By Oedipus Wreckx-n-Effect
Wherein I tackle the idea of hydrogen fuel cell technology in private vehicles.
For the past few years, Hydrogen Fuelcell technology has been making the news in regards to personal transportation. Regardless of how long fuel cell technology has been used in the space industry, the media treated it like a futuristic Godsend for personal vehicles. I recall there being plans drawn up for refueling stations in California, even. But the Bear State is fond of making whatever promise they can to skim as much money from its people.
See the High Speed rail fiasco.
When I first heard of hydrogen fuel cells being used in vehicles, I was too young and immature to have much of an opinion. Back then, I was still cruising around downtown and hanging out with Sturgeon to care about motor vehicle trends. Those nights were spent talking trash about HK products, doing blow through rolled up Benjamins, and dozens of questionably legal Polynesian women.
I'll be approaching this issue regards to efficiency, safety, production, and storage of many elements. We'll first discuss what hydrogen is.
The Wiki gives a ton of great information. Most of you will know the basics. It's a gas at STP, contains a single valence electron in it's 1s shell (“shell” or cloud of probability derived by shrodinger's blah blah blah Physical Chemistry nonsense, don't make me do that derivation again). It was first artificially made by a guy named Cavendish, and is found naturally as a diatomic molecule.
This diatomic molecule also really likes to explode if it gets near an energy source. H2 combustion is well documented, and releases 286 kJ/Mol.
In fact, it can undergo combustion at as low as 4% concentration with air. That's low.
Hydrogen's low molecular weight makes it the lightest gas around. This was capitalized during the second to last turn of the century, where mighty Zeppelins pushed through the sky like herds of giant sky manatees.
Large enough to fit Colli-man's collection of miss-matched socks
Germany loved these guys, and for a while they were all the rage in luxurious travel. Indeed, it was certainly the 20th century now! We had Airships, the Haber Process that was fueling an industrial revolution, and all of physics was completely solved! Thanks, Maxwell!
(And then came the ultraviolet catastrophe, but that's another topic.)
However, I mentioned above that hydrogen is extremely flammable at even very low concentrations within air. This fact really sunk the airship industry with a certain spectacular disaster.
German Engineering, or Masonic Zion plot?
It's easy to skip over this picture entirely. We've all seen it so many times (Unless you're one of my tutoring students, who look at me like I've got two heads when I mention it. “The hinda-what?”).
But, this was the end of an era. Static charges ignited the hydrogen sacks that kept the big rigid frame afloat. And though we could have used Helium, a much more stable gas, the damage was done. No one would step foot near a rigid airship again.
(Also our world's supply of Helium is finite and diminishing very very quickly. It would be wasted in airships. But again, another topic another time)
Let's get back to the Hydrogen Fuelcell. What exactly is it, and how does it work?
The basic model is shown below.
This diagram is for a Proton Exchange Fuel Cell. The proton here is simply a hydrogen that's been stripped of its single electron. A fuel cell works by having very special membranes carefully constructed to permit the passage of a positively charged ion, but not the negatively charged electron. This travels through another path, leading to a voltage across the cell. This voltage can be used to power any electrical device.
This is an oversimplification of how the device works, but it's a start.
The benefits of such a device include the shear efficiency that it can have. When properly insulated and owing to proper low-resistance connections, these devices are pushing out efficiencies twice that of internal combustion engines. Which, despite what many places attempt to sell you, are actually quite thermodynamically efficient. These proton based fuel cells have great cold-start characteristics and energy density. Their outputs can actually be very high.
Indeed, these fuel cells are efficient at all power outputs as well. Their efficiency does not vary with flow of fuel source either.
Their temperatures can be as low as 80 degrees C. However, usually they are kept above 100 degrees C because steam is far more manageable than liquid water byproduct.
So with all of this information, you're probably wondering why haven't we started putting these into all sorts of places. This post is about personal vehicles, however, and I'll get right back to that.
No. I disagree completely with them being used in personal vehicles.
While I love fuel cells as a power device, their use in personal vehicles is greatly limited. One of the biggest engineering hurdles is the flammability and storage of pure hydrogen. Since hydrogen has such a low molecular weight, to obtain a large enough amount to power a personal vehicle would require a very high pressure container. If you remember back to your Chemistry classes in high school, you may remember the Ideal Gas Equation. Hydrogen is pretty close to an Ideal Gas. As close as you'll get, really. The Ideal Gas Law, in actual use, is only about 84% accurate when used to guess thermodynamic systems. For hydrogen it's much higher.
PV=nRT, where n is the number of moles. Keeping everything but Pressure and number of moles the same, to increase the number of moles directly increases the pressure. And H2, having a molecular weight of 2 Grams per Mole, would require a ton of moles to get a decent amount of the gas.
A very high pressure container of pure hydrogen gas in a vehicle that routinely travels at 70 mph. Which is statistically guaranteed to be in an accident in its lifespan.
The Germans are watching this and going “Nein Nein Nein!”
According to this nifty search, over 3,000 people die per day in the US due to vehicular collisions. Ouch.
However, this issue is the first to be solved. The introduction of Metal Hydrides have solved the storage issues. Metal Hydrides act as chemical sponges for Hydrogen gas (H2), binding the molecules inside their chemical structure. These metal hydrides are usually used as powders, where the hydrogen is then pushed through to store. To release the hydrogen, the metal hydride must be heated. The rate of diffusion is directly related to the temperature at which the metal hydride is heated, and thus the fuel rate into the fuel cell can be varied by varying the temperature of the metal hydride.
Metal hydrides can absorb 2 to 10% H2 usually, but better compounds are being produced to increase the number.
This is good, because it gives us a safe way to store hydrogen gas for fuel cells.
This is bad, because the fuel delivery rate is much lower, and metal hydride fuel cells are, at their very best, 1/4th as powerful as their PEM brothers. At worst, they are 1/50th.
But this is the best we can do in a vehicle. No one wants pressurized hydrogen canisters on the highways. Hell, most of the time you need special clearance and big signs to transport the stuff. And imagine the safety concerns for the EMTs and Paramedics during a car crash. Even if the tank isn't ruptured, no EMT or Paramedic would risk their lives until the wreckage was cleared.
When I was going through my EMT training, they made it very clear that it doesn't matter if people are bleeding out in front of you. If you go in while it's still dangerous, you're only being a liability to your fellow EMTs, Firefighters, and police.
But let's ignore the low power outputs of these MH Fuel Cells. What other issues do we have?
Well, the fuel cell itself must be created using some very interesting techniques and materials. The biggest expense would be the platinum. Other catalysts are needed as well. As well as a very special proton-permeable membrane.
To function, the membrane must conduct hydrogen ions (protons) but not electrons as this would in effect "short circuit" the fuel cell. The membrane must also not allow either gas to pass to the other side of the cell, a problem known as gas crossover. Finally, the membrane must be resistant to the reducing environment at the cathode as well as the harsh oxidative environment at the anode.
This system includes electrodes, electrolyte, catalyst, and a porous gas diffusion layer. The rate of reaction will be dependent also on how quickly the water vapor product can diffuse through the porous material and out of the system. A system can have a lowered efficiency if the fuel cell is too dry or too wet. A balance must be met.
And while yes, all of these situations can be worked around, it all comes at a heavy price. Currently we are using 30 grams of platinum in vehicle sized PEM fuel cells. This number will be going down once different catalysts are created, but the cost of these vehicles still pushes up to $50,000. The cost will go down, like any technology.
I've yet to speak about where we obtain this hydrogen gas from. The easiest way to obtain hydrogen gas is via the electrolysis of water. H20 + An Electric Current → H2 + O2, essentially (it's not balanced, I know this.)
But that electric current must be created as well. This usually comes from the electric grid, which is still, depending on the state, a majority coal-burning.
Natural Gas reformation is another way to obtain Hydrogen gas, and is the most common way we currently use. It's the cheapest as well. Synthesis gas, a mixture of hydrogen, carbon monoxide, and a small amount of carbon dioxide, is created by reacting natural gas with high-temperature steam. The carbon monoxide is reacted with water to produce additional hydrogen.
The other common ways are via fermentation of biofuel stocks (which is a long process without a great yield) or liquid reforming, which is really unfeasible in large quantities.
The only way to obtain large amounts of hydrogen is via natural gas reformation, and that's still technically a fossil fuel source. So why were we going with hydrogen fuel cells again? To rid ourselves of dirty, dirty fossil fuel? Well shit.
So to sum this up, the only way to safely use hydrogen as a fuel source in a moving vehicle would be by using metal hydrides, which require energy to access the stored hydrogen. This stored hydrogen flow rate is lower than standard PEMs, and results in a lower voltage, which in turn leads to a lower power output for the vehicle. More research and development must be done to find proper catalysts that can be made at a low cost, and production methods must be worked out to create the membranes more cheaply. All of this is held up by our hydrogen production systems.
PEM fuel cell technology is awesome and I love it to death in many many situations. But vehicles isn't one of them.
I may read about more advances in the near future that would change my opinion completely, but I would be surprised.
Below I've added a problem out of my heat and mass transfer book (Incropera, 7th edition).
We have thread about old Soviet cars and Americal cars (that also tend to be about older and top models). This thread is general thread about any cars - new and old, racing or for work. Car news also can be posted here.
I begin this topic with this -
Studebaker Sceptre, created by italian Sibona-Bassano company. Never produced, it is a hell of a looker.
I thought it was disgraceful we had a thread on Russian race cars, and other cars, but not one on American muscle cars and race cars, IE the best cars.
Over the weekend I'll put a little write up on the GTO and why it kicked off the musclecar, and why the Mustang was an overrated econo box for girls until the 67 model, more akin to a nova then a truly great car like a Pontiac GTO.
My thoughts on why the muscle car era was teh awesome.
The reason 64 to 73 was one of the most interesting era for American cars, is they went a little nuts on how much power they started putting into cars, and all the GM brands for the most part still had their own engine types.
The birth of the muscle car era started in 1964 when John Delorean, Jim Wangers and Pete Estes snuck the GTO option on the 64 mid-size Pontiac Tempest/Lemans platform that was based on GM A-Body platform. There were a few reasons it had to be snuck in, all mainly the fault of GM head executives being stodge old fogies. They had come up with two policies that caused boring cars. The first was their decision to pull out of any GM sponsored racing and the ban on developing performance parts. They also had a ban on putting motors bigger than 330 cubic inches in mid-size cars.
The sad thing is GM had a thriving race scene and a set of dealers and race teams using their products. Pontiac and Chevrolet in particular had really bumped up their market share through their winning race teams. They were doing crazy stuff like Swiss cheesing frames, producing aluminum front ends (hoods, fenders, bumpers), and producing multi carb manifolds and there’s more I’m sure I’m forgetting. Then BAM, in the span of weeks GM killed it all off in 63.
The heart of GTO option on the Lemans was the 389 cubic inch V8 used in Pontiac full size cars. The V8 was rated a 325 horsepower. The biggest V8 the car came with normally was the 326. The GTO option also included the choice of a close ratio four speed Muncie transmission, and heavy duty suspension and brakes. It could also include Pontiacs Safe-T-track limited slip differential with gear ratio choices of 3.23, 3.55, 3.90, 4.10, and if I recall right, 4.56. The name was strait up ripped off from Ferrari, by Delorean. You could also order the package with triple carburetors, also known as tri-power, and it upped the engines horsepower to 335.
GM and Pontiac found out about it, but Wangers had gone out and showed the car to some big dealers in the Detroit area and they already had big orders so GM corporate, and Pontiac let it be produced, the general manager told Delorean he would have the last laugh because there was no way they could even sell the 5000 that had been authorized, and Pontiac would have to eat the loss on inventory they couldn't sell, and it would be his ass. It sold more than 32,000 units, as a really un advertised option, so Delorean and Estes won the day, and the ban on big engines in mid size cars was lifted, and the GTO became its own model, still based on the Lemans/tempest platform, but with no small engine choices.
The other GM brands caught up with their own special models in 1965, Chevrolet with the SS 396 Chevelle, Oldsmobile with the 442, and Buick with the GS. GM still put a size restriction on motors and their A-Body mid-size models, but it was now 400 cubic inches, and all the brands had motors that could be grown well past this and already had been and were used in the full-size car lines. Even this restriction would be pulled in 1970 because other major brands were stuffing huge motors in mid and even the newer smaller cars and GM was losing out.
Ford and Chrysler and even AMC didn't just sit back and watch GM reap the reward, Ford had come out with their ‘Pony’ car the Mustang, in 1964, and it was also a huge success, but it was no performance car, even with the top of the line V8 option, a GTO would eat it alive, handing and acceleration wise. Ford also had mid-size cars with large V8 options, but none that had been packaged like the GTO and they were light on good large V8s in the early 60s, plus their mid-size cars were ugly as hell. The Mustang would grow into its own later in the 60s, in particular, when Carol Shelby started playing with them. They never had a great mid-size muscle car that wasn't ugly though.
Chrysler had cars that could be considered muscle cars, but before 68 they were all so ugly, no one but weirdos drove them. They did have some very powerful engine combos, and they really hit the scene hard with the introduction of the cheap as hell but big engine powered Plymouth Road-Runner in 1968, you could buy a very fast Road-Runner for a lot less than you could even a base model GTO. For a classier Chrysler they had their Plymouth GTX line, and Dodge had their beautiful Charger. The Cuda got an update in 1970, so it wasn’t really really ugly anymore, and the same platform was used to give Dodge the Challenger. These cars fit more into the pony car scheme though. The main point is Chrysler produced ugly cars until 1968.
GM would jump into the pony car scene in 1967 with the introduction of the first gen F-body. Chevrolet got the Camaro, and Pontiac got the Firebird. These cars were introduced with engine options up to 400 cubic inches, though, when they got a 396, or 400, they were slightly detuned so the mid-size cars still had an ‘advantage’, there was just a little tab that restricted the secondaries on the quadrajet carb.
The whole thing came crashing down and by 1973, the muscle car was all but dead, and the US car industry was in a slump it would not recover from until the late 80s, also when the muscle car returned in a weird way with the Buick Gran National. While it lasted the muscle-car era produced some iconic cars, and some very rare but interesting ones. Most of them looked pretty damn cool though, and by now, they are very rare to see as daily driven cars. They exist; I pass a 68 SS Camaro all the time. Now even a base model muscle car or pony car that's rusted all to hell can be more then 8 to 10 grand, and you will spend triple that making it into a nice car.
1970 was probably the peak year, and some very powerful cars came out that year and that year only. Chevrolet offered the SS Chevelle with the LS6 454, pumping out 450 HP. Buick, Oldsmobile and Pontiac all had very high horsepower 455 cubic inch V8s in the GSX, 442, and GTO models. Government safety restrictions, smog restrictions that required a lot of crap to be added to the engines, and high insurance prices all worked to kill these cars, and the final straw was the gas crisis. The US Auto industry was a barren waste land unless you liked trucks, until about 1986.
The cars never lost popularity though, but their worth has fluctuated a lot. You could buy just about anything in the late 70s and early 80s, and you could gate rare stuff a low prices, but by the late 80s the collectors had started getting into muscle cars and the prices went crazy. No, unless you want to spend a lot of money, you’re not going to be driving around a classic car from that era. On the upside, the aftermarket parts scene has gotten so extensive, you can build a 1968 Camaro, or 1970 Chevelle almost from scratch, since the body shell and just about all the body panels are being produced. You’re looking at about 14 grand just for the body shell of a 1970 Chevelle, from there you looking at a huge chunk of change to build it all the way, but it could be done. I suspect they are used to put a very rare, but totaled cars back into shape.
It’s nice to be helping with the restoration of one of these cars, without being tied to the cost. I can have fun taking it apart, and putting it back together without worrying about how I was going to fund it. I also have more tools for working on cars than my father in law, and know more about GM cars, so I’m appreciated, and that’s nice. I just with the owner was willing to upgrade the thing a little, you can really go a long way to making an old muscle car handle and stop well, and be more reliable and safe with upgrades not much more than rebuilding everything dead stock, and putting upgraded suspension on a otherwise numbers matching car really doesn't hurt the value, especially if you put all the stock shit in boxes and save it. I’m not paying for it though so it is of course his call, and putting it back together stock is easier in most cases. I really wish it was a 68 GTO because, man I still know those cars, and every time we run into some stupid Chevy thing, I’m like, man, Pontiacs are so much better, and I get dirty looks. BUT THEY ARE!!!
Anyway, I said I would write something up, and there it is.
Hopefully we have a few guys in here who dig on American Iron and will post about the cars they loved, and yes, I mean in that way,
This thread will be about Soviet cars, racing vehicles and SRS BSNS cars. More photos, less text!
Moskvich 404, 1954.
Moskvich 407 Coupe