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The Air Car Nears Completion
torok writes "According to an article on Gizmag, Tata, India's largest automotive manufacturer, has developed a car that runs on compressed air. It costs less than $3 USD to fill a tank on which it can run for 200 to 300km. The car will cost about USD $7,300 and has a top speed of 68mph. About once every 50,000 km you have to change the oil (1 liter of vegetable oil). Initial plans are to produce 3,000 cars per year."
According to an article on Gizmag, Tata, India's largest automotive manufacturer, has developed a car that runs on compressed air.
Well, if you eat a lot of Tandoori, this is a great use for that compressed air.
The theory of relativity doesn't work right in Arkansas.
Did half-life 2 teach us NOTHING about the dangers of compressed air cannisters?
Mexico has been using this tech for several years now, though this is a bit smaller than the taxi vans.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
Browse at -1 to keep an eye out for abuses.
this looks like the ultimate in vaporware, an as yet unavailable vehicle and runs on "air" might as well run on magic aether or unicorn blood. you can't even see air. pfft.
IC engines generate a lot of waste heat that can be used to warm the passenger compartment with little additional cost. On the other hand, IC vehicles need complicated a power hungry air conditioners to cool the passenger compartment during hot weather.
The compressed air powered car operates the other way around. Compressed air cools as it decompresses. The exhaust from this vehicle is below zero Celcius. That cold air acts as free AC. A heating system for a vehicle like this is going to be very expensive from a power consideration.
If these vehicles are not a scam then I think we can expect their adoption only in warm climates. In cold weather, I would not be surprised if the decompressed air freezes the components that transfer power to the wheels.
Seriously, how many brilliant inventions have we heard of lately, and how many of those vanish just days after being announced?
What about the far greater number of brillant inventions that vanish before we ever hear about them in the first place?!?!
If you are going to play the paranoid lunatic, aim high. There is no market for half-assed tin-hattery.
2-3 hundred kilometres - that's long downslope.
Squirrel!
So.. it costs like 5-10$ to fill a single scuba tank. Where do they get their $1.50 figure from? There is no mention of how that figure is arrived at at all.
:/
Running a two stage compressor for 3-4 hours will probably cost more than $1.50
And "Zero-pollution"? Can we have some truth in advertising please? Using the car causes pollution, plain and simple. Maybe it's 1/10th or maybe less of a petrol car but at least be honest about it and let us know exactly how much pollution it does cause. It's certainly not 0. Saying so leads to people assiming that this is some kind of crank.
Contrary to popular belief, coding is not all free blow-jobs and beer. Those things cost MONEY!
Brilliant ideas are a dime a dozen. Brilliant ideas which are economically and realistically feasable are a completely different story. Then, you have to match the person with the brilliant, feasable idea with someone who can make the business actually work. If you don't have all of those in place, it's a guaranteed failure.
Oh, you're not stuck, you're just unable to let go of the onion rings.
So could Washington, D.C. Plenty of hot air there!
The French guy who invented the car has been working on it for years. The car has been announced several times before and they are able to produce working prototypes. This counts as one of those technologies that is almost there but there is some small, pesky, won't-go-away, details that keep it from being economic. In that regard, it is similar to the plant that converts turkey guts to oil. The process works but isn't quite there.
The best thing about this car is that air-conditioning is very easy and costs no energy. As the air decompresses in the engine, it cools off. Directing that air into the cabin would provide air-conditioning with just about no effort.
If this actually comes into being, there are some really neat side-benefits of this sort of thing. Principally, as compressed air is not only easy to generate, it can be generated *AND* stored locally. That means that it can be done via "renewable" energy (solar and wind) *as they are available*.
As electricity is easy to generate locally - but not easy to store in sufficient quantity - you can't really have solar panels that will always be available to charge your electric car. However, you *can* have solar panels which fill your compressed-air tank, and then refill your can whenever you need.
Overall, that means a completely petroleum-free energy source for cars. Even if you don't believe that man is behind global warming, the thought of removing most of the automotive-produced pollution has got to be an appealing thought, with the idea of never paying a utility company (gas OR electric) to refuel your can again as a nice bonus.
Oh, you're not stuck, you're just unable to let go of the onion rings.
You know, I'm starting to get the idea that it really WOULD kill the editors to actually edit something. This is of course proof that the Firehose cannot make up for the failings of idiot editors.
Now, if there were no links in TFA, then torok would have an excuse for not knowing that this vehicle was actually developed by Moteur Developpment International, or MDI. If you visit their site you can read MDI's press release about their deal with Tata. But in fact not only the technology but the entire vehicle was designed by MDI. Not only have they been using them in Mexico (Mexico City is the most polluted city on the planet) but they've been using them for some years in Spain.
Shame on you torok, and shame on you ScuttleMonkey. The former for falsely attributing the vehicle and technology to the undeserving; the latter for not doing his job and checking the story for validity.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Uh, yeah, it is.
Burning fossil fuels in a power plant is generally more efficient and cleaner than burning them in a small, light mobile engine. So it reduces pollution that way.
While compressed air isn't the only such storage medium that turns the vehicle-power problem into a large-scale generation problem, batteries and fuel cells are far from clean to produce. Compressed air canisters aren't nearly as dirty. And, its a lot easier to build a distributed compressed-air generating infrastructure powered by large-scale power plants than it is for hydrogen.
Its not solving everything, but if it performs as advertised, it certainly is a useful part of the solution.
I'd like to see how this car does in crash testing. Sure, it's easy to make a light-weight car that can be pushed around with some compressed air, but designing one that doesn't kill all its occupants the first time it hits someone walk across the street, let alone a Hummer, is a bit trickier. Where is this car going to be produced? India? I somehow doubt the safety standards are all that high.
300 liters of 200 bar air has an energy content of about 35MJ or just about the same as 1 liter of gasoline. Even giving some credit for higher (perfect?) efficiency and some energy recovery through environmental heating, it seems to be a stretch to suggest that any reasonable useful car could run 2-300 miles on this. Actually, the energy content is probably a bit lower since they'll need some overpressure to run the engine (maybe 50 bar or so?). And I don't really want to be sitting in the car when they fill it. The heat generated by filling the tank is pretty much equivalent to burning a quart of gas in the trunk.
[humor]Yes, I am kidding, there are ways to alleviate the heat generation like compressing outside, slow filling,...[/humor]
While I agree in principle, I'd be interested in the assumptions you used to reach that conclusion (e.g. how much energy it takes to move the machine a km).
The amount of energy needed to move a person that far is not that much. An average cyclist can produce something like 3watts/kg. A 75kg cyclist produces something like 225 watts; assuming he can travel at about 20km/h, we can put a lower bound on the energy needed to move a typical person 200km at 2250 watt hours.
Let's assume we have an engine that is as efficient as the rider (for setting the lower bound) and weighs as much as the rider. Lets suppose that we need twice the energy to move engine and rider the 200km. So we need 4500KWh.
Assuming that electricity costs $0.10/KWh, then such a machine would consume forty five cents to move a person 200km.
To put it in perspective then, the claim is that this car can move a person from place to place using only fourteen times the energy a reasonably fit cyclist would use.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Actually, there's no big conspiracy. Inventors are not disappearing. There are generally three reasons why you'll hear about it then nothing else:
/. will post very "first announcement" kind of things. The actual product is years or decades away from the market, and thus there's not a lot to be said.
/.'s rather short attention span (I mean really, how often are there good followups here?) and that's what you get.
1) It's all hype, no substance. There are plenty of inventors that try to hype things to get capital that they really have no idea how to make work. Sometimes they are even out and out frauds.
2) The product is a long way off. Often
3) The product doesn't do as well as expected. Some things sound really cool and then just don't pan out. They go to market and flop.
Take any one of those and combine it with
So get some perspective, and save the aluminium for wrapping leftovers.
Those are some bodacious Tatas.
Damn. I read that headline and thought my flying car was almost ready.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
Take $0.10 per kW-hr. A kg of gasoline has around 42000 kJ, or about 10 kW-hr (1 kW-hr = 3600 kJ) (I'm rounding horribly for simplicity, but it's not going to change the analysis much). A gallon of gasoline has about 2.5 kg of liquid, so that's about 25 kW-hr. Assuming similar efficiencies as gasoline - not unreasonable considering compression of air is typically adiabatic but then stored so you bleed out a lot of energy as heat (insulation to keep that energy would be heavy). So 10 gallons would be about 250 kW-hr. At $0.10 a kW-hr, that means about $25 in electricity. So, to get down to $3 a fill-up, you'd need something that's about 8x the thermal efficiency of gasoline, or something that is quite microscopic so doesn't have much drag. Considering you can't get 8x the efficiency of gasoline (it's already between 20% and 30%), I don't see a fill-up costing $3.
That said, $25 a tank is very comparable to gasoline, so it's probably reasonable.
However, my requirement for alternative fuels is still 400+ miles (note 200-300km from the article is only 124 to 186 miles) on a single "charge", and able to get a complete charge in 5 minutes, for $30 or less, with no nominal increase in vehicle cost.
Other than that, I don't really care what the technology is...
"There are a dozen opinions on a matter until you know the truth. Then there is only one." - CS Lewis (paraprhase)
If you are going to play the paranoid lunatic, aim high. There is no market for half-assed tin-hattery.
But if there's a market for half-tinned ass-hattery, then I'm set!
The enemies of Democracy are
BTW, the tanks are the real problem. Cheap, light, strong, pick any two. :-)
-Jay-
Compressing air probably involves combustion-engine driven air compressors, so I don't see the real benefit here.
"probably"? You're writing off this entire technology because of a "probably"? News flash: energy can be converted from one form into another and stored in innumerable ways (and with only moderate loss according to efficiency physics and such). i.e. You can compress air using whatever the hell you want. The local hardware store has a compressor that runs from a wall outlet. With enough solar cells you could power that outlet. You could do it up to a point by hooking up a damn bicycle to an air pump for christ sake.
This technology takes one problem and converts it into another problem, namely how do we get compressed air without creating emissions. Pretty much everything we learn from science is based on the idea of converting one problem into another one we can solve.
Pesky kids let the air out of your tires, just fill em back up with your fuel... or run out of fuel, fill from your tires.
Thermodynically you're correct. Enviromentally you're correct. Economically and politically you're wrong.
For the forseeable future we (the US) will be getting 55-60% of our electricity off of coal and 20% off of nuclear power. This electrical power can, with this compressed air model, be used to power the whole transportation sector, instead of oil. The US is the "middle east of coal". That means more US money staying in the US, less money being pumped into a volitale part of the world that doesn't like us much, more US jobs, more US oversight of the involved companies. As an American this benefits us greatly. It benefits all Americans except for the CEOs of the top 5 or so oil companies. (This applies elsewhere too, but America has the most cars, generates the most pollution from them, and all in all is the biggest oil consumer; though China is close, maybe surpassed the US in the past year or so.)
Additionally one would assume that the air compressors would be run off of electric motors, which allows them to use electricity produced anyway they want. If you wanted to use solar panels at home and plug the car into a small compressor to recharge that would work. If you wanted to goto a service station and buy their compressed air, that would work too. Unlike hydrogen, air compressing equipment is already widespread, hydrogen production isn't there yet. Either way, you're right in that we get less out than we put in, but the transision from oil to will be like that. We are very very unlikely to find something else we can pump out of the ground and use as easily as oil.
We are now transisioning permantly from a primary portable fuel (oil) to a secondary (compressed air, hydrogen, batteries, etc). It seems that these next fuel(s) will be with us for atleast the 100+ years oil has been.
Mike Scanlon
If you have ever been to India you can see that this is infact a great idea. It sucks for America, sucks HARD, but Indian strees are swamped with three-wheeled-pull-start-lawnmower-powered Rickshaws and the air is noxious. These cars would be an excellent replacment for those and taxi companies could use the GPS features to the benefit of all. Not every invention has to only solve problems you know about to be good.
... awesome.
The smog laws in America are almost pointless when you consider it's GLOBAL warming and India/Mexico are basically shitting into the atmosphere. If they can make this work
Yes, and it's a good idea to embiggen your vocabulary at the same time.
"I've got more toys than Teruhisa Kitahara."
[..] It takes about 9.8 Watts to move one kilogram one meter in one second. [...] 27.4 kW * 12.5 hours = 343 kW-h.
Congratulations! You just calculated how much energy you need to lift the car to an altitude of 250 km (!)
Do these things go faster than light? It's the only way I can explain the fact that the first post is modded redundant.
Cogito, ergo sig.
Head on over to USPTO.gov, and show me the invention that solves the energy crisis.
How about this?
You just need to find a way to harness the cat's kinetic energy in a usable form.
A legparnasom tele van angolnaval.
I need to embetter my dictionary then, I thought that embroaden was a perfectly cromulent word!
If you don't know what AltaVista is (was), get off my lawn.
lift it, wait for the earth to rotate, put it back down.. you can probably pick up some regenerative braking energy on the way down.
It's sad that one can actually secure a patent on something like that.
-Jay-
The other thing that this "supressed technology" conspiracy fantasies ignore is the fact that there is no monopoly on cars.
... had a way to offer a vastly better product than their current product line, you'd better believe they'd do it as fast as they could, because that's the way to make money.
No, there is something much more effective. It's called High Barrier to Entry, and it is extremely effective at keeping out small car manufacturers, with expensive safety tests and regulation compliance (read, lawyers fees) etc (basically all of the lame attempts by American auto manufacturers to keep the Japanese out of the American car market by corrupting the political process). Unfortunately, the Japanese were smart enough to change their manufacturing process fast enough to keep up with the regulatory changes, and had the financial fortitude to push on through the pain.
If GM
Bzzzt, wrong, but thankyou for playing. The way to make money in the car business (like any other) is to make sales. In GMs case they do this through a dealership network. The dealership network makes almost no profit from the initial sale of the car, and nearly all of the profit through service and maintenance, in which they sell small products at ridiculous markups. When GM trialled the EV1, the dealerships realised that an electric motor has very little maintenance costs, and so there was no profit in selling them.
Second, to make cars requires a large investment in manufacturing equipment. Billions of dollars in fact. This investment is amortised over a long time horizon. If you radically change your manufacturing process to produce a better car, you lose your investment in the current equipment, something no CEO is going to be willing to explain at the next shareholder's quarterly.
There is more to business than just product.
- Nothing to see hear.
I think the original poster meant this particular usage of the term "Dutch Oven":
A practical joke involving flatulence underneath a blanket or cover inspired by the mechanics of the "Dutch Oven".
Let's do the math, but starting from different angle. Really cheap electricity is $0.10/kWh, and the fuel station will probably charge a 30% markup at a minimum, for $0.13/kWh. For $3.00, if the air compressor is 100% efficient and there are no resistive losses involved with charging the tank, and you charge it at constant temperature you can store 23kWhr. In reality it would store less because the air would heat up as it compresses, then cool down after you leave the pump. The pressure would drop as it cools, so you'd be paying for pressure that you never get to use. The most fuel efficient cars today are hybrids that get 70mpg under very favorable conditions. Gasoline has 34.6MJ/liter (http://en.wikipedia.org/wiki/Gasoline), so if the Prius is 48% efficient (http://www.uwgb.edu/dutchs/EarthSC102Notes/102Ene rgy.htm) it will take 70mpg / 34.6MJ/l / 48% * 3.785gal /l * 1.6km / mile = 25.5km/MJ . With our cheap power, that comes out to 25.5km/MJ * 0.278 MJ/kWh / $0.13/kWh = 54.6 km/$ , or $5.49/300km . So expecting to travel 300km with only $3.00 worth of fuel would require you to invent a 100% efficient compressed air powertrain, get really cheap power, and double the efficiency (post-engine) of modern cars. Not bloody likely.
We can also calculate the pressure and maximum size of the fuel tank if we remember that PV=nRT and W = integral(P, dV). Solving for constant temperature charging gives W = nRT_initial - lnV |(V_initial - V_final) . Traveling 300km with the above figures requires storing 11.76MJ. I get 24.8m for the maximum tank size that would still be high enough pressure. But that's bigger than the car. A 50 gallon tank is probably about the biggest you could fit in that tiny car, and this would be only 0.187 cubic meter. Such a tiny tank could theoretically store 56MJ. If that is indeed their tank size, then the car might actually work with realistically efficient parts. But from Boyle's law the pressure would be 500atm!
You're right that they can't really stop you from selling it. But they can convince legislature to pass laws to prevent your vehicle from being considered road worthy. They can launch a propaganda campaign, make your product look bad, and run you out of business. They can buy up your engineers, your management, heck, even enter into contracts with your suppliers. Think about all the dirty little tactics that Microsoft used, then add politics to it. Like for example, convince some lawyers to sue your product for every little defect. Or convince legislature to tighten the regulations for your product--for your parts supplier, your resource supplier, etc. Conspiracy theory? Maybe. But most of these tactics have been used before. And there's nothing preventing big companies from using them to kill off competition.
Why is ethanol so popular these days as an alternative fuel as opposed to other green fuel solutions? Ethanol is only a small (albeit a significant) step away from oil, yet it's being touted as the fuel that will save the planet. It's because corn farmers have a huge presence in DC. They saw an opportunity to increase the worth of their crop, and they jumped to get legislatures' attention. Don't ever underestimate the power of lobbying.
"If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
Compressed air is not a power source, since the energy has to come from some other source, such as electricity. Storing energy as compressed air is not a more efficient process than storing electricity inside a battery. There ARE electric cars today with more range than the Air Car. And they are not all ultracompact cars but some more reasonable formats. So we have already a technology that is simpler, proven, has better performance, it is likely to be much more reliable (fewer moving parts) and has constant performance (a vehicle run by compressed air will lower its performance as it runs out of "gas"). I'm not completely sure it is cheaper today, but it certainly will be as batteries progress (they have been progressing at a steady 10% increase in capacity or decrease in cost every year for the last few decades, it is expected that the trend continues). The Air Car is not so proven, and the manufacturing costs will surely go up as they near production (they always do). I'm not saying this project has no value, but investing the same money and effort in developing electric cars will certainly produce better results faster.
iso = same
thermal = temperature
isothermal = same temperature
With isothermal expansion and compression, the temperature doesn't change. The process is inefficient to the extent that the temperature does change; so the trick is to keep that from happening.
Here's a quote from http://en.wikipedia.org/wiki/Gas_compressor
""Charles's law says "when a gas is compressed, temperature is raised". There are three possible relationships between temperature and pressure in a volume of gas undergoing compression:
* Isothermal - gas remains at constant temperature throughout the process. In this cycle, internal energy is removed from the system as heat at the same rate that it is added by the mechanical work of compression. Isothermal compression or expansion is favored by a large heat exchanging surface, a small gas volume, or a long time scale (i.e., a small power level). With practical devices, isothermal compression is usually not attainable. For example, even a bicycle tire-pump gets hot during use.
* Adiabatic - In this process there is no heat transfer to or from the system, and all supplied work is added to the internal energy of the gas, resulting in increases of temperature and pressure. Theoretical temperature rise is T2 = T1Rc((k-1)/k)), with T1 and T2 in degrees Rankine or kelvins, and k = ratio of specific heats (approximately 1.4 for air). The rise in air and temperature ratio means compression does not follow a simple pressure to volume ratio. This is less efficient, but quick. Adiabatic compression or expansion is favored by good insulation, a large gas volume, or a short time scale (i.e., a high power level). In practice there will always be a certain amount of heat flow, as to make a perfect adiabatic system would require perfect heat insulation of all parts of a machine.
* Polytropic - This assumes that heat may enter or leave the system, and that input shaft work can appear as both increased pressure (usually useful work) and increased temperature above adiabatic (usually losses due to cycle efficiency). Cycle efficiency is then the ratio of temperature rise at theoretical 100 percent (adiabatic) vs. actual (polytropic).""
Well obviously, dumping a few heavy metals into the environment is preferable to releasing more CO2 into the atmosphere. I'd rather have mercury poisoning than live in a world that's a few degrees warmer. ;)
IIRC, the advertised MPG were maximum values, which I have heard are achieved from time to time. It really does not matter, though, because Detroit is still pumping out cars with <20MPG gas mileage. Even the Prius' worst case scenario doubles that figure. So, while it is not a solution to the problem, it is certainly a step in the right direction.
As for the pollutants in the batteries, you certainly have a point. Compressed air is certainly better than battery acid for the environment. Either way, anything that makes individuals less reliant on petrochemicals has to be a good thing.
All data is speech. All speech is Free.
Go read your WWI history, and spend 10 minutes contemplating the meaning of 3 million dead or permanently maimed, and 3 million more wounded. Six in 10 men between 18 and 28 dead or permanently maimed. Consider Verdun, and just how tough that going was.
FFS, I'm not supposed to side with the French. I'm English. But this meme sickens me. A way of insulting the French for acting in what they perceive to be their national interest, when that does not coincide with what the US considers its national interest (and let's be very clear that the US only ever acts in what it considers to be its national interest), it just shows the originators and all those who parrot them as breathtakingly arrogant and ignorant.
And I suppose that you somehow think it's OK for you to make a general statement like this, but it's not OK for those in the US to make general statements about the French. Let's be perfectly clear here. Although the US avoids acting in ways that are contrary to its national interests, it frequently makes decisions and acts in ways that have no impact one way or the other on national interests -- just like pretty much any other country. The US has been, and continues to be very generous in many ways. Although some of that generosity has political aims, certainly not all of it does. I think you need to take a serious dose of your own medicine, lest you yourself be misconstrued as arrogant and ignorant. For what it's worth, I've heard pretty much the same joke come from the colleagues in England and Germany that I work with on a regular basis. Does that make it right? No, but it does show that US-bashing isn't the answer to the problem. Start at home and work your way outward.
GreyPoopon
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Why is it I can write insightful comments but can't come up with a clever signature?