Hydrogen Vehicles Coming Sooner Than You Thought?

The Pittsburgh Tribune is high on the limited-production of BMW liquified-hydrogen feuled cars, but there are some big caveats not mentioned.

Read the whole thing, as it's high on denying money to the Islamic Middle East, and notes that, except for fossil fuel exports, the entire Arab world has fewer exports than Finland.

But here's the thing about the cars:

The good news out of Munich is that BMW has come up with something that could do a better job than the CIA in defunding al-Qaida. The BMW Hydrogen 7, available next year in a limited series of a few hundred cars in the United States and other countries, runs on either gasoline or liquefied hydrogen.

"Running in the hydrogen mode, the BMW Hydrogen 7 essentially emits nothing but odorless vapor," reports The Auto Channel. "And unlike fossil fuels and traditional gasoline, hydrogen is available in virtually infinite supply."

A BMW engineer took off his glasses for the press and held them a few inches from the car's exhaust pipe. "See, I can even clean my lenses," he said, wiping the warm steam off with a felt cloth.

The aim, says BMW, is to "create a sustainable future for individual mobility independent of fossil fuels" by way of a technology that "does not in any way mean giving up the dynamics and performance typical of BMW." The Hydrogen 7, with a top speed limited electronically at 143 miles per hour, accelerates from 0-62 mph in 9.5 seconds.

Quicker yet, with a top speed of 185 miles per hour and doing 0-60 mph in 6.0 seconds, is BMW's hydrogen-powered H2R, unveiled two years ago at the Paris Auto Show.

Two days after BMW's Hydrogen 7 announcement, General Motors said its hydrogen fuel cell-powered cars should be on the roads as early as 2011. "This is to re-establish our technological credentials with the American public and the American media," said GM Vice Chairman Bob Lutz, speaking at the Camp Pendleton military base as the company delivered a hydrogen concept car that will be test-driven by Marines.

In July, Ford began production of a hydrogen engine that will be used in the E-450 shuttle bus in Florida. In January, Ford's F-250 Super Chief was introduced at the 2006 Detroit Auto Show, a concept truck that runs on gasoline, E85 ethanol or hydrogen.

Here's the problem with hydrogen as a "fuel source." It is not, as Steven Den Beste frequently reminds, a "fuel source" at all, like petroleum is. Rather, it a manufactured fuel, not an energy "source" but a converted energy form.

Stick a hole in an oil well and you have ready-to-use energy bubbling up. It'll burn as-is; invest a iiltte chemical energy into it and it will burn a lot better. It's got buttloads of potential energy in it already, thanks to millions of years of geological energy-inejection.

Hydrogen, on the other hand, is not ready-to-use as energy. We have trillions of tons of it, but it's not in a usuable form for energy.

My chemistry is creaky, but atoms want to reduce their potential energy. H2 is a high energy state for hydrogen. It wants to reduce its potential energy by bonding with other atoms into lower energy states. To make H2, you have to add all that energy back that was given up when it bonded to carbon or oxygen or whatever.

There are no H2 mines as there are helium mines.

So, to make H2 into a fuel will require burning other fuel in order to create the necessary energy to liberate H from its low-energy bondings and create higher-energy H2. And it's just a rule that you always use more energy in creating a different form of energy.

So H2 is a net energy drain.

However, that doesn't mean the necessary energy needs to come from oil. Nuclear reactors and coal-burning plants -- and we've got plenty of uranium and coal -- can provide the necessary energy for relatively low costs and produce the liquid hydrogen needed to fuel cars.

Still, we don't seem to be in any hurry to build nuke reactors or coal-burning plants.

And I'd be interested to know a comparison of the explosive power of a ruptured tank of liquified hydrogen as compared to a similar tank of gasoline. I'm guessing it's a hell of a lot worse to have a hydrogen tank blow up than a gasoline tank. Fuel burns when it becomes a gas, and gasoline is only somewhat volatile. A ruptured tank of liquified (and I assume highly refrigerated/pressurized) H2 is going to become a gas in like 1.3 microseconds and all of its fiery power will be instantly available for an explosion.

I'm not sure I like the idea of America's cars being replaced by bombs on wheels.

But it is, I suppose, hopeful. You take your optimism where you can get it.

Thanks to OgreGunner.

Hydrogen Bottle In A Bigger Bottle: Maybe the hydrogen tank can be held inside a bigger bottle containing a gas that desperately wants to bond with hydrogen, resulting in a less-exposive or even inert gas, so, theoretically, most escaping H2 would be immediately converted to some less-flamable compound.

You know that wouldn't work all the time, though. And anyone who wanted to make deliberately make their car into a bomb would just empty out the bigger bottle of gas so that only H2 would be flying out of a ruptured tank.

posted by Ace at 04:13 PM

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