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The following editorial reflects the opinion of the author and not necessarily that of Progressive Engineer.
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Are Hydrogen Fuel Cells the Answer
for Powering Vehicles?

One writer says no way, while another attempts to dispel the myths he says naysayers bandy about.


Hydrogen Car Faces Harsh Detours

By Brock Yates

We the people now understand the benefits of hydrogen-powered fuel cells after the Congress of the United States has bestowed its benediction on the system via an enormous subsidy. A bill co-sponsored by Sen. Hillary Clinton, D-N.Y., mandates the Department of Energy to develop a plan to produce 100,000 fuel-cell cars by 2010 and 2.5 million by 2020. No doubt this was inspired by the colossal success of California's edict to achieve zero-emissions from 10 percent of its vehicle population by the end of the decade. This idea, you may recall, just hit Sacramento's legislative rocks after sales of electric cars barely edged into double numbers.

These grand mandates from the feds and the states are to be praised, not ridiculed. After all, if they are successful, we can expect harsh laws outlawing cancer, the common cold, automobile crashes, insanity, financial panics, depressions, recessions, and even war. Who is to question the wisdom and power of our government in such heady matters?

But of course, there are potholes even for the divinities in the seats of power. For example, while we shout hosannas for the fuel cell and celebrate the impending doom of the internal combustion engine and its filthy petroleum energy source, bad news looms on the horizon. Contrary to conventional thinking and the constant agitprop issuing from the elite media, fuel cells might not be the perfect solution for the environment. Recall that we have been led to believe the cells only emit a few drops of water. That is true, but a potential assault on the atmosphere comes from the source of the fuel cell power -- hydrogen.

We learn from new research that massive conversion to a hydrogen-powered vehicle network could lead to serious leakage of the volatile gas. In case you missed high school physics, hydrogen is lighter than air. It is also highly explosive (remember the Hindenburg?). The entry of unwanted trillions of cubic feet of hydrogen into the earth's atmosphere could radically alter the climate by the gas oxidizing into water when it reaches the stratosphere. This could cause a dangerous depletion of the already threatened ozone layer.

Presuming we reach Dame Hillary's goal of 2.5 million fuel-cell miracles on the road by 2020, this would radically increase the amount of hydrogen manufactured, stored, and dumped into vehicle tanks on a daily basis. Leakage would inevitably occur somewhere during the cycle -- not to mention the occasional explosion. Safe storage of the gas in vehicles remains an unspoken but serious dilemma for vehicle developers.

Add that little problem to those already present in a hydrogen nirvana such as the massive energy costs in manufacturing the gas (which you don't exactly strain from tap water in your kitchen sink) and safely transporting it through a new network to filling stations. Suddenly the whole scheme begins to sound like another feel-good bamboozle, like the now-defunct electric car.

Brock Yates is editor-at-large for Car and Driver Magazine and a columnist for Tech Central Station



Shattering the Myths of Fuel Cells and Hydrogen

By Amory Lovins

Many diverse authors have criticized hydrogen as a fuel lately. Some call it a smokescreen to hide White House opposition to raising car efficiency using conventional technology or fear that working on hydrogen would divert effort from renewable energy deployment rather than complement it. Most arguments reflect errors meriting a tutorial on basic hydrogen facts.

Myth #1. Making hydrogen uses more energy than it yields, making it impractical.
It would violate the laws of physics to convert any kind of energy into a larger amount of another kind of energy. Converting gasoline from crude oil is generally 75-90% efficient from wellhead to retail pump, and electricity from fossil fuel is only about 30-35% efficient from coal to retail meter. Hydrogen is typically converted at efficiencies of 72-85%.

But hydrogen's greater end-use efficiency can more than offset its conversion loss. From wellhead to car tank, oil is typically 88% efficient, with the lost energy mainly fueling refining and distribution. From car tank to wheels, gasoline is typically 16% efficient. Therefore, the average contemporary vehicle is about 14% efficient well-to-wheels. An advanced fuel-cell car's 70% natural-gas-well-to-hydrogen-in-the-car-tank efficiency, times 60% tank-to-wheels efficiency, yields 42% -- three times higher than the normal gasoline car. The energy lost in making hydrogen is more than made up by its extremely efficient use, saving both fuel and money.

Myth #2. We don't have practical ways to use hydrogen to run cars, so we must use liquid fuels.
Wrong. Turning wheels with electric motors has well known advantages of torque, ruggedness, reliability, simplicity, controllability, quietness, and low cost. With an efficiency of 50-70% from hydrogen to direct-current electricity, fuel cells offer the most efficient, clean, and reliable way to make fuel into electricity. Already, many manufacturers have tens of fuel-cell buses and over 100 fuel-cell cars on the road. A German website reports 156 different kinds of fuel-cell concept cars and 68 demonstration hydrogen filling stations, and Fedex and UPS reportedly plan to introduce fuel-cell trucks by 2008.

Myth #3. Hydrogen is too expensive to compete with gasoline.
Wrong. Using fuel-cell cars 2.2 times as efficient as gasoline cars, onsite miniature reformers, which make hydrogen from another fuel, made in quantities of hundreds with each supporting at least a few hundred fuel-cell vehicles and using natural gas at $5.69 per gigajoule or $6 per million British thermal units could deliver hydrogen into cars at well below $2 per kilogram. That's as cheap per mile as U.S. untaxed wholesale gasoline at $0.90 per U.S. gallon or $0.24 per liter.

Myth #4. Since renewables are currently too costly, hydrogen would have to be made from fossil fuels or nuclear energy.
Hydrogen would indeed be made in the short run, as it is now, mainly from natural gas. The fear of many environmentalists that a hydrogen economy would require the construction of many new nuclear power stations is unfounded. New nuclear plants would deliver electricity at about 23 times the cost of new wind power and 510 times that of new gas-fired cogeneration in industry and buildings, so they won't be built with private capital, with or without a hydrogen transition. Remember that long-term, large-scale choices for making hydrogen are not limited to costly
renewables-or-nuclear-electrolysis versus carbon-releasing natural-gas reforming. Reformers can use a wide range of biomass feedstocks which, if sustainably grown, don't harm the climate.

Myth #5. Hydrogen is too volatile and explosive to use as a fuel.
Wrong. Although all fuels are hazardous, hydrogen's hazards are different from and generally more easily managed than those of hydrocarbon fuels. It's 14.4 times lighter than air, four times more diffusive than natural gas, and 12 times more diffusive than gasoline, so leaking hydrogen rapidly rises away from its source. Also, it needs at least four times the concentration of gasoline fumes to ignite, it burns with a nonluminous flame that can't scorch you at a distance, and its burning emits no choking smoke or fumes, only water.

Myth #6. We lack a safe and affordable way to store hydrogen in cars.
Wrong. Such firms as Quantum (partly owned by GM) and Dynetek now sell filament-wound carbon-fiber tanks lined with an aluminized polyester bladder. Extremely rugged and safe, they have come through unscathed in crashes that flatten steel cars and shred gasoline tanks. The car doesn't drive around with highly pressurized pipes, either, because the hydrogen is throttled to the fuel cell's low pressure before it leaves the tank.

Myth #7. Compressing hydrogen for automotive storage tanks takes too much energy.
Wrong. Filling tanks to a pressure of 345 bar takes electricity equivalent to about 912 percent of the hydrogen's energy content. However, most of that energy can then be recovered aboard the car by reducing the pressure back to what the fuel cell needs (~0.33 bar) through a turbo expander.

Myth #8. We'd need to lace the country with hydrogen production, distribution, and delivery infrastructure before we could sell the first hydrogen car, but that's impractical and far too costly.
Wrong. Extensive analysis by the main analyst for Ford Motor Company's hydrogen program indicates that a hydrogen fueling infrastructure based on miniature natural gas reformers, including sustaining their natural gas supply, will cost about $600 per car less than sustaining the existing gasoline fueling infrastructure, saving about $1 trillion worldwide over the next forty years.

Myth #9. Making hydrogen from natural gas would quickly deplete our gas reserves.
Making enough hydrogen to run an entire U.S. fleet of quintupled-efficiency light vehicles would take only about one-fifth of current U.S. gas production. But gas use wouldn't actually increase by nearly that much, if at all. In fact, a well-designed hydrogen transition may even decrease net U.S. consumption of natural gas by saving more gas in displaced power plants, furnaces, boilers, and refinery hydrogen production than is made into hydrogen.

Amory Lovins is co-founder and CEO of the Rocky Mountain Institute (www.rmi.org) in Snowmass, Colorado, a research organization focusing on energy policy and resource issues. This ran in a newsletter published by Sustainable Business.com (www.sustainablebusiness.com) as a condensed version of Twenty Hydrogen Myths written by Lovins.


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Progressive Engineer
Editor: Tom Gibson
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