Wapsi Square Forum

NOTDilbert wrote:About compressed air....

During WWI and WWII, the Jersey docks where amunition was loaded onto ships for Europe used compressed air locomotives to shunt amunition cars from warehouse to dockside, The issue was one of fire safety - oil, wood or coal-fired engines dropped sparks/cinders/smouldering oil from the fireboxes; not something you want sitting undera boxcar of gunpowder.

Closer to (my) home - at the turn of the (last) century, the Fort Smith Wagon and Carriage Works consisted of several buildings about a hundred yards apart. Flats of wagons and carriages under construction were shunted from building to building via compressed air locomotives, for the same reason.

A lot of steel mills and power plants used fireless locomotives that ran on stored steam. More efficient than compressed air because of the problems with heating and chilling mentioned somewhere above.

alj_ws wrote:

Bathorys Daughter wrote:I think the issue should be electric cars or other types of non IC engine cars. I believe the way too go is the compressed air engine car. They can have much the same range as an IC engine car and can be "recharged" in a short time with high pressure pumps. They certainly have the same range as an electric car even now. No problems with battery replacement and disposal issues.

unfortunately, storing energy in compressed air is a rather costly proposition in term of efficiency because of the big heat generated while compressing and the big cold when decompressing. More worrying is the safety issues. low pressure (7-20 bars) tanks must be checked annually in the industry because they are considered unsafe, and a car would need either a very big tank at those pressures, or a small one one but at eg 200 bars. If that explode, it would makes a lot of damages. Not something I would sit on.

early attempts at compressed air cars and rails

Most people experimenting with them are using multiple smaller tanks instead of one large one. You can find some out about them by searching for the topic on Youtube. It's like anything else, procedures will be put in place for safe operation. After all, even in a car today you are sitting on gallons of highly flammable and potentially explosive fuel. Over the years methods were developed to make the system reasonably safe. At least with air, you're not likely to burn to death should it blow. Heck, all sorts of bad things can happen with home use tanks of LP gas. There's a huge bomb waiting to go off, but they rarely do. Low pressure, yes, but very explosive fuel. At least the explosive-due-spark thingy isn't a real problem with compressed air.

Air cars sounded interesting when I first heard of Tata in India, but they aren't practical outside of those previously mentioned special uses. Everything about them comes up short: power, range, energy efficiency. Instead of using electricity to power the compressors to fill the tanks you get more bang for your buck storing that electricity straight into batteries.

Another thing to consider about full electric vs hybrid or standard vehicles... maintenance.

An electric car doesn't have an ICE, which has a bazillion things that go wrong with them. Fuel pumps, oil leaks, gaskets, belts all over the damn place...

Electric? Doesn't. In fact, some designs don't even *HAVE* belts, they use gears to transfer energy. It's not going to leave you stranded on the side of the road because your radiator blew. Or because your water pump failed. No worries about leaks in the oil or gas or coolant lines. No air or oil or fuel filters either. Also, since most electric vehicles have tandem electric motors sharing the load, the actual wear on the engines is significantly less than you'd find in a traditional internal combustion engine. So much less wear and tear on the system, fewer parts designed to require frequent replacement (belts, hoses, filters, gaskets...) means actual maintenance costs are going to be fairly low. In fact, other than brake pads, tires, and suspension... there may well not be *ANY* maintenance costs in your first 100,000 miles. No oil changes, no filters replacing... no transmission to worry about...

The counterbalance, of course, is going to be the battery. It's the big spooky nebulous expense which opponents always beat the drum about 'ZOMG! It's going to be SO expensive to replace the battery that it's 'fuel' cost is going to be even HIGHER'. A completely false statement, but hey, it's an emotionally false statement, which apparently means something to most people. To be honest, all we have are lab tests and estimates, there's no way of knowing how quick your battery is going to go out. However, there's some guidelines we can use.

Most of the electric vehicles I linked in my last post have a guaranteed warranty on their battery for 100,000 miles. Tesla's leads the pack, of course, but in fairness, let's use the average rather than the leader, to avoid looking like we're trying to massage numbers.

The other problem with calculating the cost of battery replacement is the fact that battery technology is advancing by leaps and bounds. In five or ten years, the cost of a LIon battery may well be a fraction of what it is now. Or they may have switched to something even more economical and/or efficient (in which case, it may well cost more, but provide a substantial energy efficiency boost).

Rather than using Tesla's numbers, which wouldn't really be fair since they are so ahead of the pack, let's use the numbers from the Nissan Leaf.

It's got an 8 year or 100,000 mile warranty on the battery itself. However, an interesting thing while trying to find more numbers, like how much the battery costs at the moment, I ran across this. So it is quite possible to run your car on solar, obviating the whole mess about power grid efficiency. Contact information is there for anyone who wants to ask them about how much it might be, if you're strongly considering this option.

Without being able to find a solid price on one of these car batteries, I can't produce reliable cost efficiency numbers, since that's going to be a pretty major figure in long-term ownership. It'll also be the break-point on how long one owns the vehicle. If it's inexpensive enough, it would be quite worth buying a new battery and keep going, since the rest of the car wears very well.

And if it turns out that the battery is going to be the deal-breaker cost to replace, you trade it in before you hit 100,000 miles. A bit disappointing, I tend to prefer to put 250k+ on my cars before retiring them, but well ahead of the curve. Then the dealer puts in a new battery, and finds a huge market in used electric vehicles, since they can sell it at a lower rate but still turn a good profit, and the actual mechanics and wiring would still be sound enough for the next 100,000 miles.

Never needing to pull into the gas station? Major plus. Only needing to change the pads, tires, and maybe a bit of suspension work in your first 100,000 miles (because there's nothing else *TO* change)... double plus! Never needing to worry about fuel injectors, or carburetors, or starters, or all that hassle... priceless.

Fewer moving parts = much easier to maintain. It's a simple equation, but one which weighs heavily in favor of pure electric cars, and the major reason I'm so hard on hybrids... they still have to deal with all that hassle.

Oh boy, someone mentioned Steam. The concept is intriguing, but the explosion factor makes it too dangerous.

jwhouk wrote:Oh boy, someone mentioned Steam. The concept is intriguing, but the explosion factor makes it too dangerous.

It's not dangerous...it's exciting!

ShneekeyTheLost wrote:Another thing to consider about full electric vs hybrid or standard vehicles... maintenance.

An electric car doesn't have an ICE, which has a bazillion things that go wrong with them. Fuel pumps, oil leaks, gaskets, belts all over the damn place... etc.

Those are all wonderful things, and as soon as the price comes down from the stratosphere I'll consider buying one. Well, that and being able to go a few hundred miles without a recharge. Oh, and being able to recharge it in a few minutes. And then there is air conditioning. A must have for me. Power steering, power brakes. Something large and sturdy enough to give me a good chance of survival on the highway. I can't see buying one just for tooling around town. Whatever I get has to be able to be my all around vehicle. Multiple cars is not really a viable option for me.

I seem to recall once reading about a hybrid in which the only purpose of the (small) engine was to recharge the batteries and maybe produce enough extra power to run the car at highway speeds. The engine was very efficient because it always ran at optimum rpm, regardless of the speed or load of the car at any moment. Seems like that would be a better alternative than directly powering the wheels from the engine or the motor. Plus it was far easier to replace since it didn't have to be mechanically linked into the drive system. And it could charge the batteries when stopped at a light or even when parked.

shadowinthelight wrote:Air cars sounded interesting when I first heard of Tata in India, but they aren't practical outside of those previously mentioned special uses. Everything about them comes up short: power, range, energy efficiency. Instead of using electricity to power the compressors to fill the tanks you get more bang for your buck storing that electricity straight into batteries.

The thing is, for most people, the biggest bang for the buck isn't the determining factor, initial price is. Ease of maintenance may be second. Then there is the recharging time. Air cars certainly have short comings, but could still be the better alternative for many due largely to price. Look at the PC vs Mac. PCs won out, but not because they were the better machine.

Bathorys Daughter wrote:Those are all wonderful things, and as soon as the price comes down from the stratosphere I'll consider buying one. Well, that and being able to go a few hundred miles without a recharge.

You've got about the same range on a tank of gas

Oh, and being able to recharge it in a few minutes.

The MiEV recharges in a half hour. Besides, you generally recharge it when you're asleep.

And then there is air conditioning. A must have for me. Power steering, power brakes. Something large and sturdy enough to give me a good chance of survival on the highway.

Nissan Leaf has all this. So does the Model S and Model Z from Tesla.

I can't see buying one just for tooling around town. Whatever I get has to be able to be my all around vehicle. Multiple cars is not really a viable option for me.

Me either. Which is why I'm excited about the Model Z. 300 miles on a charge, which is about as far as you'd get on a tank of gas. Charge it up when you get home. About the only thing you might have a problem with is if you want to take extended trips.

I seem to recall once reading about a hybrid in which the only purpose of the (small) engine was to recharge the batteries and maybe produce enough extra power to run the car at highway speeds. The engine was very efficient because it always ran at optimum rpm, regardless of the speed or load of the car at any moment. Seems like that would be a better alternative than directly powering the wheels from the engine or the motor. Plus it was far easier to replace since it didn't have to be mechanically linked into the drive system. And it could charge the batteries when stopped at a light or even when parked.

You're probably hearing rumors about the Volt, unfortunately it's not quite as good as it seems, and still has all the many and varied problems that internal combustion engines have. Also, electric engines always run at optimum RPM, or rather, 100% torque since RPM is a meaningless number to electric motors, from the get-go. Regenerative breaking does charge the batteries when stopping, and comes standard in every electric vehicle I've heard of.

Bathorys Daughter wrote:. . . It's like anything else, procedures will be put in place for safe operation. After all, even in a car today you are sitting on gallons of highly flammable and potentially explosive fuel. Over the years methods were developed to make the system reasonably safe. At least with air, you're not likely to burn to death should it blow. Heck, all sorts of bad things can happen with home use tanks of LP gas. There's a huge bomb waiting to go off, but they rarely do. Low pressure, yes, but very explosive fuel. At least the explosive-due-spark thingy isn't a real problem with compressed air.

Hollywood hasn't yet heard about these safety measures. . . . WARNING: TV Tropes--Every Car Is a Pinto

My mom bought a Leaf. I can say that EVs train you to think differently about driving, as their optimum acceleration/charge ratio tends to encourage safer habits.

As for safety and comfort, the Leaf feels like any other car. But EVs are a new machine: They're not as different as a carriage or a bicycle from a 20th Century automobile, but it helps to realize they have parameters that aren't going to compare neatly with IC. Comparing them to one another makes way more sense.

More EVs are around, like the Ford Focus and the Coda. A diary at the lefty political blog Daily Kos today has quite a run-down. The comments range from excitement to skepticism over transferring the emissions to the grid: http://www.dailykos.com/story/2012/09/2 ... issan-Leaf

My own feelings on emissions is... EVs are a good start. Adapting our tech toward renewables is way smarter than pretending it can't happen.

bmonk wrote:Hollywood hasn't yet heard about these safety measures. . . . WARNING: TV Tropes--Every Car Is a Pinto

In fact, Pintos did not explode

Audi 5000s did not uncontrollably accelerate.

Toyotas don't either.

The Mustang II had the same chassis and the same fuel tank as the Pinto. How many of those did you hear about exploding?

In the case of the Audi and Toyota "uncontrollable acceleration" claims - there is not a car on the road which has an engine that can overcome its brakes (assuming that the brakes are in good order).

(Well - let me hedge that a little - nothing up to and including a 500 HP Mustang that Car & Driver tested. Certainly not an Audi 5000 or any Toyota.)

Cars do not explode. There is not an explosive mixture inside the fuel tank. (Again, i have to hedge just a bit - if it sits and cooks long enough to set up a BLEVE situation, a car could explode. However, that is both unlikely and wouldn't happen instantly, as shown in movies.)

BLEVEs

Fairportfan wrote:

bmonk wrote:Hollywood hasn't yet heard about these safety measures. . . . WARNING: TV Tropes--Every Car Is a Pinto

In fact, Pintos did not explode

Cars do not explode. There is not an explosive mixture inside the fuel tank. (Again, i have to hedge just a bit - if it sits and cooks long enough to set up a BLEVE situation, a car could explode. However, that is both unlikely and wouldn't happen instantly, as shown in movies.)

BLEVEs

Mythbusters have (has?) explored this trope and I believe found that under ordinary situations it's damn near impossible. I think they had to use a tracer round at a fair distance to make anything happen.

If I could cruise YooToob from work I'd stealth insert the clip from "Top Secret"...

When I was talking about explosions, I was referring to steamers from the turn of the last century. The Stanley twins formed a company which used steam-powered engines as the drivetrain for their autos. The two greatest drawbacks for the steam engine was the size of the boiler and needing a reservoir of water. Imagine a Smart fortwo with an F-150 bed in back - just for the steam engine and the water reservoir.

jwhouk wrote:When I was talking about explosions, I was referring to steamers from the turn of the last century. The Stanley twins formed a company which used steam-powered engines as the drivetrain for their autos. The two greatest drawbacks for the steam engine was the size of the boiler and needing a reservoir of water. Imagine a Smart fortwo with an F-150 bed in back - just for the steam engine and the water reservoir.

Except, of course, it wasn't:



As to explosions: there has never been a documented case of a Stanley boiler exploding in (normal) use.

(I say "normal", because i recall reading about an explosion involving a special car built for a speed record attempt ... however, that one occured after the car went endo, came apart, and the boiler was thrown several yards; also the multi-layer piano-wire wrapping of standard Stanley boilers had been omitted to save weight.)

Fairportfan wrote:

bmonk wrote:Hollywood hasn't yet heard about these safety measures. . . . WARNING: TV Tropes--Every Car Is a Pinto

In fact, Pintos did not explode

Audi 5000s did not uncontrollably accelerate.

Toyotas don't either.

The Mustang II had the same chassis and the same fuel tank as the Pinto. How many of those did you hear about exploding?

In the case of the Audi and Toyota "uncontrollable acceleration" claims - there is not a car on the road which has an engine that can overcome its brakes (assuming that the brakes are in good order).

(Well - let me hedge that a little - nothing up to and including a 500 HP Mustang that Car & Driver tested. Certainly not an Audi 5000 or any Toyota.)

Cars do not explode. There is not an explosive mixture inside the fuel tank. (Again, i have to hedge just a bit - if it sits and cooks long enough to set up a BLEVE situation, a car could explode. However, that is both unlikely and wouldn't happen instantly, as shown in movies.)

BLEVEs

Pintos didn't explode, but they did leak gas in rear-end collisions and had several fires start, all for want of a 2-inch-thick piece of plastic over the bolts that would penetrate the gas tank (studied that problem in a High School class). And the problems with the Audis and Toyotas wasn't so much "uncontrollable" acceleration as "uncommanded" acceleration, followed by people freaking out.

Honestly, the track record of the "average American driver" when it comes to the unexpected makes me realize that, neat as a flying car would be, most of us couldn't handle the addition of the third dimension to our driving needs.

Dave11 wrote:Pintos didn't explode, but they did leak gas in rear-end collisions and had several fires start, all for want of a 2-inch-thick piece of plastic over the bolts that would penetrate the gas tank (studied that problem in a High School class). And the problems with the Audis and Toyotas wasn't so much "uncontrollable" acceleration as "uncommanded" acceleration, followed by people freaking out.

Honestly, the track record of the "average American driver" when it comes to the unexpected makes me realize that, neat as a flying car would be, most of us couldn't handle the addition of the third dimension to our driving needs.

In the one Pinto-related case i know of where criminal charges (as opposed to civil, where the standard of proof is lower) were files - in Indiana, i think - it turned out that the Pinto in question had been hit from behind so hard that it was folded at about a forty-five degree angle and that the gas cap had not been on the car, (In fact, the cause of the wreck was the driver realising that she had just left the cap behind after pumping gas and slowing/stopping quickly in traffic to make a U-turn, right in front of a non-alert driver.)

And, as i said - the Mustang II, with exactly the same chassis, was never reported to be prone to such problems.

As to both the Audi and the Toyota, the claims (and the general belief) was that the cars would suddenly surge forward with no warning, and would do so so powerfully that they could not be stopped.

Indeed, in the case of the Audi, the problem was eventually determined (after the PR damage had been done and Audi had discontinued the car) to have been that it was possible for an unusual circumstance to raise the idle speed by a moderate percentage, leading to the car seeming to lunge forward when shifted from "Park" to "Drive" without the brakes applied. This would lead to the idiot who hadn't had his foot on the brake jabbing for the brake in a panicky manner ... but - guess what? - the pedals in the 5000 were slightly offset from the centerline of the driver's seat.

Which led to the foot landing on the accelerator, not the brake.

Which led to the reports of "I was pushing the brake as hard as I could and it just kept speeding up!"

(In fact, it was determined that there was an almost exact inverse correlation between number of miles driven in the Audi and likelihood to report "uncontrollable acceleration".

(The VW Karman-Ghia had a similar layout oddity - since the vehicle was wider than a Beetle, but built on the same floorpan, the pedals were offset slightly to the right from where you might expect them to be.)

ShneekeyTheLost wrote:

Bathorys Daughter wrote:Oh, and being able to recharge it in a few minutes.

The MiEV recharges in a half hour. Besides, you generally recharge it when you're asleep.

Bathorys Daughter wrote:I can't see buying one just for tooling around town. Whatever I get has to be able to be my all around vehicle. Multiple cars is not really a viable option for me.

Me either. Which is why I'm excited about the Model Z. 300 miles on a charge, which is about as far as you'd get on a tank of gas. Charge it up when you get home. About the only thing you might have a problem with is if you want to take extended trips.

And all of this is why I'd have to go the multiple car route. While an electric would be fine for regular driving around town (assuming we had a place to plug it in at night), it wouldn't do us any good outside of that. If I want to go visit my grandmother, we'd be driving 192 miles to see her (well within the proposed 300 mile range of an electric car). However, we wouldn't be able to stay with her since she lives in a retirement community that gave her a one-bedroom apartment. We might be able to stay with my aunt and uncle who live in the same city (in my grandmother's old house), but plugging in the car to recharge it overnight could prove difficult since it's recommended that you use an outlet on its own circuit when pluging into a normal household outlet...otherwise you could trip the circuit breaker. If we had to stay at a local hotel, plugging in could prove even more difficult. Either way, we'd be driving an additional 2-5 miles to get to the overnight location. If plugging in isn't an option at those places, then we're S.O.L. for our return drive home since we've already used almost 200 of our 300 miles for a single charge.

Even for our more "regularly occurring" roadtrip out to my parents' land in east Texas we'd be cutting it pretty close since that's a 140 mile trip in one direction...and there is definitely not a recharging option at their place out there. We celebrated when they got central heat and air in the little farmhouse on that property...so outdoor charging is out of the question!

I get where some people are coming from on the "can't afford multiple cars" front, but I'm fortunate enough to have a husband who came with a car (no car payments), and I'm nearly finished paying off my current vehicle. Replacing his >200K mileage Honda with an electric is a do-able thing...but we'd have to keep my IC car for trips.

It occurred to me that one way you could get by with just an electric car would be to rent a regular car when you have to take a trip. While it would be expensive, it would still be a heckova lot cheaper in the long run than having two cars just because you need to take a long trip on occasion. I think that's what I would do anyway.

OTOH, the lack of places to plug one in could be managed if the car had a small on-board, very quiet engine and generator. That way you could recharge it overnight no matter what. Probably something around 5 HP would do. I've seen articles on small 2-3 KW generators that are very quiet and quite portable. With a larger gas tank, one of those might even work out.

Dave11 wrote:Pintos didn't explode, but they did leak gas in rear-end collisions and had several fires start, all for want of a 2-inch-thick piece of plastic over the bolts that would penetrate the gas tank (studied that problem in a High School class). And the problems with the Audis and Toyotas wasn't so much "uncontrollable" acceleration as "uncommanded" acceleration, followed by people freaking out.

Honestly, the track record of the "average American driver" when it comes to the unexpected makes me realize that, neat as a flying car would be, most of us couldn't handle the addition of the third dimension to our driving needs.

Not as bad as the Crown Vic used as a standard model police cruiser.

The gas tank was under the trunk, but not properly reinforced. When in a rear-end collision (like, say, a drunk hitting the cop from behind while he had pulled someone else over), the fuel tank would warp and be pushed into the passenger cabin, igniting the remaining fuel, and frying anyone in the passenger cabin of the vehicle at the time. In Texas, we would call 'em "BBQmobiles', because over thirty recorded police deaths occurred as a direct result of this fault before Detroit even acknowledged the fault and issued a recall.

Bathorys Daughter wrote:OTOH, the lack of places to plug one in could be managed if the car had a small on-board, very quiet engine and generator. That way you could recharge it overnight no matter what. Probably something around 5 HP would do. I've seen articles on small 2-3 KW generators that are very quiet and quite portable. With a larger gas tank, one of those might even work out.

That sort of defeats the purpose of the electric car, since the engine driving the generator would consume fossil fuel and produce pollution locally, defeating the main perceived virtues of an electric car.