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E85 - a good way to help reduce CO at the expense of mileage (ethanol has about half the content of energy per gallon of gasoline). Similar energy efficiency concerns with ethanol production as hydrogen - takes energy to refine. May increase *-aldehydes, known carcinogens.

Why are all the car companies pushing on hydrogen and fuel cells? Well, that's the $1M question, ain't it?

I can only assume it's the latest in a series of misinformation and misunderstanding that hydrogen is really powerful, it's clean, it is easily made from water, it's renewable, and the exhaust from a fuel cell vehicle is only water.

Yet there's significant problems with all of these. Hydrogen is powerful - if you don't care about volume (like the Space Shuttle). But having to carry around a fuel tank that occupies 90 gallons ain't too practical. Fuel cells that use hydrogen as the primary fuel (all fuel cells are actually very similar to batteries - a cathode and an anode work in a medium to combine chemically and in the process give off electrons) are clean - at their source. The making of hydrogen is dirty (actually more carbon emission per kg of hydrogen produced from petroleum, 98% of hydrogen production techniquest today, than is emitted by burning a gallon of gasoline). It can be made from water, but not easily (70% efficient, it takes a bunch of electricity to produce a tankful of hydrogen).

Still leaves the question of why unanswered.
 

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solsticeman said:
Why are all the car companies pushing on hydrogen and fuel cells? Well, that's the $1M question, ain't it?

I can only assume it's the latest in a series of misinformation and misunderstanding that hydrogen is really powerful, it's clean, it is easily made from water, it's renewable, and the exhaust from a fuel cell vehicle is only water.
Maybe this is based on misunderstanding…. The misunderstanding of the public at large about the inefficiency and impracticality of the fuel cell vs the possibility with regular battery/electrics.

I am sure if GM announced a high tech battery and a new electric car that ran on batteries, everyone would think it was the same old song and dance, with limited range, long recharge times, etc. However, if GM announces a new fuel cell vehicle, that burns clean, no fossil fuels, produces electricity immediately on demand, suddenly the negatives of the old battery powered electric car are gone AND people think we are shedding our dependence on foreign oil (even if we increase it due to the need to create hydrogen).

If that is the thinking, GM’s decision to pursue fuel cells could be as much a marketing decision as anything. People like the idea and seem open to buying the technology, so why not provide it to them. Sure, another technology may be better, but if they think its bad and don’t buy it, GM taking time and money to develop it would not be a good business decision.

That may not have anything to do with it, but it’s a possibility.
 

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There are a few things that must be tackled before we as a society embrace alternate fuel/propulsion:

1) Performance. 0-60 mph in 10 seconds. Why do we not embrace diesel today? It's got a significant improvement in fuel consumption, on the realm of an additional 10 miles per gallon for comparable sized vehicles... but everyone bitches about the performance of diesels. Everyone also talks about emission performance, but really, diesels have come a long long way toward being comparable to gasoline. We (in the US) won't even give diesels a second look. We laugh at them in anything other than trucks.

2) Seating minimum of 4, preferably 5, or similar in size and comfort of at least a Cobalt. Luggage and storage similar.

3) Reasonable method of re-fueling or re-charging. Practical timing (say maximum of 10 minutes to re-fuel) or practically-useful scheme (ICE backup, with overnight vehicle charging... whatever works).

4) MINIMUM of 300 miles between re-fueling or re-charging, with 15% margin (this means 350 miles from full to sputtering, walk-home empty). Many of these fuel cell vehicles report a range (like the HydroGen3) of, say, 250 miles - but you can't use the whole mileage - the practical mileage is more like 200-210 before you really should be looking for a re-fueling station. So when you see a range for a fuel cell vehicle, always compare it to 350 miles range - typical of what you might get in a normal passenger vehicle.

The charging is not as much of a problem as long as the stations to charge are practical (for an electrical vehicle). It's an energy-in equation, V*A=watts, there's so many watt-hours you need to pack in... at practical voltage and amps (240 VAC at 25 amps, for example), currently the charge time for any vehicle regardless of battery type is about equivalent to 1 or 1.5 minute per mile of driving.

With gasoline, you can pump about 45 Megajoules in 15 seconds or a re-charge rate of about 3 MegaWatts. Electrically, unless you can really increase amperage, it's really only practical to plug into the wall and regarge at about 3 KiloWatts, but multiple electrical ports can increase it. However, just think about your service amperage for your home (100 amps? 150 Amps? 200 amp service?) and realize that re-charge at home is possible but you're going to have to deal with large chunks of time for full recharges. It starts to become practical if you recharge at 30 seconds per mile driven - you get home, dock your electric vehicle and walk away. I know my vehicle at night is usually available for recharging for at least four hours every day...

Service stations could have "ultra-charge" stations that recharge at 10 or 20 kilowatts, provided the bugs of charging at that rate are worked out, but it's definitely possible - we already know how to distribute hi-power electricity safely and efficiently.

Check out "MeVictory" here:
http://www.reveo.com/press_mevehicle.htm

and these metal-fuel cells here:
http://www.3nw.com/energy/resources/metal_fuel_cells.htm

These fuel cells are theoretically reversible. Similar to electrolysis, for a Zn fuel cell, the theory is you allow Zn to combine with atmopheric oxygen to liberate electrons and get Zn-oxide. Pump back in electricity, and theoretically electrolyze the Zinc Oxide back into Zn and O2, (yes, it's a lot like hydrogen electrolysis) at some efficiency. I emphasize theoretically, because there are physical problems that require research to overcome before they become truly reversible.

But as long as the autocompanies all are stuck on this "hydrogen highway" bullcrap, metal fuel and batteries still remain with the meager research budget of electronics companies in search of a phone battery that doesn't need to be charged every day.
 

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When we bought our last vehicle, I tried to talk my wife into the VW tdi engine. With Bio-diesel filtered clean there is very little of the smell and emmisions associated with a standard diesel in a big rig. (still CO2 but can we get around that?) There is not enough bio-diesel available to run everybody's car, but it could make a dent in the need to support the middle east. My wife wouldn't go for it. She could not get over the thought of owning a diesel.
 

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CO2 is not something you can get around. For every gallon of diesel you burn, 10.1 kg (about 22 lbs) of CO2 is produced - no getting around it at all. The only way to control CO2 emission is to either capture and bind it (not practical, but it's what was done on the Apollo moon missions when you only had to deal with human respiration amounts), or burn less fuel - end of story.

Biodiesel is a pretty good alternative, if you can get it. I've seen it as reasonably more expensive than petroleum diesel, and the mileage is slightly worse but still better than gasoline (biodiesel has a little less energy per gallon, but the efficiency of the diesel cycle more than makes up for it). The lack of sulfur is very kool, though.
 

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22 lbs, are you sure? Because a galon of diesel fuel doesn't even weigh 22 lbs in the first place. Just seems kinda high to me. Because I know a gallon of regular unleaded gas is only about ~6 lbs.
 

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Good explanation of the practical realities that we really need to see. Even with electric vehicles, overnight recharging can become problematic if you are not home on a particular night. High charge service stations would have to be set up, or hotels and such would have to add a charging service. Although, regardless of what alternative energy is used, a complete infrastructure to distribute the energy would be needed.

A lot of people predict diesels could make a comeback, but there is some legislative hurtles in their way. Currently, 7 states (might be 5, but I am fairly certain it is 7) have basically outlawed diesels due to their emissions. NY and CA are two of those states. The arrival of low sulfer diesel fuel in 2007 should allow the engines, at least the most modern ones, to meet the emissions regs in those 7 states. However, until that time, I do not think you will see much of a push from automakers into diesels. After that time, a couple models may show up to test the waters. The real question is, will the public embrace them?
 

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brentil said:
22 lbs, are you sure? Because a galon of diesel fuel doesn't even weigh 22 lbs in the first place. Just seems kinda high to me. Because I know a gallon of regular unleaded gas is only about ~6 lbs.

Yep. CO2 consists of an atom of carbon and two of oxygen. A gallon of diesel has about 6 lbs worth of carbon atoms (hydrocarbon pariffinics of the C10H12 to C20H22 length, most of which by weight is carbon, along with some aromatics and other compounds, again mostly carbon by percent weight).

For every 6 lbs of carbon, when burnt into CO2, there's 16 lbs of oxygen that came in through your intake for combustion. Total, about 22 lbs.

Surprising, isn't it?
 

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Ok, yeah you're right. I wasn't thinking about the number of O atoms that would be added to the amount of diesel fuel used.
 

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solsticeman, you really have this stuff down, and the zno2 cells are interesting, but I think there are some clarifications here that help make more sense of why everyone is so keen on hydrogen.

First off, most of the points discussed here have been exhaustively studied by several research institutues and groups, including Argonne Nation labs, which has lots of this information summarized. http://transtech.anl.gov/v2n2/well-to-wheel.html

It is pretty much concensus that the first source of hydrogen will be natural gas, not petroleum. And even if the hydrogen will need to be liquified (which hopefully it won't with progress in those metal-hydrides), total greenhouse gas emissions would be much lower converting NG to hydrogen, than with even hybrid-powered gas ICE powered cars. The big key here is the U.S. is projected to have more than enough NG production to meet all our transportation and power needs for the forseeable future, and this would get us off the petroleum addiction that will only get worse with time. And of course when people think hydrogen, they are thinking about the future. GM might say 2010, but realistically for the U.S. market (things may be different for GM in say China) everyone is really thinking 2015 and beyond. If things go as projected, renewable energy including PV and wind should be come respectable components of overall energy production. None of this is given, but it is likely that by the time fuel cells vehicles would be prolific, electricity would be considerable cleaner. And from this perspective, electrolysis can be 100% clean (yes it will always have losses).

Second, yes fuel-cells are only say 50%+ efficient, and electric motors are only 80-90% efficient, but TOTAL well-to-wheel efficiency is still HIGHER than in hybrid powered-gasoline-ICE's. Let's not forget we're up against the 2nd-law and the Carnot efficiency in ICE's and resulting cars average well-to-wheel efficiencies of <15%! So this is actually an advantage for all electric vehicles. Any electric vehicle, fuel-cell or otherwise, is also easily amenable to recapturing braking-losses for added efficiency.

Finally, everyone can argure about these things until they're are blue in the face, but the fact it is hard to get people to change their lifestylles and their expectations. The main reason hydrogen is so favorable over batteries is the fact that the refueling is fast. You can argue about 30s vs. 1.5 min pwer mile, and what's reasonable and not reasonable for charge times, but for the vast majority of people, they want something that fuels as fast as a gas car, and that lets you take extended trips. How are you going to convince the public to accept the inconveiences of a different refueling process, if you can't even convince people to drive station wagons and minivans instead of SUVs? Hydrogen offers that convenience. The ZnO cells, as they still rely on electron transfer via outside applied potential (vs. gas transport for H-fuel-cells) will likely still suffer from these limitations.

Hydrogen isn't perfect, and there is admittedly lots of research that needs to be done for feasiblity. But there is a clear path to viability, and the critics need to look at the big picture. As much as some may malign it, GM's Hywire study is very compelling. GM has finally listened to the EV community and realized outside of the fuel-cell, EV cars cost way less to manufacturer, and offer far superior design flexibilty (fully drive-by-wire, engines in the wheel-well, no more conventional drivetrains, differentials, transmissions required). And GM I would guess has it's eyes on China, which is so early in it's development that it could more easily convince people and industry to develop a hydrogen economy.

But anyhow, I for one would luv a hybrid option on the solstice. I'd give up the trunk for that. I'm part of the crowd that would use this as a commuter car, and just want something that's fun to drive everyday to work. For us, mileage is pretty important. But here GM really invites criticism in that it's hybrid development is really bass-ackwards and there is zero-chance of this ever happening. But heck, i'd be happy with that engine-kill strap on it's selling as its 'Advanced-Hybrid-System' on it's trucks right now. It's no hybrid, but it adds minimal complexity, minimal parts, and could easily be added to the solstice. In fact that's one of GM's excuses for even offering such a cheesy option-- that it's easy to add in volume to all of it's cars. Hey, for $400, I'd add it.
 

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From Solsticeman's impressive research, it seems I have been sold a line of bull with regards to fuel cells, and the arguments against them are persuesive. However the reason that the "hydrogen economy" is being touted and auto companies are researching fuel cells instead of just a better battery is no doubt because of the promise that hydrogen holds in the imagination of the people. General Motors is no doubt hoping to capture government research money that they hope will flow from congress backed by the will of the people. Is it good science or economics? No, but it's what people want, no more oil.

We went to the Moon, not because it was good science or an efficient use of research money, but because at the time that's what the people wanted. Today people want independence from fossil fuels. Practical or not, that's what they want, not just a 10% improvement in their hybrid car, but total independence. It is a dream, and maybe a foolish dream, but once upon a time the notion of flight was a foolish dream, yet there is probably not a person on this board that has not flown.

I don't advocate giving up on battery research, just the opposite, the world can always use a better battery, and I would hazard to guess that there is probably a hundred companies world wide working on a better battery right now. I don't think we have to worry about a lack of battery research, as more and more of our daily life becomes dependent on batteries, the need for better batteries is plain, and the motivation for profit will keep the ball rolling. In time it may be better electrical storage devices that ultimately save us, but the concept just doesn't spark the imagination quite like the notion of cars that don't burn gas and have nothing but water spit out the back.

I'm not saying that Solsticeman is wrong in his asessment of the situation, just the opposite, he is proabably correct, I'm just pointing out the reason GM and many others may be so in love with fuel cells, and to state that perhaps it is research that is valid. Perhaps a battery/fuel cell hybrid car? Use the fuel cell to boost the range of a conventional electric car? Hydrogen fuel cells are only 55% effecient now, but the best ICE are only about 35% effecient (most of the potential energy in the gasoline combustion is wasted in unusable heat), and they will get better. The Wright Brothers '03 flyer only flew a little over 100' and never left ground effect, yet only 86 years latter it was possible to fly completely around the world without refueling, and they are planning to do it again soon, only much faster with jet engines this time!

Bottom line, fossil fuels are going bye bye. The energy demands of the 21st century will no doubt outstrip most of the supplies we have left. We will be forced to switch to something else eventually. Might as well start thinking now about a replacement, and more efficeint energy storage and transfer devices now. Oh yeah, as to the battery recharging problem, why don't we just switch battries on our electric cars at the recharge station like a cell phone instead of waiting for them to recharge? Push, pull click clik, you're back on the road in 5 minutes! Just an idea. Here's to the future! :cheers
 

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AeroDave said:
We went to the Moon, not because it was good science or an efficient use of research money, but because at the time that's what the people wanted.
Actually, all the NASA research provides a lot of practical results for other fields too. I'd say it's one of the most efficient uses of research money out there.
You can search through some of the so-called "spinoffs" of NASA research at: http://www.sti.nasa.gov/tto/spinselect.html
 

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Berkpaul,

I guess I classified nat'l gas as a petroleum product. It's certainly a fossil fuel.

Some hydrogen production also comes from steam reformation of methanol - which is primarily a petroleum product from crude oil.

Estimations of coal reserves at current usage rates (primarily for root-source electricity) is about 250 years. Natural gas is closer to 80-100 years, US based. And that's at current rates.

Aside from that - steam reformation produces CO2 to get H2, about 22kg of it per kg of hydrogen! And a kg of hydrogen is about energy equivalent to a gallon of gasoline. Not counting the distribution part of it (more greenhouse gasses), per energy equivalent of production, hydrogen produces MORE greenhouse gas, minus the small amounts of NOX, CO, HC and Particulates, as gasoline does per gallon.

Compare that with electricity: Coal on the average (most of our electricity today) has about 25 metric tonnes of carbon per produced terajoules (a million megajoules). Working this backward, and an electric vehicle efficiency of around 72% battery-to-road, this works out to around 100 g/MJ of CO2, or about 90 g CO2/km. Compare this to a 30 MPG gasoline engine car of around 185 g/km, and then tell me which is better?

Even working it backward using natural gas reformation and "assumed" better FCV efficiencies of around 40% T-T-W, it works out to close to 300 g/km. So much for that nice, clean, low emission hydrogen.

Aerodave, I've heard the wright brothers and flight argument before - but keep in mind that the Stirling Cycle was discovered decades before the Otto Cycle - and I have yet to drive a Stirling engine car. Right now, we don't know whether the "hydrogen economy" is akin to the otto or diesel cycle, or the stirling cycle.

Math is making me lean toward the "stirling" end of the scale.
 

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Valid point, 2kwk4u, but you could say that The Hindenburg gave poor Hydrogen a bad rap. Nobody seems to think gasoline fumes are explosive, for some reason. What about when that gas tank is sitting near empty? You're pretty much carrying a bomb around at that point.

There was a History channel deal on the Hindenburg recently, and while hydrogen certainly contributed fuel to the fire, the real reason it spread so quickly was the Silver paint used to dope the fabric exterior was practically solid rocket fuel when it dried. That's some fine German engineering there.

But don't get me going on aviation history, I'll talk your ears off.

edit: oops, i posted without seeing page 2, wow, what a lot of info! When I have a hour or two I'll read it and see if I repeated what someone else said! :D
 

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The partial vapor pressure of the gasoline fumes in the space above the tank do not allow sufficient oxygen to exist for combustion. That's why you can put out a match in a pail of gasoline. DO NOT TRY IT THOUGH!!!

In a crash, the only opportunity for explosion is when the fuel tank is ruptured and gasoline gets out and vaporizes and disburses enough in the atmosphere and then comes in contact with the ignition source. Have seen many vids where folks ignite the tank when fueling with a static electricity spark - it just burns, until they shut the pump off, then it just goes out. It burns because when you're pumping fuel in, the gasoline fumes are coming out and mixing with enough atmosphere to burn - but the key is the flame doesn't go into the tank and explode wildly.

People get burned because they panic and yank the nozzle out of the filler - then you spray gasoline all over your car, it burns which creates heat which vaporizes more gasoline which also burns, and the spray from the nozzle gets burning gasoline all over the car and the person refueling...

Now alcohols... THOSE are a problem, and likely the main reason that pure ethanol or methanol are not used as a primary fuel in mainstream transportation. The alcohol vapor above the liquid in a tank full of alcohol IS oxygenated enough to burn - and burning things in a confined area usually are either a) blow torches if there is a large enough escape point, or b) bombs, and I'm not talking like "da bomb".

Not to mention that most pure alcohol fires are so faintly blue that in daylight are not really visible.
 

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solsticeman: I guess this is getting pretty off topic, but anyhow here goes.

Using natural gas vs. using petroleum for generating hydrogen makes a big difference. Not all fossil fuels are equal, and here doing all the calculations with natural gas as the source makes a crucial difference. When using natural gas, total greenhouse gas emissions used during the conversion are low relative toward the amount released during the operation of ICE's. Even when adding in the efficiency of fuel-cells, a fuel-cell EV using hydrogen extracted from natural gas emits several times less greenhouse gases than an ICE (the exact number varies depending on whether the hydrogen is liquified, etc.) but the savings are at least a factor of three. Calculations done using steam reformation of petroleum do not compare and no one is considering doing that in practice. Again, if you want an unbiased, official study released by the U.S. government, check out http://transtech.anl.gov/v2n2/well-to-wheel.html. They give lots of information concerning well-to-wheel regarding energy, greenhouse gases, etc.

Yes, coal fired power plants out generate natural gas by a factor of 3-1 in the US, but that actually hurts battery powered EV's more than fuel-cell powered EV's suprisingly! If you factor in the fact that the grid is at best 70% efficient itself, battery charged EV's actually have only slightly less greenhouse gas emissions than natural gas sourced fuel-cell EV's! Again that is in the Argonne Labs report. This whole grid inefficiency, and coal power generation combination has become a sobering reality for lots of EV fans. Of course the real answer is to move towards cleaner electricity generation altogether. In the short term, driving natural gas-hybrid ICE's actually is one of the most cost-effective solutions for both the environment and petroleum reduction, but I don't blame the auto industry for swinging for the fences with hydrogen. It will also rely on natural gas in the short term, but has long term pay-offs.

As far as fossil fuels go, coal is indeed in the highest abuncance in the U.S. Natural Gas however, is a big unknown, although the latest reports suggests the U.S. has vast amounts of what used to be called 'unconventional sources' for NG. Most geologists now believe the U.S. has more than 100 years worth of extractable natural gas reserves, even if all transportation became NG based. If there was demand, production of NG will easily meet demand.

I think the environment is something we should consider, but that is somewhat political and I don't think it is a big factor in the end. The real driver for hydrogen (or battery powered EVs for that matter) is petroleum. There are actually plenty of petroleum reservers in the world, especially if you count the recently discovered Canadian tar sands. The crux of the matter is that the U.S. has increasingly smaller share of this oil. 10 years ago we produced over 60% our own oil, now we produce less than 40%, and in 10 years we'll produce less than 10%. This is the one shadow that lingers over economic growth in this country for the next decade, and everyone is starting to realize this. So I think there will be a drive for a new energy source, and in the short term it will likely be natural gas. This matches well with hydrogen powered fuel-cells, and I think that is why all the effort goes there.

Batteries are a nice and clean technology (aside from the fact that they actually generate more toxic chemicals than almost all other industries), but again the problem is the change in lifestyle (or the perception of such a change) they would require. Basically if people aren't willing to drive a minivan over an SUV even while Americans are dying out there in the middle east, they aren't likely to accept a car that they can't take out if they forget to recharge for 4 hours. Don't get me wrong, I myself am a big fan of EVs, but I think realistically you have to consider what people in general consider acceptable, not what you or I do.
 

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Solstice006 said:
Actually, all the NASA research provides a lot of practical results for other fields too. I'd say it's one of the most efficient uses of research money out there.
You can search through some of the so-called "spinoffs" of NASA research at: http://www.sti.nasa.gov/tto/spinselect.html
Oh, I'm a big fan of NASA and the manned space program. Don't get me wrong, I think that putting men on the Moon was one of our greatest achievements and proabably the single most spectacular accomplishment in the last 500 years! I simply made that statement because many of the critics of the Moon shots have pointed out, quite correctly, that we could have learned the same amount about the Moon by sending unmanned probes and robots and saved alot of money and time in the process. So if the goal is to explore the cosmos and the Moon in this case, sending men there was a huge waste of time and money.

However, I don't believe that that was the only goal. We really wanted to learn how to put people in space and get them back again. The spin off technologies from the Mercury and Apollo missions were great side benifits that we enjoy everyday, and the phychological effect was to set generations of dreamers in motion thinking of what is possible. The true benifits of the those Moon shots we have yet to realize IMO. Spin-offs in technology very well could be part of the rewards in the quest for a hydrogen economy. Even if we never do make it to a hydrogen economy, we may learn things in the process that will take us who knows where.

Think back to the year 1904 , and think of what we have now. Damb! Given a hundred years, anything seems possible!
 

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AztekzRpurty said:
There was a History channel deal on the Hindenburg recently, and while hydrogen certainly contributed fuel to the fire, the real reason it spread so quickly was the Silver paint used to dope the fabric exterior was practically solid rocket fuel when it dried. That's some fine German engineering there.
Actualy the German Zepplins were some very impressive examples of engineering (exterior dope aside). They were an example of what happens when you push the technology envelope too far too fast. However, they flew millions of trouble free trans-continental miles long before Lindburg, the Hindenburg and Hitler sealed their fate. They were an extremly elegant form of transportation lost to the ages. There are many of us that would pay a lot of money for a ride in an airship such as the Hindenburg, but not gunna happen.

Actually, the Zepplins kind of make Solsticeman's point as well, some very promising technologies sometimes turn out to be dead ends. The airship seemed so promising that they built the Empire State Building to be an airship moaring mast, but never happened. On the other hand, much of the knowledge learned from building ridgid airships was used in making all-metal airplanes a reality as well as keeping people and engines alive and well at high altitudes.

Oh yeah, hybrid roadster... I guess it could be kind of cool in the near future, but I'll have to be convinced that the complexity will be worth the performance gains. If there are no performance gains, then I don't see much point. Solstice hybrid not likely.
 

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AeroDave said:
...
Think back to the year 1904 , and think of what we have now. Damb! Given a hundred years, anything seems possible!
But back in 1950, it was a given that by 1990, 2000 at the absolute latest, we would be driving to work on the "SkyWay" - the flying car, personal gyrocopters, individual lift packs would be the ONLY way to get around. The traditional asphalt would become obsolete, and four-wheeled cars a thing you'd only see in museums or driven by luddites or collectors.

If anyone had done the infrastructre and mechanichal physics math - it would become absolutely obvious that it was pure fantasy. I have a few (not many) copies of refuting papers, but the flying car was a popular concept/fantasy. Nevermind the impracticality without an alternate power source (at minimum) and super advanced technology in traffic management...
 

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Berkpaul, not sure how you're calculating greenhouse gasses, but there is no way methane steam reformation creates less CO2 (the largest component of greenhouse gas when comparing ICE to H2 production) than a clean-burning and scrubbed ICE.

1KG H2 roughly equals the energy content of a gallon of gasoline.

Steam reformation goes like this:
CH4 + H20 -> CO + 3H2, then
CO + H20 -> CO2 + H2
For every 2 KG of hydrogen produced, there is 44 kg of CO2 produced.

For every gallon of gasoline burned in an ICE, there is 2.4 kg of carbon that gets turned into approximately 8.9 kg of CO2.

Even if you use the government figures for an ICE (14% TTW) and the most efficient H2 FCV (52% TTW), and assuming the ICE vehicle gets around 25 Miles per gallon, the ICE car produces 221 g/km, while the "highly efficient methane reformed hydrogen car" produces 147 g/km. But these TTW are skewed - calculations are based on a very inefficient ICE, but an overefficient H2FCV.

There's no magic to figuring out real efficiency - and skewing the energy usage of vehicles. It takes more MJ to move a sedan around with peak of 200 hp capability, vs a 75 hp vehicle the size and ugly shape of the prius - you really should require the same type of energy usage, say 1 MJ/mile driven or something like that. So there's also an assumption that the vehicle of the future will look like a Cobalt, but have the efficiency of something that looks like the EV1.

Actually, there should be a levelling up of practical performance - compare a small Opel Astra ICE that averages almost 40 miles per gallon to the HydroGen3 FCV's - but the point is people's expectations are not in line with a level playing field.

And if you do that, you'll find the Diesel Astra CI-ICE is almost 23% efficient, and the small displacement Gasoline Astra SI-ICE is about 18.5% efficient. And the HydroGen3? Only 36% efficient. That's TTW.

So then the gasoline ICE at 36 miles per gallon is 153 g/km CO2 emission. The HydroGen3? About 212 g/km for natural gas-sourced hydrogen.

The HydroGen3 goes 0-60 in a pathetic 18 seconds, the HyWire around 16 seconds. The 36 mpg 1.6l Astra? 0-60 in 12.5-13.5 seconds. There's a lot more to get used to performance wise if we are thinking H2-FCV's are the way to go.

BTW - todays hydrogen is about 50% from natural gas, about 30% from oil, about 16% from coal, and only about 4% from electrolysis.
 
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