How to Promote the Hydrogen Economy Hoax

One thing I'd love to see, and soon, is an end to the abuse of the term "MPG" on EV forums. "MPG" means "Miles Per Gallon", as in "the number of miles driven per gallon of fuel, in a vehicle is powered by gasoline/diesel". It doesn't mean "miles driven when powered by some form of energy which can be vaguely but not accurately equated to the amount of energy in a gallon of gasoline". Nor does it mean, as it's misused on Volt forums, "miles driven on a gallon of gasoline plus a variable and unreported number of kWh of electricity".

 

What's intellectually lazy is criticizing an argument without even trying to refute it.

I think the "If you believe fool cell cars can someday become practical, then why not steam-powered cars?" is an excellent argument. The ball is in your court to demonstrate otherwise.

The problem with arguing against it, as I suspect you've already realized, is that any argument against using steam powered cars would be equally valid against fool cell cars. And I suspect that's why you haven't even tried to refute it.
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There seems to be a consensus among the Usual Suspects posting to comment threads at the InsideEVs news site, that the term "MPGe" includes charging losses. That is, that the kWh are measured from the wall, not from what's stored onboard the car in the battery pack. Note this is directly contrary to what the Wikipedia article says about MPGe. Of course Wikipedia isn't always right, any more than any encyclopedia is always right, but when they ask you what their source is, they point to one single reference in a FAQ at a government energy agency site.

I don't know who is right, but if there is a discrepancy in the figures, that might account for it.

Given what the Wiki article says, it may be that the term "MPGe" is used to mean different things by different people or different agencies. Perhaps some mean it to be -- as the Wiki article claims -- only a measure of how efficient the energy stored onboard is, and thus about as close to the MPG metric as we can get with EVs. Perhaps others, as the Usual Suspects posting to the InsideEVs news article comments insist, mean it to be a measure of electricity drawn from the wall, which includes charger losses.

So far as I'm concerned, it's not a settled point, altho the Usual Suspects over on the news site disagree.

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My opinion:

I have a personal distaste for the term "MPGe", not only because it's confusing -- and we're having this discussion precisely because it's confusing, in that we're not really sure exactly what's being measured -- but also because it seems to be a crutch aimed at the general public, who have been educated in the ways of gasmobiles and what "MPG" means, but not in the ways of EVs and what such things as "watts" and "kilowatt-hours" are. Also, sadly, the general public has not been educated in school about the difference between power and energy, which you would think would be part of basic introductory science courses in elementary school, or at worst in middle school, but it's not.

As I've said elsewhere, it's as if back in the days of the Model T, the government had instituted a measurement of BHDe (Bales of Hay per Day equivalent), instead of MPG, to ease the transition from those familiar with the horse-and-buggy but not motorcars. If we had introduced that crutch back circa 1908, would we still be using it today? Unfortunately, I kinda think we would.

As they say: "Begin as you mean to go on." If the idea is to educate people in the ways of EVs rather than gasmobiles, then we shouldn't be using the crutch of "MPGe", which seems to suggest that EVs are just a kind of gasmobile which uses a special fuel.

Again, all this is just my opinion, and obviously many disagree.

 

Indeed. At some point, at the steepest rise on the "S-cure" of adoption, installation of L2 charge points and DCFC charge points are going to have to be at the rate of millions per year.
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The ball is in your court to show where or how it's nonsense.

Once again: If you believe FCEVs powered by compressed hydrogen fuel can someday become practical, then why not steam-powered cars?
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From my viewpoint it's entirely valid, and you are the one side-stepping the issue by labeling it a "strawman argument".

No, you're trying to paper over the actual issue. The reasons steam powered cars can't compete with gasmobiles are exactly the same reasons that hydrogen-powered cars can't compete. The impracticality and the lack of efficiency are the same issues.

Furthermore, fuel cell cars have been in development about as long as modern EVs have. The reason why EV tech has progressed and FCEV tech has not, isn't because of lack of time and resources. It's because there are real-world constraints, due to physics, thermodynamics, and basic economics, that make it impossible for compressed hydrogen to be a practical fuel for wheeled vehicles. The very same constraints which have cause auto makers to abandon steam engine tech in favor of ICEVs and (now) plug-in EVs.

Feed The Trees, perhaps if you knew more about how much time and effort has been put into developing FCEVs, then you'd realize that the analogy with steam powered cars is a pretty exact one; much closer than analogies usually are.
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Steam engines, like all heat engines, are limited in efficiency by the amount of temperature difference between the hottest and coldest parts of the engine. If using silicon as the operating fluid, rather than water, will allow a higher operating temperature for the hottest parts of the engine, then that would at least potentially allow a higher energy efficiency.

But you're still going to be limited by the fact that external combustion engines (like steam engines) are inherently less efficient than internal combustion engines, because there is inevitably some loss of heat between the firebox (heat supply) and the pistons/turbine.

 

Doesn't seem to be much point in trying to claim you could make a steam engine powered automobile that's as energy efficient as a FCEV. A hydrogen-powered FCEV isn't a heat engine. Admittedly the Carnot efficiency limit does still apply, but a fuel cell has a better theoretical efficiency than any heat engine, even an ICEngine, which in turn has a better theoretical efficiency than the maximum theoretical efficiency of any steam engine. Well, hopefully most alert readers will observe that last statement of mine contains some glittering generalities. But it should be true that any well-engineered ICEngine of the size appropriate for powering a passenger vehicle should be more energy efficient than any well-engineered steam engine of the size appropriate for powering a passenger vehicle.

Obviously steam engines in some cases -- such as the steam turbines in natural-gas-fired power plants -- can be more energy efficient than mass produced automobile ICEngines. Energy efficiency favors larger engines, especially when it comes to heat engines. That applies to both ICEngines and steam engines.
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