Hydrogen promises and pitfalls

With an energy symposium planned for Oct. 18-19 in Bozeman, where Gov. Brian Schweitzer will meet with other governors and notables to discuss energy solutions, it's worth making a few points about an important subject.

Concerns about global warming and peak oil have fueled a growing political-industrial and political-environmental complex that is lobbying hard for creation of a hydrogen-based economy, but if there's anything worse than mixing politics with religion, it's mixing politics and science.

In last year's gubernatorial campaign, Schweitzer touted Montana's vast coal deposits and called for the state to take the lead in jump-starting a hydrogen economy. In California, Gov. Arnold Schwarzenegger called for creation of "hydrogen highways" with a statewide network of 200 hydrogen filling-stations.

Automobile manufacturers and energy companies have jumped on the idea — we don't get rid of cars, we just burn a different fuel. Sprawl and traffic fatalities are not an issue here. (It's worth noting that General Motors coined the expression "hydrogen economy.")

Energy companies can benefit from the transition to the new economy — according to the Bush administration's National Hydrogen Energy Roadmap, about 90 percent of hydrogen production would come from fossil fuels. Renewable energy sources, such as wind and solar, would play a part sometime in the distant future.

On the other side of the political spectrum, proponents of the new economy have starry-eyed visions of a "forever fuel" that never pollutes and will wean Americans from the stranglehold of greedy corporations and the carnage of foreign wars.

Americans easily gravitate toward high-tech solutions — mag-lev trains, smart highways — without the reasoned approach they might take toward, say, shopping for groceries or considering a dangerous medical procedure. They're exciting ideas that hold out the promise for a beautiful future. But the hydrogen economy has its pitfalls, and they are well worth considering, to wit:

? Energy cannot be created nor destroyed. There is no such thing as a free lunch — or perpetual-motion machines. Hydrogen may burn cleanly, but it must be manufactured, and that takes energy.

To produce hydrogen by electrolysis using electricity generated by coal-fired plants would take six energy units of coal to produce one energy unit of hydrogen. The ratio is much better when coal is used to produce hydrogen by steam reforming — two units of coal produce one unit of hydrogen. In both cases, global warming gases or hazardous pollutants are also emitted.

Wind could be used to produce hydrogen through electrolysis, but it would take more than 300,000 of the largest and most advanced wind turbines in the world to produce enough hydrogen for America's transportation needs. And the kind of wind needed is not located near America's population centers.

One way to measure energy efficiency is called "wells to wheels" — which includes losses from exploration, production, transportation, refining, distribution and consumption for fossil fuels or any other energy source. For coal to hydrogen by electrolysis, losses total about 92 percent; for natural gas to hydrogen by steam reforming, it's about 78 percent; for gasoline internal-combustion engines, it's about 88 percent; and for diesel internal-combustion engines, it's about 83 percent.

Some experts say using natural gas to produce electricity would be a better use than making hydrogen — natural gas is twice as efficient as coal in terms of energy units, and it produces a quarter as much global-warming carbon dioxide as coal. But it's worth noting that natural gas prices are extremely unpredictable and volatile.

? The hydrogen economy's infrastructure would be expensive, inefficient and dangerous. And it would replace a working infrastructure that's been in place in America for more than a century — electrical transmission.

For one, hydrogen is a difficult molecule to store and transport. It boils at minus 423 degrees Fahrenheit, and it doesn't compress easily. Natural gas boils at minus 259 degrees and is easily compressed. Compressing and liquefying hydrogen can account for 20 to 40 percent of the energy content of hydrogen production.

A tank of hydrogen at 11,613 pounds per square inch would have one-third the energy content of natural gas at the same volume and pressure. One tanker truck of gasoline would contain the same energy content as 15 tanker trucks of hydrogen.

All that pressure is only half the story — the hydrogen molecule is the smallest known to man, consisting of two protons and two electrons. The result is leaks that are both energy-inefficient and dangerous.

Not only is hydrogen gas colorless and odorless, its flames are colorless. A leaking hydrogen tank could be burning and you wouldn't know it.

Furthermore, hydrogen's flammable range is 2 to 75 percent, compared with 5 to 15 percent for natural gas, which increases the chances for ignition. Anyone familiar with the May 3, 1937, Hindenburg zeppelin disaster knows the result.

? Assuming the mechanical difficulties of hydrogen transportation and storage can be solved, other costs must be addressed. There are about 60 hydrogen fuel-cell vehicles on the road in California, and each costs about $1 million. Even if mass production brought vehicle costs down, fuel-cell power production runs about $4 per watt compared to 5 cents per watt for gasoline engines. A vast improvement in cost is needed to propel America into this new paradigm.

The Bush administration coughed up about $1.7 billion for its Hydrogen Fuel Initiative several years ago, but it must deal with 200 million motor vehicles burning 20 million barrels of oil per day.

Peak oil is no joke. Nor is global warming. But a hydrogen-based economy is not the answer — it merely compounds existing problems and doesn't address the fact that there are too many motor vehicles on the road. Addressing that issue is more a social-engineering problem than a mechanical-engineering one.