The Wall Street Journal
Advocates of a hydrogen-powered future -- when cars run on nonpolluting
fuel cells -- liken their vision to shooting for the moon. Now some environmentalists
and auto makers are talking up a less ambitious, and less clean, half-step:
cars that burn hydrogen in fairly conventional internal-combustion engines.
Fuel cells are widely seen as the ultimate clean-car technology because
they convert hydrogen into electricity to power electric motors, and emit
nothing but clean water. But realizing that goal is a long way off. This
month, the National Academy of Sciences issued a report calling a Bush
administration plan to spend $1.7 billion on hydrogen research over five
years "unrealistically aggressive," saying a full transformation by the
U.S. to hydrogen from gasoline could take until 2050.
Concerns over that long timetable have split the auto industry. Some
car makers, prompted in part by California clean-air
regulators, want to convert some of today's engines so they can burn
hydrogen instead of gasoline. Germany's Bayerische
Motoren Werke AG says it plans within two or three years to roll out
several hundred of its top-of-the-line 7-series sedans
with modified engines that burn both hydrogen and gasoline. Ford Motor
Co. is considering building a demonstration fleet
of cars that use hydrogen in internal-combustion engines. These car
makers say this half-step would get hydrogen-powered vehicles on the road
sooner and ease the transition to the cleaner fuel, in part by prompting
the oil
industry to sell hydrogen at gas stations.
Others, principally General Motors Corp., say the industry should wait
until fuel cells are ready. Armed with a new study
by a federal laboratory, GM argues that burning hydrogen in converted
auto engines actually could be worse for the environment than today's vehicles,
in part due to the pollution caused by making the hydrogen fuel.
The soon-to-be-released study by Argonne National Laboratory -- bankrolled
by GM and some major oil companies -- finds that cracking hydrogen molecules
from natural gas, and then compressing the gaseous hydrogen so it can fit
into a tank on a vehicle, actually emits larger quantities
of two problematic air pollutants than refining gasoline does: soot
particles, which have been linked to respiratory disease, and nitrogen
oxide, which helps form smog.
Then there's the pollution created when the hydrogen is burned in an
internal-combustion engine. Based on GM's projections of emission levels
from a full-size pickup, the study concludes
the truck would cough out about the same amount of nitrogen oxide and
soot whether it's burning hydrogen or gasoline.
The upshot: At least until hydrogen can be produced cleanly from renewable
energy sources such as the sun or wind -- a process that today is hugely
expensive -- hydrogen-burning cars will be a dirtier option than gasoline-burning
cars.
Michael Wang, an Argonne scientist who worked on the study, says he
did a double take when he saw the results. "I had to
go back, step by step, and check my sources," he says.
GM says it hopes to be selling "commercially viable" fuel-cell vehicles
by 2010, that it and isn't working on hydrogen-burning
internal-combustion vehicles in the meantime.
Many environmentalists have criticized talk of hydrogen-powered cars
as a smokescreen by industry to avoid building vehicles that go farther
on a gallon of gasoline. Some cite the Argonne study as fresh evidence
for such concern. "The Argonne scientists are warning us as plainly as
they can not to confuse real solutions with wishful thinking," says Jay
Gourley of the Public Education Center, a Washington-based environmental
advocacy group.
The staunchest proponents of burning hydrogen in modified engines are
in California, the environmental bellwether.
Regulators there have amended a state rule requiring the auto industry
to build some "zero-emission" vehicles to give the
industry partial credit for cars that burn hydrogen in internal-combustion
engines. Gov. Arnold Schwarzenegger has announced plans to build a network
of hydrogen-fueling stations -- and to convert one of his own gas-guzzling
Hummers to hydrogen.
Modifying a car to burn hydrogen involves several steps. One is to add
a special fuel tank and fuel hose that can withstand
the high pressure at which hydrogen must be stored. Another is to redesign
the component that mixes fuel and air and sends it into the engine's cylinders.
Officials at BMW and Ford, as well as at the California Air Resources
Board, the state's clean-air cop, downplay the Argonne study. They concede
that burning hydrogen in an
internal-combustion engine is far less efficient at producing power
than running the hydrogen through a fuel cell. But they
say the auto industry could make hydrogen-burning cars a lot cleaner
than GM assumes. And they suggest the conclusions of the GM-funded study
are predictable given GM's distaste for any hydrogen technology short of
the fuel cell.
Jerry Martin, a spokesman for the California air board, says vehicles
with internal-combustion engines that burn hydrogen won't get any credit
under the state's zero-emission-vehicle rule unless they achieve extremely
low emissions -- levels below what the Argonne study assumed was feasible
for GM's full-size pickup.
Christoph Huss, BMW's senior vice president for science and traffic
policy, says his company thinks hitting the California clear-air target
is feasible with its hydrogen-fueled 7-series sedans. BMW, in fact, regards
internal-combustion engines as the most viable format for hydrogen cars
"for the next 20 years," he says. "Maybe BMW is the single company that
has done these R&D (research and development) programs," he adds.
At Ford, Gerhard Schmidt, vice president for research and advanced engineering,
expresses similar doubts about the
Argonne findings. "These studies have a lot of assumptions -- especially
when people are not running hydrogen internal-combustion engines like we're
doing," he says.
As for the pollution that comes from producing hydrogen fuel from natural
gas, even critics of the Argonne study
acknowledge it's a problem. But they say that, to build an economic
case for producing truly clean hydrogen from
renewable sources, it's a price worth paying.
