservation scheme - forget it and retrain as battery engineers.
Panurge has posted for the last time. Thanks for the positive moderations.
I can spot posts on the net at least from year 2000 about Mexico city running taxis and public buses on compressed air.
Am I missing the point ?
Z.
A completely compressed air vehicle has been made before and is a production model called the air car by a company MDI in italy. They have produced models for street use, you can see a video of it here.
...and it should be known by now
When an electric car is standing still the motor does not draw power. Converting energy expended while braking into compressed air has been done on normal trucks and busses for years. Converting the batteries stored energy into compressed air is gaurenteed to loose some of the energy in the conversion and therefore will not last as long. Every time you convert energy you loose some so it makes sense to save the wasted braking energy. There is nothing really "new" about this car except they have taken a common fuel saving technology used on heavy transport fleets and applied it to an electric car. If it works for an electric car it would work for a normal car but with electric cars you can't just get a bigger fuel tank.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
[ A hole in a compressed air tank equals instant explosion. ]
Err, no. A hole of any size equals a leak and a loss of pressure. I am not sure which science friction books (pun intended) you have been reading but I have suffered many leaks in high pressure air tanks and in only one case was it dangerous. That was when a friend dropped his tank on the side of the pool and the regulator valve broke off and the tank left the scene rapidly. The type of gas was irrelevant as any high pressure tank would have taken the same trip. Do you think we would be allowed to strap these things to our backs if they were as dangerous as you say?
Petrol vapour on the other hand is very explosive so even an empty petrol tank can explode.
I love stacking my barbecues in the shed at the end of summer - you can't beat a bit of grill on grill action.
One of the real dangers with current petrol engines is that they pump petrol to the engine at high pressure to meet sudden increases in demand (acceleration) and then pump the excess back to the petrol tank. This means that there is a lot of high-pressure petrol travelling around the car and when an accident occurs the risk of fire is much higher than 20 years ago.
On the other hand petrol tank design and placement has received a lot of consideration and is no longer such a danger as it was 20 years ago. So it is no longer the large tank that presents the major danger but the system itself.
I could not find a link but several years ago on the A40 in England there was a multi car accident in which most people died in the resulting fire rather than the crash. All the petrol gets dumped on the road and all the cars burnt. People could not escape in time especially those in the rear of 2 door cars.
Pressure of a propane tank at 100 deg F is 175PSI - this is a pressure that can be easily managed.
Take note too, that any major pressure loss on a propane tank will instantly drop the temperature of the remaining liquid in the tank (as it boils), resulting in less pressure - check a Pressure-Temperature chart for propane sometime.
Compressed air at a few thousand PSI is a lot more trouble to deal with in an accident.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
Someone mentioned the problems of having a (scuba) tank of compressed air sitting in the hot sun...yes, it can be a problem, obviously, if the air heats and expands above the pressure rating of the tank. I am assuming they thought of this and would make the tank adequately strong. (With scuba, the shop fills your tank to the limit, and then the hot sun gives you another 1000 psi and your burst disc goes. This is less than the five-thirds working pressure they push your tank to when they hydro it--I'm sure the tanks on the cars would have some kind of overpressure relief like a burst disc.)
The French air car article points out, "In the case of an accident with air tank breakage, there would be no explosion or shattering because the tanks are not metallic but made of glass fibre. The tanks would crack longitudinally, and the air would escape, causing a strong buzzing sound with no dangerous factor."
Well.
It's great to know that it's a carbon fiber tank so it won't turn into a screaming cloud of schrapnel, but isn't there another issue at work here?
Now, I don't know exactly where on that tiny car the tank is, but I'd assume it's under the seat someplace.
The volume of that car is what...two cubic meters? What happens when you instantly put 90 cubic meters of air inside it? (Or under it?)
Have a look at this rather larger car for an example. Look, ma! No fragmentation thanks to a steel tank, but all that air introduced to an enclosed space jiffy-pops a car like a cheap paper cup.
I'm more than willing to admit there's more to carbon-fiber tanks than I know. Maybe there's some property that prevents them from releasing all that energy in less than, say, 10 seconds, no matter how badly crushed. But I'm officially skeptical.
They say there's enough energy in a scuba tank to lift a hook-and-ladder fire truck 20 meters in the air. That's exactly the sort of energy I don't want released near me in a short timeframe. Gasoline is good in comparison because it doesn't tend to do this when the tank is ruptured.
Then again, a compressed air tank explosion might be just what I need to get ahead in today's Bay Area traffic. Up yours, Fastrak!
Yeah -- I've been watching this guy for a couple years, and have come to the conclusion that he's a complete con-artist.
If you read the website carefully, you'll note that the specifications he displays here http://www.theaircar.com/models.html for the various models (range, top speed, refuel rates, etc) are all based on theoretical measurements made by guessing how much improvement he can get from changing a number of things in his current design. The current design has been tested for a total of 7.2 km. He gets his 200-300km range by extrapolating based on his guesses. See http://www.theaircar.com/tests.html (scroll down to "Mileage comparison between the taxi in development and the final car") for the true specifications, and note that after the top row, they're all extrapolations. He's basically saying he should get x% increase from this change, and y% from that change, and that means the "improved" engine will get (x+y)% better performance.
His site hasn't changed in at least a year -- meaning those figures haven't been updates with actual test results, and I don't think they ever will be. It's real easy to guess how much improvement various changes may make. It's not so easy to get that improvement out of them.
Next, note that he's selling "licenses" to build factories to produce the car. This is his real goal: Grab some $$ from investors before they find out he has no real product. He's a lot like the guys selling free energy based on concepts that violate the laws of thermodynamics, but will have a working model "real soon now".
Go ahead and watch this guy -- it's entertainment at least, -- but don't give him any of your money until he can back up his specifications with real world tests.
Help find a cure for Gidget.
25 km/h = 15.625 mi/h, not 40 mi/h
Guess someone goofed up on the metric system once again :)
Neocons are children who don't want their toys taken away, and won't clean their room because it isn't fun.
Thank you for recognizing that the distinction between the present domanant "neo-conservative" group think party in the US and true conservatives. True conservatives wouldn't have bought the toys in the first place (we're compulsive savers) and wouldn't have let the room get messy for fear of unspecified adverse consequences. True conservatives (I know, I am one) are more likely to avoid doing things because they are fun (on the principle that the more atractive the lure, the more likely it is to be bait).
--MarkusQ