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Discussion Starter #1
An interesting experiment is taking place in Europe right now : GM is attempting a Fuel Cell Marathon with his HydroGen3, from Norway to Portugal. You can read the daily reports on the AutoBild pages (one page in German is followed by one page in English).

GM engineers presented the absence of backup battery in their new vehicle as an improvement compared to the previous version. Now they're probably scratching their heads when considering the real-world data.

Here they are : the HydroGen3 must stop every 150 km (93 miles) at the latest to fill up the tank with about 75 liters of liquid hydrogen, as you can read here. The report says they are weighing "less than five kilos", actually one liter of liquid hydrogen makes 70.8 g so 75 liters should be 5.3 kg. Let's take 5 kg : that is 3.3 kg for 100 km or 33 g per km (compared to the claimed 6.4 g/km for science-fiction projects like the still-non-existing "Revolution" car, see page 17 of this document), or 54 g per mile.

Given the energy content of about 33 kWh / kg, the HydroGen3 therefore uses 165 kWh of hydrogen energy for 150 km, or will go 0.91 km (0.57 mile) per hydrogen kWh. This is already much worse than clett's figure of 0.8 mile per primary energy kWh :
1 kilowatt hour used to make hydrogen by electrolysis, then compressed, transported and burned in a fuel cell car provides a range of about 0.8 miles.
But remember, it takes much more energy than the energy content of hydrogen to make this clean fuel... so you can almost divide again by 2, roughly.

Some opponents to hydrogen economy base their calculations on a 50 miles per hydrogen kg figure to prove how inefficient fuel cell vehicles are (see here, top of page 9). GM tells them right now they should take less than 20 miles if they were using HydroGen3... :?

Well, that's not a reason to bash fuel cell cars forever... just a hint to think GM is trying to make them consume as much hydrogen as possible. Probably to pep up hydrogen economy and pay off infrastructure costs ? :wink:
 

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Hi Frenchie,

Wow that GM fuel cell car really sucks! Let’s have a little run down against the “competition” and see how it stands....

GM Hydrogen3 - 18.9 miles per kilogram.
Ford’s Focus FCV - 45 miles per kilogram
Honda FCX - 50 miles per kilogram
Toyota FCHV - 64 miles per kilogram

If we used hydrogen made from electricity (it takes about 60kWh to make and compress a kilogram of hydrogen), things look even worse!

GM Hydrogen3 - 0.32 miles per kWh.
Ford’s Focus FCV - 0.75 miles per kWh.
Honda FCX - 0.83 miles per kWh.
Toyota FCHV - 1.07 miles per kWh.

That means that from the same amount of primary energy, GM’s own EV1 of TEN years ago was able to go 15 times further per kWh than their current so-called technical tour-de-force! Is that their new definition of progress? I think you might be right in your final assessment Frenchie! ;)
 

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Just a quick question. When ever anyone talkes about the downsides of Hydrogen, they talk about the energy spent to produce it (separate it from water or whatever). However, when ever anyone talks about gasoline, no one ever mentions how much enegry is used to refine it from crude oil into gas. Is there something I am missing?
 

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See the May 2004 issue of Scientific American for a discussion of these very issues.

The "well-to-wheels" efficiency of gasoline is about 80%, whereas the "well-to-wheels" efficiency of separating water to get hydrogen, using electricity from the grid, is only 20%. Steam reforming of natural gas to get hydrogen is much more efficient at 60%, but we're on the down slope of our natural gas supply.

Anyway, read the article, it's a pretty good review of where we are now.
 

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Discussion Starter #5
GM fool cell car, continued...

Reading the daily AutoBild reports I was referring to, I'm disappointed today because the last reported stage (Salzburg :arrow: Torino) is only available in German so far. OK, let's try to remember my (very poor) German, after all es ist eine gute �ung, oder ?
On page 2 I'm extremely surprised to read this sentence :
Wir verbrauchen ganz genau 1 kg Wasserstoff pro 100 km Fahrt
which translates approximately in : "We consume exactly 1 kg hydrogen for 100 km of travel"
:shock: What ? Are they getting now fuel consumption comparable to that of Toyota's FCHV (the most efficient one) after such a pitiful efficiency during previous days ? Remember : about 30 km per hydrogen kilogram... has the engineer team finally corrected a bug in the software ?
Then I read more carefully, and understand that as always, context is everything. Let's quote a little more text :
Sterzing, Brixen, Franzensfeste. Wir verbrauchen ganz genau 1 kg Wasserstoff pro 100 km Fahrt, nutzen bergab den Schwung (Motorbremse gibt es in diesem Auto keine).
In other words, they don't consume that much because they're driving downhill after passing the Brenner pass... below you can see the route between Sterzing/Vipiteno and Brixen/Bressanone that I've emphasized using ViaMichelin.
And, yes, Franzenfeste is between Sterzing and Brixen, Mr. journalist. :wink:
 

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So all we need to do is make all roads go downhill, and we've solved our energy problem.

Maybe we could get M.C. Escher to design our road system.
 
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