Zubrin's costs are probably too low.

Electrolyzers have an efficiency of about 70%, but that is before before expending the energy to compress the resultant hydrogen gas to 10,000 psi (not 5,000 psi), at least if you want a hydrogen fuel cell vehicle with any decent range.

Is 30kW enough capacity?

Seems undersized for a car.

I'm skeptical of rapid adoption of charging stations - how do you persuade OEMs to use fast-charge (much more expensive) batteries?

AFAIK, the fastest I'll be able to charge a Volt will be via whatever my dryer circuit can deliver (220V, 30A?)

Sticking a 100-mile battery pack (even in an 18-wheeler) with a fossil-fuel powered genset (gasoline/E85, diesel or natural gas) is still cheaper (for both capital & operating costs) than using a fuel cell.

Why bother with fuel cells at all given the above?

Hydrogen from electrolysis is too expensive.

Hydrogen for vehicle fuel cells will continue to come from natural gas.

Sorry, but the cost (both capital and operating) rules out PEM fuel cells.

At best they are only about twice as efficient as an ICE, currently cost 100x as much as an ICE, and also use a much more expensive (and hard to handle) fuel.

If some bright engineers could adapt for vehicle use a fuel cell that can directly burn a more complex hydrocarbon (natural gas/LPG, or ideally a liquid fuel) then fuel cells would have a better chance in mass-market vehicle applications.

But again, fossil-fueled range extenders are so cheap to make and operate I don't see that happening by 2015.

Mollar skycar!

While they are fun toys for engineers, PEM fuel cells will never be cheap enough to use in a mass-market vehicle.

In 2015 the range extender (if present) on an electric vehicle will be an ICE-based genset running on fossil fuel (gasoline/E85, diesel, or natural gas/LPG)

They are both cheap and able to use existing fuel infrastructures.

If you want a range extender for your electric vehicle it will always be cheaper to use a genset running on fossil fuel (natural gas would be cleanest)

Rather than spending 6 figures for a fuel cell range extender.

Even "by 2015" the only range extenders on production electric vehicles will be those fueled by gasoline/E85, diesel, and natural gas.

It's technically possible, but inefficient to make hydrogen for vehicle fuel cells (themselved not very efficient either)

Costs are what kills vehicle fuel cells.

Both the cost of the fuel cell stack and other components (very expensive carbon-fiber storage tanks required for any decent range), the cost of building a refueling infrastructure, AND the operating costs are higher than alternatives.

If one needs a range extender for your electric vehicle, then simply choose a fossil-fueled genset (gasoline or E85) - run it on natural gas if you want it cleaner.

That option is a tiny fraction of the cost (both capital and operating) of any fuel cell range extender.