100-MPG Air-Powered Car Headed To US Next Year

An anonymous reader sends us to Popular Mechanics for word on a New York automaker with plans to introduce a US version of the air-powered car, with which India's Tata Motors made a splash last year. Zero Pollution Motors plans a sub-$18,000, 6-passenger vehicle that can hit 96 mph and gets over 100 MPG, using an untried dual engine — the air-powered motor being supplemented by a second (unspecified) engine that would kick in above 35 MPH. The company estimates that "a vehicle with one tank of air and, say, 8 gallons of either conventional petrol, ethanol, or biofuel could hit between 800 and 1000 miles." The vehicle could be introduced to the market as early as 2009.

Comments

But..

[somersault]

What happens when we run out of air!??!??

Re:But..

[eln]

I would have thought the emergency Air Supply would be provided via a recording of "All Out of Love", but I guess that might make it more desirable just to stay stranded by the side of the road rather than trying to use it.

Re:But..

[Sandbags]

From what I can research, the air tank will power the car, all by itself, for about 200Km. With a gas engine suppliment, this could be drastically extended, upwards of 400Km I would say is a fair (safe) estimate. The cars come with their own internal pump system that can run off household electricity, but it takes upwards of 4 hours to fill the tank, and assuming it operates like any other air compressor, it will be loud. The good news is high pressure canisters could refil your tank in 3 minutes or less. Houses would almost certainly have to be equipped with high pressure home filling stations. they won't take much room, could fill 2-3 cars at once, and given all day to refill. By burying them we could eliminate most of the noise. The heat generated compressing the air could even be used for hot water (or to supplement it) as a side effect.

Creating high pressure air (4000+ PSI) generates heat. Filling a tank with uncompressed air takes time almost as much for safety as for the actual time to compress. Filling stations could bury high volume, high efficiency compressors, divert the heat using geothermal options, and eliminate the bulk of noise. You could fill up in 3-5 minutes by using pre-pressurized air from massive underground tanks, or even massive above-ground tanks in some areas. they'd cost a bit to install, but over 10 years would pay better returns than fossil fuel stations. At home, if you had a smaller version system, you could either make hot water, or put in geothermal capacitors. The benefit to geothermal would mean in some markets you'd never have to shovel your walkway in the winter again (use heat pipes under concrete to both dispurse heat and melt snow, lol)

It's a bit dangerous though... carbon fiber tanks at 4000+ PSI... If one ruptuers, the force released could quite litteraly throw the car a few blocks. More likely, it would simply rupture, causing the car to act like a bomb, just without flames... Vapor expansion at this level could rip people and metal apart. these tanks need to be REALLY strong to be safe, adding significantly to vehicle weight, reducing storage space, and limiting fuel economy. Sure, we can make one that goes 800KM on a fill up and has room for 4 including luggage, but there's no way the motor safety guys are ever going to allow it on the streets...

I'm skeptical. Keep them out of my country until there's 50,000 or more of them driving around. We'll see then how safe they are.

Also, the vehicle itself is pollution free, but making the electricity to compress the air isn't. If we're moving in this direction we'll need a major investment in free energy sources like solar and wind. Also, compressing the air locally at filling stations requires power. a lot of power. We'll need a super conducting grid to make that happen (if we plan to use clean electricity instead of current local poewr plants). Of course, the same is true for electric cars.

High pressure air can be trucked around easy engouh too. We don't have to make air at every filling station. We could have a few small locations around town and drive trucks from key points to filling stations. This may lower the cost and complexity a bit in favor of logistics.

We'll wait and see.

Re:But..

[Rei]

Autobloggreen has garnered a number of comments on this concept, most of them negative. To sum up:

* The thermodynamic efficiency of air cars is worse than gasoline engines, often far worse, meaning that you *hurt* the environment by driving it.
* The overwhelming majority of the performance of this vehicle comes from gasoline, not air
* The company has a very bad reputation of making ludicrous claims and misrepresenting stats
* It's made by Indian manufacturer Tata motors, not known for quality

In short, don't bother. If you want an affordable (100 mile range without burning any gasoline, that will be on the road in a year or two, there are really three good options I can think of off the top of my head right now: the Aptera, the VentureOne, and the MiEV. The Aptera is for if you want the absolute limit in energy efficiency modern tech can currently provide and want to look like you're driving a spaceship, the VentureOne is for if you want to feel like you're driving a motorcycle, and the MiEV is for if you have more than two people. I've probably missed a couple other good options, I'm sure.

To potential EV buyers: keep an eye out for scammers. Two big ones are LionEV and Spark EV.
To potential hydrogen car buyers: hydrogen cars are worse for the environment than gasoline cars, so don't bother.

Re:But..

[Rei]

[quote]It's emissions, not waste heat, that are why gasoline engines are bad.[/quote]

CO2 emissions per mile are proportional to thermodynamic efficiency of the fuel cycle and amount of energy that is needed per mile. With a gasoline car, the well-to-wheel efficiency is about 20%. With an electric, it's ~30%. With a hydrogen car, it's ~15-20%. With an air car that operates on air alone, it's something like 4-20%, depending on whether you're using an onboard or home compressor, or whether you're using a huge, expensive, top of the line regenerative industrial compressor.

Air cars have a whole host of other issues, too. Horrible volumetric energy density, safety (the energy likes instant releases), decaying performance (the lower the tanks get, the slower your car), and so on.

Re:But..

[Sandbags]

The energy used at the power plant 1) is far less than individual engines in terms of energy input to output, 2) can be mitigated by reclamation, scrubbing, and other means, 3) can be from 100% free energy (solar, wind, geothermal, etc, and hopefully 100% or more of what we're adding to the system will be just that), 4) can be done cheaper, and with less logistical issues, 5) doesn't have seccondary environmental issues from ground seepage, leaks, etc, 6) doesn't require transporting across the country on trucks, 7) you get the idea yet?

Re:But..

[Rei]

Air powered engines have extremely high (over 90%) efficiency

And compressors have extremely *low* efficiency. Small compressors (like you'd find onboard or in a garage) are 10-15% efficient at best, while huge, massively expensive regenerative industrial compressors can only get up to 60% or so.

The energy to make air into a compressed form can be done with 100% renewable energy.

Same with electric cars. And they don't have the massive compression losses of air cars, and they have, even currently, much higher volumetric energy density.

It's like an electric car, except instead of the electric motors gettign about 70% efficiency

Try ~90%.

Also, the thermal rediation (heat) from compression can be used to create hot water,

Hence the term "regenerative". Unfortunately, Carnot sticks his ugly head into this process.

Also note the energy to compress air is about 5 times less than the energy input to product H2 to power a fuel cell vehicle the same distance.

And you get this silly claim from where?

Re:But..

[Plekto]

You forget, though, that the batteries cause much greater environmental damage and recycling issues, plus weigh a LOT more. Air compressors are horrible for efficiency, but they are also capable of running for decades without much upkeep as well as there's no real need to replace them for the life of the car.

Typical home fueling stations for CNG or electric and so on(if you add in the batteries to the equation) add a huge cost up front. A couple of large air tanks, OTOH, aren't much more complex that a typical SCUBA tank.(few hundred dollars of the car's cost, each)

Mythbusters shot propane tanks with handguns in a recent episode and they dented but didn't puncture the tank. That's very strong, indeed. Smash Labs tested Rhino Lining versus an explosion and the thing survived. Put the two together and you can easily vent any escaping gas away from the passengers *if* something actually manages to puncture the tanks that doesn't already kill the passengers outright from the impact.(we're talking hit by a train crash or similar to puncture the tanks)

$4000 in batteries that you pay $5000 for in a Prius add up to a long payback time compared to a less expensive air powered car(or even a typical Corolla or Fit or similar small car)

Re:But..

[Rei]

Wind, water, and solar plants may have low efficiency for turning energy into electricity, but the energy required to do that is free, unlimited, and does not directly pollute, so therefore is irrelevent.

Wrong. *Nothing* is irrelevant. Wind and solar have huge capital costs relating to all of the mining, processing, and labor that goes into them. Think giant towers of steep pop out of the ground without extensive mining and very dirty smelting operations, for example? The environmental cost of wind and solar is certainly notably lower than coal, but it *is* relevant. They also take up land that could otherwise be wilderness (especially solar, which can't pair with farming like wind can).

Hydro ("water") is the worst. It takes up huge amounts of land -- often ten times as much as the equivalent amount for solar generation in a sunny location. It destroys what are often some of the most scenic and environmentally sensitive areas in a country. Consider the Xolorado, for example -- an aquatic oasis in the middle of arid lands that used to even have otters living in it before we dammed the heck out of it and destroyed canyon after beautiful canyon. And to top it all off, *hydro causes global warming*. Hydroelectric plants lead to organic matter decaying anerobically instead of aerobically, which means methane, not CO2. Methane is a far worse greenhouse gas than CO2.

Efficiency ALWAYS matters.

I'm NEVER going to suggest we use coal or other fuel to compress the air for air cars, nor would I for electric cars either

It's better for the environment to run an electric car from coal electricity than a gasoline car burning gasoline. By a good margin. It's notably *worse* to run an air car from coal power.

The direct efficincy of stored energy to engine power is near 100% for air cars.

~90% or so. It's getting the energy stored that's the problem -- 10-15% efficiency from garage or onboard-scale compressors.

Your numbers on electric motor efficiency are also WAY off. Yes, motors can operate at those efficienies, but only under constant and predictable (ideal) torque and RPM. In the field, they almost never come near those ideals. They do much better (60% or so efficiency for electric

Sorry to be blunt, but you simply have no clue what you're talking about. Start reading. The most efficient electric motors are about 95% efficient. 85-90% is more typical for an electric car in standard driving conditions.

combine this with distance loss of poewr over high voltage lines

A) Air compressors have the exact same loss.
B) Once again, you demonstrate your ignorance. In the US, transmission losses are only 7.2%.

battery charge loss (heat when charging)

0.1% for li-ion.

battery depreciation (loss over time)

Virtually none with modern automotive li-ions (nanophosphates, titanates, spinels, etc).

and discharge loss (bettery efficincy)

Also 0.1% (see above link).

the other problems with electric cars are safety

That's funny coming from an air car advocate, given that compressed air has the fastest energy discharge in disaster conditions, faster than even hydrogen.

LiIon batteries explode

Automotive li-ions (titanates, nanophosphates, spinels, etc) do not.

capacitors can kill instantly

So can an exploding air tank. Both are "accident situations", but the former requires either new laws of physics or the casing to break and move out of the way, all of the engine components between it and you to move away, terminals to suddenly run into you or something you're sitting on, all without the fuses melting.

they're complex and expensiv

Re:But..

[Rei]

You forget, though, that the batteries cause much greater environmental damage and recycling issues

Myth. Lithium-ion batteries are traditionally made from nontoxic lithium carbonate (often used in ovenware), nontoxic cobalt oxide (used as a pottery glaze), nontoxic graphite (used in pencils), and a polymer (plastic) membrane, all with a nontoxic electrolyte. You're mixing up lead-acid and nickel-cadmium batteries with more modern NiMH and li-ion batteries.

Car batteries are the most successful recycling program in modern history. Almost every car battery on the road today is ultimately recycled.

plus weigh a LOT more.

Much of the added weight is offset by reduced engine mass, since electric motors are so much smaller and lighter than piston motors. The Aptera Typ-1e, for example, weighs just 1500lbs. The MiEV and VentureOne are similarly lightweight.

Air compressors are horrible for efficiency, but they are also capable of running for decades without much upkeep as well as there's no real need to replace them for the life of the car.

You're telling me you've never had a compressor break? Are you kidding me? I've had the compressor on my AC break *twice*, and the compressor on my refrigerator break once. Compressors operate in high-stress environments, whether they're compressing coolant or compressing air.

Typical home fueling stations for CNG

Who's talking about CNG?

or electric

It's called a "plug" and an "outlet". Put plug in outlet. You're charging! The Aptera, for example, charges on an ordinary 110V/15A household outlet. The MiEV has multiple charging options.

A couple of large air tanks, OTOH, aren't much more complex that a typical SCUBA tank.

A scuba tank won't destroy your house if it has manufacturing defects or corrodes with age.

$4000 in batteries that you pay $5000 for in a Prius add up to a long payback time compared to a less expensive air powered car

The MiEV is something like $23-$24k. The Aptera is $27k. The VentureOne is something like $20k. And these are made in *first world nations*, unlike the $18k air car made by infamously low quality Tata Motors in India. And unlike the air car, they don't, well, destroy the environment worse than driving a gasoline car.

Re:But..

[Rei]

First off, reserves don't work that way. Here's a writeup concerning how this concept applies to oil, but the same thing applies to lithium. Reserves don't simply "run out"; there's many thousands of cubic miles of the stuff in Earth's crust and oceans (Earth's 1.65e23kg crust is 20-70ppm lithium for a total mass of 3.3 to 11.6 quintillion kilograms). All that changes is how much is mineable at *today's prices* with *today's technology*. I.e., either higher prices or advancing technology put more lithium into play -- and not just a little more, but literally exponentially more. Example: the oceans have And on top of this, unlike oil, lithium is an easily displaceable resource -- most lithium is used in glass, ceramics, and greases, and can be substituted for in all of them.

The scare articles ignore these basic facts. They also ignore other things inconvenient to them -- most notably, tailings. For example, listen to this quote:

"This means there is less lithium per volume of water, so competitors have to process more water, explained Tahil, adding that there is also the issue of the lithium-to-magnesium ratio. The more magnesium, the harder it is to extract the lithium."

Yes, but that means that you get *more magnesium* out of the process, which also has sales value. Likewise, other mining operations that are seeking various minerals can (and do) get lithium tailings. Currently, these are typically discarded due to the low price of lithium. As demand for a mineral rises, recovery circuits get added where appropriate. This is "value added" mining -- no new mining is going on, but you just get more product out of it. Production from almost any brine pond in the world will give you lithium tailings, but almost none bother to extract the lithium salts from them; they're going after other, currently more valuable minerals.

Some people have this silly notion of world mining operations as though the Earth was some big ball of "nothing" in the crust, and scattered around this "nothing" are little random deposits of one mineral (mixed in with "nothing"), and these couple deposits are all there are of that mineral. And, obviously, the real world doesn't work that way. *Everywhere* is minerals, and a given element can be found almost anywhere at least in *some* concentration, however minimal. All that changes from place to place is how cheap it is to extract (which can vary widely). Likewise, when you produce products from anywhere, you're going to get tailings that include all sorts of other minerals -- and you're mining, crushing, and concentrating them to boot, so half of the work is already done! But if the price of the minerals is low, it's not worth recovering further from the tailings. If the price rises, you recover them; it's as simple as that.

One thing to remember about lithium: it's cheap. It's currently very cheap. So? Well, people don't prospect for cheap minerals. Think for a second of how much oil our insatiable demand has continually turned up over the past century. Now imagine actual exploration for valuable lithium deposits. It's only reasonable to expect major growth in known lithium reserves, probably by orders of magnitude, should lithium suddenly gain any appreciable value.

Lastly -- and here's the real kicker -- lithium is only a tiny fraction of the cost of a lithium ion battery It's price could grow tenfold and you'd barely even notice it (and you better believe there'd be a *lot* of new reserves coming online with that much price growth!) 1 kWh of automotive li-ion batteries currently costs ~$300-$2000, depending on the type. This involves less than a kilogram of lithium carbonate, which currently costs about $4.50.

In short: Ignore the scare mongering. There's no world shortage of lithium, and never will be.

Re:But..

[Rei]

Wrong again. Almost all car companies looking at li-ion are not looking at conventional "laptop batteries", but the alternative chemistries that sacrifice a little energy density in exchange for a very long lifespan and a high degree of safety. These include phosphates, titanates, spinels, etc. You can generally even shoot these battery packs with no fire occurring (there've been some nice demonstrations to this effect). The two notable exceptions that come to mind are Tesla and Lightning Car, but they're targetted at a different kind of consumer. GM, Subaru, Mitsubishi, Aptera, and on and on are all using safe li-ion chemistries in their next gen electric vehicles.

And yes, Toyota *will* put them in the Prius. There have been some delays due to QC, however.

I'm skeptical

[jandrese]

Those are some rather extravagant claims for a technology that appears to be about half thought out (what if we put an engine of some kind on an air car!). My gut reaction is that they pulled that MPG number and top speed straight out of their ass.

Re:I'm skeptical

[PrescriptionWarning]

"My gut reaction is that they pulled that MPG number and top speed straight out of their ass."

almost without a doubt they may have exaggerated quite a bit, but the concept seems kinda solid, maybe similar to how a Turbo or SuperCharger works, only rather than increasing the acceleration, the energy goes toward fuel economy.

Re:I'm skeptical

[thegnu]

Say we halve what they claim for most practical uses (city driving), you still have 400-500 miles per 8 gallons, or 50mpg. Pretty goddamn good for a 6-passenger vehicle.

Re:I'm skeptical

[Raistlin77]

"I want to stress that these are estimates, and that we'll know soon more precisely from our engineers," ZPM spokesman Kevin Haydon told PM, "but a vehicle with one tank of air and, say, 8 gal. of either conventional petrol, ethanol or biofuel could hit between 800 and 1000 miles."

Re:I'm skeptical

[palegray.net]

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Re:I'm skeptical

[nospam007]

Air could be compressed with the energy used in braking. The scary thing about compressed air is what could happen in an accident. Lugging around an explosion-proof thick walled vehicle might negate the fuel savings. ....

Any diver has such an 'explosion-proof' compressed air container on their bare backs.
You just use a few dimes of electricity to fill the tank(s).

It's the tech of Luxembourg-based MDI company of Guy Nègre
http://www.theaircar.com/

Re:I'm skeptical

[CrimsonAvenger]

What your describing is called "Nitrous Oxide". It is compressed air with nitrogen added for its cooling effects on a motor. Adding compressed air to an engine increases the amount of air in the cylinder, and allows you to increase the amount of fuel in a cylinder without making the mixture too "rich" (rich means too much gas, lean means too much air).

Adding compressed gases would allow high performance to be gained out of a small motor, but would not increase the overall fuel economy of said motor.

you can read about Nitrous Oxide Here [wikipedia.org].

Oddly enough, nitrous oxide, as described in the wiki article you mentioned is nothing like the description you provided. Perhaps you should reread the article.

Re:I'm skeptical

[zeet]

Turbochargers do increase efficiency. The only reason that turbocharged cars often do worse than non-turbocharged cars is the tuning. Small turbodiesels often get better fuel economy than similar output non-turbo diesels.

Re:I'm skeptical

[blhack]

Let's see. From your original post...

It is compressed air with nitrogen added for its cooling effects on a motor.

Air is a mixture of nitrogen, oxygen, and other trace gases. Nitrous oxide is a chemical compound. There's a difference. This is like 8th grade chemistry here. If you still can't tell the difference, reflect that breathing air causes you to stay alive and breathing nitrous oxide causes "analgesia, depersonalization, derealization, dizziness, euphoria, sound distortion and slight hallucinations". You're taking what I said out of context. Read the post that I replied to. They're talking about using compressed air "like a turbo". Obviously whoever posted it has a very limited knowledge of automotive performance. I called N2O "air" so that they would understand the correlation.

As far as N2O vs O2s effects on a motor: go talk to a mechanic, specifically one that deals with high performance engines. Ask them why you need to use N2O instead of straight O2. Every single one is going to tell you that O2 burns too hott. The nitrogen helps cool the motor down.

Why is this such an issue? You obviously have no clue what you're talking about. My OP was not inflammatory at all, just calm down.
Its Friday for crying out loud!

I just want to know

[RandoX]

How much does a gallon of air cost?

Re:I just want to know

[hal2814]

It depends on where you're at.

I was over at Spaceball City the other day and a gallon of Schweppe's Air was $4! Spaceballs: The Air was even more expensive at $5. They had some cheap off brand air for $2.50 but you never know what you get with the generic stuff.

On Mars, there's just an outright tax on air that everyone pays. It's like 15% of your income but there are expemtions for midgets and girls with 3 hooters.

Re:I just want to know

[mdsolar]

Electric vehicles can be about 75% efficient including regenerative breaking. Presumably the drive train will be used for some slowing here recharging the air tank. Compressing air always produces substaintal waste heat so the base efficiency will be less than for a battery-motor combination. Let's say that they do well and get 50% efficiency on compressing/decompressing. In that case, if we expect about 0.2 kWh/mile for an electric vehicle, we might get 0.3 kWh/mile for this vehicle. That is about 3.3 cents/mile (11 cents/kWh). For a 30 mpg car at $3.00/gal we get a fuel cost of 10 cents/mile. So, the cost could be about a third of the cost of gas.

Interesting concept

[KublaiKhan]

A bit different than the usual 'hybrid' gas/electric design.

I'd like to know how the air tank would be refilled, though. I mean, gas stations already have air compressors for your tires, but would that put out enough pressure to fill the tank in your car?

Or will this strictly be an 'around town' sort of car, and you'd have to rent something for long trips?

Re:Interesting concept

[NewAndFresh]

Not sure about this one, but of one (air only) version:

It will take only a few minutes for the CityCAT to refuel at gas stations equipped with custom air compressor units; MDI says it should cost around $2 to fill the car's carbon-fiber tanks with 340 liters of air at 4350 psi. Drivers also will be able to plug into the electrical grid and use the car's built-in compressor to refill the tanks in about 4 hours.

I wonder how much those custom air compressors cost?

Re:Interesting concept

[KublaiKhan]

Not necessarily--and given that most air compressors run off of electricity, this allows the use of renewable sources without much difficulty.

It's essentially, if you think about it, an electric car without having the electricity onboard.

Re:Interesting concept

[yog]

The air car may herald a whole new era in energy currency. Far from being a specialized and refined product extracted from the ground at great cost, air is freely available, and the stored potential energy of the vehicle is created by a pump. We will start to look at stored energy as the currency rather than a high energy liquid like gasoline.

Imagine a barter system in the future where we might have to get on an exercycle type of machine to pump up an engine. The local diner might charge either $10 for a meal or one hour on the pump. Homeless and working poor could thus eat for the cost of an hour's exercise.

If you run out of gas in the middle of nowhere, just get out the pump from the accessory compartment in the trunk, hook it up, and start pedalling. After 3-4 hours of fat burning cardiovascular workout, you will have enough stored energy to move your car 20 miles down the road to the service station. And as an added bonus, you'll be in fantastic shape!

Buildings could hook up pumps to revolving doors as a way to "steal" energy to power their lighting systems, etc. Even the floors might consist of pistons hidden under the carpet that are compressed as you walk on them. Walking down a hall would feel like climbing a stair, something the health newsletters advise us to do more often anyway.

Of course, people in windy areas would probably want to use windmills to directly pump up our cars overnight.

It's interesting stuff to think about.

Re:Interesting concept

[Rude Turnip]

I propose we call this new currency "energon cubes."

Re:Interesting concept

[Anonymous Coward]

These cars will have their air tanks filled to super high pressures. You will never get a usable compact human powered refill pump, let alone fill the car at a rate of 5 miles per hour of effort.

However, if the trunk contained a folding bicycle, you could ride 20 miles in a bit over an hour, and fetch help.

Or you could just call for road service on your cell phone. I can imagine tow trucks being equipped with high-speed air pumps to refill air tanks of stranded vehicles. Those high-speed pumps would be powered by gasoline or diesel, of course!

Re:Interesting concept

[Bagheera]

Interesting concept, but human beings just don't produce all that much horsepower. I mean think about it. Could you push your car 20 miles in 3 to 4 hours? Must people would be challenged to walk 20 miles in 4 hours, let alone do it pushing a car. Now, factor in how much energy you lose to heat compressing the air for the tank, and you see where this is going.

Compressed air really isn't an ideal energy storage media. Though it does have the advantage of being freely available and non-toxic.

As for working off a meal, I remember more than one lunch during High School that I paid for doing dishes in the kitchen. Barter systems exist in small scale all over the place. Usually involving goods or services that are more specialized than raw labor.

Neat concept though. . .

Cheers,
Bagheera

Re:Interesting concept

[Chandon Seldon]

I think you're massively overestimating the amount of energy that humans can generate.

Here's some math:

The recommended daily energy intake for a person is around 2000 food calories. That's around 8 million joules. A Watt is a joule per second, so a humans entire daily food intake is (with perfect efficiency) is almost enough to constantly power a 100 Watt lightbulb.

The smallest engine that has been used in the Smart Fortwo is rated at 37,000 Watts. That means that the output of the engine on a tiny car is equal to the *entire energy usage* of 370 people.

In conclusion, when we accept the fact that humans probably can't use their entire energy supply to power your electricity generating bicycle, your idea is off by at least 3 orders of magnitude. Sorry.

Easy

[TheMadcapZ]

We steal it from Druidia. Better get working on Mega-Maid.

Re:Easy

[electrictroy]

I've already got a car that gets close to that:
- Honda Insight - 80-90 mpg in real world I-95 driving (mine)

Volkswagen is also building a car that will get 240mpg, although it's only a two-seater. It will arrive late 2009 (europe), and hopefully hit the U.S. sometime shortly after.

Re:Easy

[Sporkinum]

In India, a Honda Insight is a 6 passenger vehicle.

Re:Easy

[Foobar of Borg]

Better get working on Mega-Maid

Well, I heard that the "recharge" and "drive" settings for the air car will be labelled "suck" and "blow", respectively.

Re:Easy

[Gordonjcp]

I had a car which got 85mpg a few years ago - the Citroën AX 1.5D - which, unlike the Honda Insight, could actually take four adults and some shopping (although the two adults in the back had to be fairly small). It probably wasn't quite as safe in a crash as an Insight, but had the advantage that pedestrians and cyclists would hear you coming.

Re:Easy

[magarity]

In India, a Honda Insight is a 6 passenger vehicle
 
In South Africa it could be a cattle truck.

Re:Easy

[Anonymous Coward]

"- Honda Insight - 80-90 mpg in real world I-95 driving (mine)"

Bullshit.

No, no, no, shut the fuck up, you're lying.

God the things losers like you will lie about to get attention...

Re:Easy

[The One and Only]

This is loosely-informed speculation, but I do know that American safety tests are usually crash tests to ensure that the passenger compartment can survive a collision. I don't know much about European tests, except that they do have a "moose test" that involves testing the maximum speed that a vehicle can swerve. So maybe, just as the American tests favor heavily-armored body types, the European tests favor performance and agility. Since Europe has stricter licensing than America, they can more easily presume that drivers are capable of executing these swerves. In America we allow any idiot to drive, so we test for crash survivability. The difference in design between US and European cars probably stems from this.

Re:Easy

[s.carr1024]

I've already got a car that gets close to that: - Honda Insight - 80-90 mpg in real world I-95 driving (mine)

Sure ya do buddy, sure ya do.

The highest EPA mpg estimate for highway was 68 mpg using its completely bogus pre-2008 methodology. I'd love to know how your car has a more than 30% mpg improvement than a real Honda Insight.

Re:Easy

[Anonymous Coward]

MY Insight runs on air and dewdrops and gets 153.6 mpg. And I'm married to Morgan Fairchild! Commander Taco was at our wedding. And I run Windows and it has never crashed. Not once. Not ever.

Re:Easy

[Rei]

This may seem like a troll, but it's 100% correct. Those numbers are impossible, even with drafting.

As for fuel efficient cars, the most efficient vehicle coming out in the near future is the Aptera Typ-1e/Typ-1h, but the Typ-1h only gets 130mpg when its battery is depleted. And this is a car with a 0.11 drag coefficient (compare to 0.26 for a Prius). It doesn't get much lower than that and still be streetlegal.

Re:Easy

[Gordonjcp]

UK. You don't get them in the US. This is the equivalent of 70 US mpg, not bad for a proper car with a proper boot and a low environmental footprint (none of those nasty toxic hybrid batteries).

Re:Easy

[Gospodin]

Since Europe has stricter licensing than America, they can more easily presume that drivers are capable of executing these swerves.

I'd be careful about making generalizations like this. France, for example, has a "special license" category which allows you to drive below a certain speed (I think it's 50 kph) and only on the shoulder. It's useful in rural areas where elderly need to be able to drive but can't pass the more stringent normal licensing test (which, you're correct to observe, is tougher than the U.S. standard).

Re:Easy

[Elbows]

I think you're correct. It mentions the seatbelt thing on the results page for the PT cruiser tests. There's some additional padding to protect the legs of a passenger not wearing a seatbelt, but if you are wearing a seatbelt the pads just provide one more surface for you to smash into before the belt stops you.

Re:Easy

[gzerphey]

He may be correct, but he is still a Troll just by the virtue of how he said it.

Some people seem to forget tact online.

Re:Easy

[MightyYar]

A couple of things...

1. VW doesn't sell their TDI cars here primarily because of emissions - European standards are more lax. They are planning on introducing their new "clean diesels" this year, IIRC. The clean diesels are made possible by new US diesel refining requirements (low-sulfur).
2. Diesel takes about 25% more crude than gasoline to produce, so those mileage figures aren't really very useful. Diesel still wins in efficiency, but starts to lose this advantage at wide-open-throttle (compounded by the heavier weight of the diesel engine). In other words, that diesel 40-45 MPG is more like 32-34 in gasoline terms... a mild improvement, not a slam-dunk.
3. Europe has higher taxes on gasoline than on diesel, which explains the cost effectiveness there.

I agree with you - high mileage cars are nice to have available. I had a 1998 Saturn SC1 that got almost 40MPG highway, but at the expense of performance (99 horsepower, yeah!).

Re:Easy

[SerpentMage]

Or if you have had your drivers license revoked because of drinking and driving...

Hey I am not kidding here. They have ads all over here in Zurich Switzerland that go along the lines,

License revoked? No problem rent speed reduced car here...

Re:Easy

[ksheff]

Most of the cars available today are heavier than the ones available in the late 80s/early 90s. Side impact beams, airbags, etc.

Re:Easy

[FlightlessParrot]

AFAIK the "moose test" is a test of swervability that a ?Swedish motoring magazine did, and only started being called "moose test" after an A-series Mercedes rolled doing it. The crash tests are crash tests. For lots of good reasons, European cars tend to be smaller than US ones. That's pretty certainly one cause of differences in survivability design and testing. If the cars from one continent do badly in the other continent's tests, certainly it shouldn't be called protectionism. Another good reason for driving Japanese.

simple

[Anonymous Coward]

For an additional $5000 the car comes equipped with a politician and a special adapter to route all the hot air into the tank.

Rental

[bigattichouse]

I think the only way they'd get past the "burp-car" or "fart-car" stigma would be to start offering them as rental cars - let people drive them around a lot. Then they might have a market. (Unless they just come in at $2500 - then they'll sell a billion of them)

Answer: Mega Maid

[45mm]

Ape 1: SPACEBALLS?!

Ape 2: Oh shit ... there goes the planet ...

"Zero Pollution"?

[johndiii]

Probably no such thing. At the very least, there is waste heat from the mechanical processes of the automobile. The energy require to accelerate a vehicle to a certain speed will be roughly the same, regardless of the source. In the case of the "air-powered car", the energy used to compress the air could come from a coal-fired power plant. Is that better than burning gasoline? I don't know, and I would be very interested to see a comprehensive analysis.

In considering the environmental impact of a particular vehicle, there are a number of factors to consider:

• How the energy is obtained in the first place. From petroleum drilled out of the ground, a coal mine, natural gas, solar power, nuclear power, and so on.
• The efficiency of conveying the energy from the source to the user. Coal and petroleum products are relatively good for this (some loss to evaporation for gasoline, I imagine). For remotely-generated electricity, there would be transmission losses. If you charge your electric car from a solar panel on your roof, much less so.
• How the energy is stored (or storage losses). This is one of the big issues with hydrogen. It tends to seep through containers. Compressed air would be a similar problem. A leak in your compressed air tank has an environmental effect just as a lead in your gas tank, and is harder to detect. It's more efficent to store a liquid than a compressed gas.
• The efficiency of converting the stored energy into motion of the vehicle. What are the thermal losses for state changes? Friction in the engine?

There are probably more factors, some very difficult to isolate. And there are safety factors - gasoline is flammable, but easy to detect if it starts to leak. Hydrogen, on the other hand, you would not notice at all until your car decided to emulate the Hindenberg. :-)

Zero pollution is a good goal, but unless all of the factors are considered, it's just marketing hype.

Re:"Zero Pollution"?

[Dusty00]

Large scale power generation such as power plants are significantly more efficient than the small scale of an internal combustion engine. That's the difference. If my car is powered by electricity generated at a power plant, yea there's still pollution but a lot less energy is wasted and hence, less pollution per mile.

Re:"Zero Pollution"?

[mh1997]

1. Unlike an electric car, you do not have an expensive, heavy battery that you have to figure out how to recycle when it is dead. 2. The internals of the car are likely much simpler than with an electric car. 3. No exploding batterys / hydrogen. This is just compressed air. If there is a hole in the tank, it leak air. The tank is designed to fail gracefully. 4. It's likely much easier to outfit a gas station to dispence air than hydrogen. 5. You can fill it at home if you want.

Assuming the technology works for an air powered car:

1. You just have an expensive heavy onboard compressor that you have to figure out how to recycle when it is dead

2. Probably a wash, a compressor, tank, and airlines are probably as complicated as a battery, motor, and wires.

3. Not everything fails as designed, sitting on a tank of compressed air when it explodes would blow.

4. True

5. Which makes the profitability and motivation of outfitting a gas station diminish. Anybody could store compressed air and either give it away or undercut the market.

I hope it works, I am tired of paying more for my groceries because "Big Farming" has lobbyists that convinced politicians to subsidize the price of corn produced ethanal.

Re:"Zero Pollution"?

[cupofjoe]

Another Hindenburg reference. Great fricking Caesar's Ghost.

Seriously, though - and on a tangent for a sec - he's got a point. No, not about a hydrogen-fueled car ACTUALLY bursting into flames a'la the great Lakehurst weenie roast (that's why he used a smiley-face, I guess) but - unwittingly - about the public's perception of the implications of having hydrogen on-board a road vehicle.

The truth is, technology wants to go in a safer direction. The US DOE is spending a lot of money - well-spent, in my opinion - on developing components of an automotive approach to hydrogen fuels, including infrastructure, end-to-end efficiency and cost, and of course materials science and engineering.

Check out http://hydrogen.energy.gov/

The long and the short of it is this: the current standard is to store compressed hydrogen on-board in 5000 psig tanks; the tech maturation for this approach is to up the ante to 10000 psig. Yikes; no wonder the public has the wrong idea - that's a lot of mechanical energy stored up in there. Some of the more interesting (but not new) technology DOE is funding is for "absorptive" storage, both liquid- and solid-state, wherein the hydrogen isn't at high levels of compression - rather, it's safely (for the most part) tucked away inside the molecular structure of a parent "carrier" substance. At fairly low pressures (~15-150 psig), for the most part.

Okay, tangent over. In the interest of full disclosure, I am a hydrogen materials engineer. And I'm WAY more frightened of gasoline vapors than I am of hydrogen in any form.

Cheers,
--joe.

Re:"Zero Pollution"?

[horza]

In France over 80% of energy is nuclear and electricity is cheap. I know the UK has high renewable energy targets. It is easier to monitor pollution from a small number of coal/oil plants than emissions from millions of vehicles. I don't think it's ever been reducing pollution and cost of transport that has been the problem with electric/air/hydrogen but the initial purchase cost and the limited range. Especially the latter.

The reason the Tesla can out-accelerate a Ferrari is that there is no loss through a variable transmission, all the torque from an electric motor goes directly to the wheels. I'm not sure about the compressed air car. Both compressed air and electric use no fuel whilst stationary, unlike gasoline cars (except hybrids).

Transmission losses: there is a cost associated with distributing tons of gasoline around.

The efficiency of converting the stored energy into motion of the vehicle: for any kind of combustion engine the maximum efficiency is 40%. For hydrogen fuel cell 100%. As for friction: electric/air = less moving parts = more efficiency.

I'm not going to bother debunking the Hindenburg 'exploding hydrogen' myth, that's been done to death on Slashdot.

You have to be short sighted to think it's not going to happen, it's a question of how and how long. As the saying goes, once you know something is possible then all the rest is simply engineering.

Phillip.

Re:"Zero Pollution"?

[Darkfred]

Call me uneducated, but cars running on air sound much less like marketing hype to me than electric cars. Ok, uneducated.
You seriously believe that the proven technology in electric vehicles is more hype than this? This article is entirely hype, these guys have nothing to show except for estimates. They are looking for funding.

1. Unlike an electric car, you do not have an expensive, heavy battery that you have to figure out how to recycle when it is dead. You could cut the FUD crap with a knife.

The batteries for the Tesla roadster, an actual production vehicle, unlike this concept. Cost around $9000. And need replacing every 5 years. (This adds a fixed cost of around $0.12 a mile for my average driving, but I don't commute very far) Battery prices will probably drop to 1/4 this by the time they need replaced.

LI batteries must be drained to be disposed of or recycled. But the disposal process is relatively non-toxic. This should not be a major concern. Any retailer who sells batteries will dispose of used ones.

On the other hand, The air car requires a multi-stage compressor that can hit over 4000psi. These are usually gas powered, and incredibly loud. Most compressors are slow, low volume scuba systems. And the only commercial way to purchase air in the high volumes needed is high pressure nitrogen canisters specialty manufacturers. They are incredibly expensive, and dangerous.
In addition to this, they have a speed limit set by thermodynamics. They can only fill as fast as you can dissipate the excess heat. In reality you are going to need to keep this disconnected from your house and use a giant tank so you can continously fill it.
And your neighbors are going to just love the noise. Jet engine loud.

2. The internals of the car are likely much simpler than with an electric car. You have obviously never worked with pneumatic systems. They are complex and incredibly finicky. Throw in the element of danger, and the need to cycle the system repeatedly to find problems and you will not be able to get a regular mechanic to touch these.

3. No exploding batterys / hydrogen. This is just compressed air. If there is a hole in the tank, it leak air. The tank is designed to fail gracefully. LI batteries no longer explode. High energy car size power packs which have been crash rated are already in production for both the Tesla and Volt cars. (in addition to the numerous electric scooters and motorcycle kits)

A 4000psi carbon fiber air tank does NOT fail gracefully.
If a fault ruptures the tank it will tear like paper! The explosion will only begin to regulate when the air around the car flash freezes. The freezing, high pressure air will cause burns across the passengers bodies. And they will never hear again. (lets counter fud with fud :) )

4. It's likely much easier to outfit a gas station to dispence air than hydrogen. No one is comparing this to hydrogen seriously. Hydrogen has been dead ever since batteries reached a higher energy density.

5. You can fill it at home if you want. See above,
What they fail to mention is that the home compressor they sell will probably only fill the car fractionally compared to the industrial size one for filling stations. The energy goes up as the pressure increases. Realisticly they could probably hit 1500psi quickly on a large volume with standard consumer equipment. Which gives you less than 1/3rd of a full charge.

Well, if it meets their claims...

[brennanw]

... then I think I'd be willing to buy one. Although I really don't like the way they look. Still, I could suffer through the faux-Jetson design if it's a genuine 100mpg driving experience.

I do dread the inevitable tech support calls, though.

I'd buy one

[BigJClark]

and a litre of your best snake oil, sir!

Great, environmentally friendly cars!

[apathy maybe]

Small cars that use little fuel are great. And in cities (where most people drive), it doesn't matter if it only gets a few hundred kilometres (did someone say miles? what are they?), as that is more then enough to get you home again.

As for speed, again, if you are driving in a city, there is no need to drive more then ~60 kilometres an hour (~30 miles an hour I think).

(Of course, I still prefer my (push) bike, bikes are a heck of a lot safer then cars, imagine if everyone had a bike instead of a petrol guzzling car. There would be a lot fewer accidents. Of course, sometimes you need to carry more stuff or more people, simple, just ring up your local car sharing co-op!)

Re:Great, environmentally friendly cars!

[RightSaidFred99]

I don't know what city you're in, but here we have freeways (65-75 mph) and even on the main streets the speed limit is 45mph (so most sane people go 50-55mph).

Re:Great, environmentally friendly cars!

[bishiraver]

Which is why typical electric cars don't get traction in the US.

A majority of people live in suburban areas - not cities. The way these areas of the country are laid out, one must drive 5-10 minutes to your grocery store, 10-20 minutes to work (usually on a highway requiring speeds of 60+mph / 96kph), 5-10 minutes to the local big-box store (walmart, target, kohls, best buy, etc). This is one of the reasons I hate suburbia - it truly condones and perpetuates impracticality. Imagine riding your bicycle 12 miles to work along a four-lane-wide highway with cars whizzing past at 70mph! The solution to this, of course, is to get people to move out of suburbia and into "new urban" style developments - but people see their houses as an investment instead of a liability (which many houses are proving to be) and are loathe to give them up. Even if they are poorly built McMansions. To learn more about this phenomena, see: TED Talks James Howard Kunstler: The tragedy of suburbia.

That is why this car is so important. It has a decent speed, a long range, and can fill up at regular gas stations.

vaporware

[metamechanical]

This gives a new meaning to the word "vaporware" :P

Re:vaporware

[croddy]

Vaporware? Shit, dogg. We got the vapormobile.

Pirate Car?

[jetpack]

FTFS: "The vehicle be introduced to the market"

Arrrrrr, Matey!

Looking Forward to It

[Phoenix666]

We need a paradigm shift in transportation, because it causes so much climate change.

My immediate family is lucky, economically--we live in New York and don't need a car; but that doesn't exempt us from the environmental consequences of the internal combustion engine.

But even environmental consequences aside, the rising cost of oil has put the squeeze on the rest of my family who aren't fortunate enough to live in areas where public transportation is available/reliable/efficient. When you consider the relative share of annual income that they pay for basic transportation versus mine, it's dramatic how high such a fundamental cost of living is in the United States.

So, ask yourself--how competitive can an economy remain when it spends such an out-sized amount on such a basic service? It should be driving the costs of transportation down to the level of a utility and investing the surplus in cutting-edge technologies.

Energy state conversion

[Dzimas]

OK, so you use an electric engine to drive a compressor which then drives the wheels. Or - even worse - you'll use a gasoline engine to compress the air. It's true that you'll get "zero pollution" while driving, but this vehicle is going to use significantly more energy than a vehicle that uses an electric or gasoline engine to drive the wheels directly. And that means *more* pollution, not less. There is a reason that we don't use compressed air to anything larger than toy cars and rockets - it has an incredibly low energy density compared to a tankful of hydrocarbon-based fuel.

This is yet another "clean energy" idea that preys on the naieve.

Re:simple - rip off

[MadCow42]

>>For an additional $5000 the car comes equipped with a politician and a special adapter to route all the hot air into the tank.

That's a rip off - around here, you can buy a politician for a lot less than $5000. :)

MadCow.

Pressure

[mikej]

How heavily compressed is the air in the storage tank, and how rugged will the tank be? Think about the consequences for both cars if this thing gets rear-ended or sideswiped hard enough to rupture the tank...

Re:Pressure

[jdunn14]

By god, this is america, if we can make a river catch fire we sure as hell can make the air burn....

But What About...

[MarkAyen]

TFA is long on hype, but severely lacking in details. And contradictory, or at least misleading. It refers to the Air Car as "gas free", but later states that is uses a "supplemental energy source" for speeds over 35 mph and that it can take "conventional petrol, ethanol or biofuel". Maybe that's not strictly speaking "gas", but until we have a biofuel refueling infrastructure, that means good old pump gas.

There are also a lot of unanswered questions about the pressurized air tanks. How much pressure will the tanks be under? What happens if a tank ruptures? How are the tanks filled? (If you have to fill them between trips, then there will be an energy cost associated with that, probably not an insubstantial one.) How easy are they to service/replace? How much energy is required to manufacture/remediate them?

As with so many other "green" solutions, we may ultimately find that the real energy savings aren't all they're cracked up to be. Don't get me wrong -- I applaud anyone working to reduce our dependence on fossil fuels. I just believe we ought to think more critically about what we're buying into.

Re:engery to compress?

[plague3106]

Well, we could go nuclear. At any rate, having millions of "clean" cars and a few plants to generate power will let us focus on making the plants as clean as possible. Then if fusion ever happens, we can start building those without changing the cars.

Indirection solves yet another problem!

Cold Weather Friendly?

[jekewa]

I saw this on the television and thought it looked pretty cool, pun kind of intended.

Arguably one could compress one's own air in the garage with a wind or solar powered compressor and fuel the thing for "free." Certainly that would be an option for some (in windier areas) people and even filling stations. Otherwise, of course, we're just moving the pollution from the streets to the power plants that then have to power all of the compressors.

The thing that kicked the idea for me is that the car seems potentially impractical for those of us that live in temperate regions. For a large part of the year, our vehicles need to generate heat for the passenger compartment. In your typical gas-powered motorized vehicle, this is heat taken from the cooling system. Sure, the old VW Beetle had an electric heater in it, but anybody who had one in sub-zero climates can tell you that they don't always cut it. It's probably the case that the improvements in seat-based heating and technology in general will make the heaters more useful. Perhaps the size of the cabin will help. It also needs to be considered that the light-weight construction of the body may not allow for an awful lot of insulation.

Along the same lines, those tiny wheels wouldn't make it through the snow. A 75HP motor seems like enough to power some larger wheels, but what's the torque like, and how much impact is that larger drive-train gonna have? And once you start adding that bottom weight, how much is that going to force changes in the rest of the car, and will it spiral out of control such that the power plant is no longer sufficient?

In warmer areas, like I'd like to move to, it seems a very practical commuter vehicle. I have to imagine someone has thought of routing the exhaust through a cooling system, allowing the engine to cool the cabin without needing an environmentally unfriendly air conditioner. On good paved roads the tiny wheels might only be a hindrance to top speeds, where larger wheels might be needed for rougher roads, like those with cracks and potholes. (Yeah, I may have a thing against tiny wheels...)

There is also a safety factor. In places where everyone drives small cars, this will fit right in, but in the US, too many SUVs and large sedans compete for the same road as these. It'll probably be the same as with motorcycles; they're safer when you get a bunch of them together than individually ripping through traffic. Once there's a lot of them on the road, this should shift so that the small cars will dominate, and the larger ones will be the exceptions.

Heck, someone should suggest to "reverse" the HOV lanes and force the big vehicles over there, allowing the smaller vehicles to have the other lanes; which could probably be narrowed, and would be less congested as all of the vehicles would be shorter and everyone would be closer to their destination by the time the traffic jam started .

Is it really cheaper?

[Iberian]

Say instead we took the same car and replaced the engine with a small 1.2 litre diesel. Now calculating in the cost of the compressed air and comparing it to the cost of diesel to go 1000 miles which is cheaper?

May even debate which is greener considering that the compressed air didn't jump in the tank itself

Re:Ugh

[Midnight Thunder]

Why do they have to make the friendly cars so damn ugly?

Maybe because they aren't really giving high priority to the market or feel that the "environmental hippies care more about function than looks". Truth is, the there is a growing market of "environmental hippies" that have both money and sense of style. Maybe its time they took some of their industrial designers off their 10 tonne Enviro Pollution Vehicles and actually applying them to making environmentally friends vehicles which look good.

In short: yup, I agree with you :)

Has anyone ever seen this thing? Vaporware?

[Animats]

Is there a drivable prototype of this thing? Has anyone from Motor Trend or Auto Week ever had a good look at it? For any real car, the prototypes precede volume production by several years.

Accusations of fraud are flying between the Air Car people.. Apparently there are two Air Car groups, and they don't get along.

Tata Motors has nothing on their web site about the "air car". They do have a page of their concept cars, and the Air Car isn't on there. They're coming out with the Tata Nano, at $2500. The Tata Nano is conventionally powered. There's an electric version of the Tata Ace mini-truck, and those should be coming to the US this year. But there is no Air Car or "City Cat" from Tata that I can find.

This looks like vaporware.

Danger, Will Robinson

[RealProgrammer]

I think Spielberg built a huge PR hill to climb for the litigious American market. Ever see Jaws? As Mythbusters showed, in the extremely unlikely event that an air tank ruptured, it would typically expirate rather explode. It would be difficult indeed to make the tank explode, but that's the image I have.

A twist on that by which the energy industry could rake in profit is by declaring it unsafe to use compressed air. Instead only compressed CO2 or Nitrogen should be used, to avoid fire hazard.

O'course, that kind of undermines efficiency for braking, which should best be done by compressing air. Maybe they could use two tanks and use the difference in potential (pressure) between the two in a closed system.

Re:Danger, Will Robinson

[elguap0]

That's no worse than what's depicted in Hollywood for gasoline powered autos. How many times have people seen cars blow up spontaneously with one bullet to the fuel tank? This was also debunked (and then rebunked) on mythbusters.

i met an indian woman

[circletimessquare]

and told her that i liked her tatas

she slapped me

why does she hate fuel economy?

Re:I'm skeptical -- me too.

[JonTurner]

I wish them luck for success but I too am feeling skeptical. Here's why:

>>400-500 miles per 8 gallons, or 50mpg. Pretty goddamn good for a 6-passenger vehicle.
Yeah, but notice they say "six passenger vehicle" and not "vehicle with six passengers." BIG difference.

With very low-hp automobiles, the extra weight of even one passenger can have a tremendous impact upon performance and economy. (I drive a 40hp 1964 VW Beetle so I know from whence I speak). Driven alone, my car actually performs as well as most modern cars. Add a couple passengers and suddenly it's sluggish and MPG falls into the mid-20 range.

>>Say we halve what they claim for most practical uses (city driving), you still have 400-500 miles per 8 gallons, or 50mpg.

Judging from the tone of the press release (they don't seem to believe it) the 95mpg figure doesn't seem likely at all. And if we take half that figure, 50mpg as you suggest, it's still better than most gasoline vehicles, but roughly on par with turbodiesels. But we need to consider this a bit further. Because low-hp vehicles are greatly impacted by laden weight, if we were to take this 6-passenger vehicle and add a couple passengers I think we'd see that 50mpg figure fall further, possibly into the range of traditional gasoline vehicles which puts it well BELOW that of turbodiesels! It takes approx 35 hp to maintain 60mph in a vehicle with average aerodynamic drag. This vehicle has approx 75hp equivalent. That leaves 40hp to accelerate a vehicle with up to 900 lbs (6x150) of passengers plus the weight of the car. Subtract parasitic losses such as alternator (headlights, heating??) or a/c compressor drag (-5 hp) and it's anemic at best. Meaning it will struggle on hills, and passing on the interstate will be difficult.

Disappointing, but it helps us realize just how efficient a fuel-injected, turbo intercooled internal combustion engine is.

The pollution is far less

[WindBourne]

Everybody likes to point out that EV comes at a cost, and always ignore that EV will slowly pick up the energy from AE or nukes, which have very limited emmisions. A decent page is here.

Re:engery to compress?

[sm62704]

Well, we could go nuclear

Nuclear waste needs to be stored forever. I don't know if that's worse than emmissions and global warming or not; I'm just a layman.

By the time fusion happens, all our present tech will be obsolete anyway.

Exactly

[JonTurner]

If they're heating the air charge to increase the volume/pressure then I suppose that efficiency would increase as ambient air temperatures decreases, but what does this automobile do to provide passenger cabin heat? If the heat extraction from the burned fuel is efficient (and I imagine it must be) then waste heat is unavailable for the cabin.

This is one of the substantial (and as yet to date, unsolved) issues for an all-electric car serving in anywhere other than a tropical climate -- at some point you must provide heat to the cabin. Electrical resistance heat is incredibly inefficient, heat pumps are efficient above about 30 degrees F (though they are nearly worthless below that temperature), and further heat pumps have a very low thermal output (e.g. it would take FOREVER to warm a car on a 30 degree F day).

This car might succeed in Southern California or Florida... maybe texas, but seems impractical for anything other than summer use in the majority of American states. (Even the southwest -- you can die of hypothermia in the desert at night.)

It's a shame, because I'd love to have some more options for transportation other than gasoline engines.

(BTW, I never knew about electrically heated VW Beetle seats and I've been restoring them for years. I suspect that's some aftermarket "solution." The Beetles (and all aircooled VWs & Porsches) capture heat from the outside of the exhaust manifolds.)

You'll only need a footpump to refuel

[MrSteveSD]

It will definitely keep you fit. I believe the vehicle will also have a hole in the floor so you can supplement the engine with some legwork.

Snake oil

[killbill!]

In this house, we obey the laws of thermodynamics!

Compressed air is a terrible way to store energy. There's about 250 times less energy in compressed air than in gasoline. Do the math. It's impossible to make a useable car that is powered solely by compressed air. The energy just isn't there.

It's possible, however, to make a working hybrid gasoline-compressed air vehicle. But as far as the hybrid component goes, batteries are a much better candidate.

The car in TFA is based on the MDI AirCar, which is a greener version of the Moller Skycar. In other words, a scam. Whenever the company needs money, they write a few press releases, and some naive investor falls for it.

The company has allegedly dozens of licensing deals all over the planet. But not a single production vehicle has been built. It was supposed to be coming out "real soon now" 10 years ago. In 10 more years, it will still be "right around the corner".

Efficiency loss in cold climates

[JungleBoy]

I live and work in Montana & Alaska, and wonder would there be any efficiency loss at low temperatures? How would these air engines work at -40[c|f]? Also, since they are decompressing air, creating a chilling effect, would this cause additional problems at low ambient temperatures?

it's stupid...

[atheist666]

1. You spend energy to compress air. Air heats up, heats up tank, tank cools back down to ambient temperature. Significant energy lost to waste heat. 2. You make your air-car go. Air decompresses, cools down a lot. Significant losses to efficiency. Problems with icing. 3. Your air car stops after half a mile. Your 6-person vehicle doesn't have enough compressed air tank space with current technology to approach the energy density of standard batteries, let alone hydrocarbon fuels. 4. *PROFIT*!

Noob

[furbearntrout]

You must be new here.

In Soviet Russia, cars overload you!

See, like that.