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Guenter Schmied / BMW via Reuters
German luxury carmaker BMW unveiled the world's fastest hydrogen-powered
car, dubbed the H2R, at the Paris auto show this week.
Updated: 10:13 a.m. ET Sept. 24, 2004 PARIS - German luxury carmaker BMW
unveiled the world’s fastest hydrogen-powered car at the Paris auto show.
Dubbed the H2R, it's capable of exceeding 185 miles per hour.
“Our drive towards the future is called hydrogen,” but in a way that gives
a green twist to existing engine technology, BMW management board member
Burkhard Goeschel said before the tarp slowly slipped off the sleek,
zero-pollution car.
Goeschel, responsible for technology and development at BMW, said the
streamlined rocket car sprints from 0 to 60 mph in about six seconds and
reached a top speed of 188 mph on BMW’s test track at Miramas, France.
“It’s called the H2R -- ’R’ as in record,” Goeschel said.
6-liter, 12-cylinder engine
Unlike most hydrogen-powered vehicles, the H2R doesn’t operate on fuel
cells but rather uses a modified 6-liter, 12-cylinder combustion engine
for its propulsion. Like fuel cells, the H2R's engine essentially emits
nothing but water.
An advantage of the higher combustion pressure of the hydrogen-air mixture
is its higher degree of efficiency, BMW added.
The company cautioned, however, that while hydrogen itself doesn't
pollute, most hydrogen is still obtained either from fossil fuels such as
natural gas or by applying grid electricity to split water. Either way
releases hydrocarbons.
Solar or wind power can be used to split water, but that process is even
more expensive than via fossil fuel.
While BMW is developing fuel-cell driven cars as well, it says it is
concentrating on the combustion engine because the sum total of its
features and characteristics offers the largest number of advantages and
benefits all in one.
GM, Mercedes execs weigh in
Most other carmakers are focused on fuel cells, but remain open to other
approaches.
“Our bet is that the way to take the automobile out of the environmental
equation is the hydrogen economy and hydrogen-based fuel cells,” said
Fritz Henderson, the head of General Motors’ European arm. “We are
spending a lot of time, money and effort to get there, but you can’t focus
on only one (technology). You have to keep your feet in various different
camps.”
Juergen Hubbert, head of DaimlerChrysler’s Mercedes division, had a stock
answer when asked when fuel-cell cars would become a reality.
“This question comes up every year and ... I always have to say it will
take 10 years,” he said, noting Daimler was making good progress with fuel
cells but still faced bumps in the road.
“We have reduced volume (of fuel cells). We have reduced weight. What we
couldn’t reduce so far is costs. Costs are still by far too high,” he
said.
He cited a chicken-and-egg situation in which volumes had to go up to
bring prices down, while high prices were keeping a lid on the size of the
potential market. Fuel cells add thousands of dollars to the price of a
standard car.
Nevertheless, fuel-cell cars are on the way, he said. “I think we will
have a significant market share, like you see actually with the hybrids,
between 2010 and 2012,” he added. |
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Questions and Answers:
Source: National Renewable Energy Laboratory, U.S.
Department of Energy
What makes hydrogen an energy tool?
The most common element in the universe, hydrogen has the highest energy
content per unit weight of any known fuel. Yet it never occurs by itself
in nature - it always combines with other elements such as oxygen (for
water) and carbon (for fossil fuels).
Once separated, hydrogen is the ultimate clean energy carrier. It can be
non-polluting, is as safe as gasoline and can be produced anywhere.
NASA's space shuttles use hydrogen-powered fuel cells to operate
electrical systems and the key emission, water, is consumed by the crew.
How is Hydrogen produced?
It can be extracted from any substance with hydrogen: water, fossil fuels
and even some organic matter.
Almost all of the 40 million tons of hydrogen used worldwide today comes
from natural gas though a process called reforming. Natural gas is made to
react with steam, producing hydrogen and carbon dioxide. The hydrogen is
then used to make ammonia for fertilizer, in refineries to make
reformulated gasoline, and in the chemical, food and metals industries.
This is the cheapest way to make hydrogen today and is likely the way we
will make
hydrogen for fuel cell vehicles in the near future.
Hydrogen also can be made from coal in a similar process where the coal is
reacted with steam. Either way, though, the process releases carbon
dioxide, a gas tied to global warming.
Carbon-free methods involve splitting water into its component parts of
hydrogen (H2) and oxygen (O). Electrolysis uses an electric current to
separate water into hydrogen and oxygen. The electric current has to
itself be produced, and the easiest but least efficient way is via some
fossil fuel. The holy grail of hydrogen is to use a renewable source like
solar, wind, hydro, geothermal or biomass power to create the current,
making the process pollution free and sustainable.
Heat or electricity from a nuclear power plant could also be used to split
water, but that path still faces nuclear waste and security issues. Future
possibilities include using the power of ocean waves to generate
electricity and microorganisms that could be adapted to produce hydrogen.
How much water would we need if we got hydrogen that way?
Actually, not that much compared to what we already use. If we converted
the current U.S. light-duty fleet (some 230 million vehicles) to fuel cell
vehicles we would need about 310 billion gallons of water per year.
Domestic water use is about 4.8 trillion gallons per year, and 70 trillion
gallons a year are used for thermoelectric power generation. Interestingly
enough, the refinery industry uses about 300 billion gallons of water a
year to produce gasoline.
How do fuel cells fit in the hydrogen picture?
Fuel cells are often compared to batteries. Both convert the energy
produced by a chemical reaction into usable electric power. However, the
fuel cell will produce electricity as long as fuel (hydrogen) is supplied,
never losing its charge.
And while hydrogen could be used to run an internal combustion engine,
fuel cells are inherently 2-3 times more efficient – in the case of a car;
that means they can get 2-3 times the mileage.
Like batteries, fuel cells’ performance declines over time and they have
to be replaced. The goals for fuel cells are 5,000 hours of operation for
transportation (representing about 150,000 miles) and 40,000 hours (about
5 years) for stationary applications. Some fuel cell technologies can
match the stationary needs for 40,000 hours, but we are only about a third
of the way there for vehicles, a much more demanding application.
What's holding up wide scale production?
Cost is the biggest impediment. Electricity is required by many hydrogen
production methods, which so far makes hydrogen more expensive than the
fuels it would replace. With cars, gasoline is still easier to store than
hydrogen, which needs to be compressed or kept at very cold temperatures.
In addition, an infrastructure would have to be built, and paid for, in
order to produce, transport and store large quantities of hydrogen.
Wouldn't we run out of oxygen and see excess water vapor?
No. Producing hydrogen produces and consumes oxygen in the same ratio.
As for water vapor, burning gasoline already does that, though fuel cell
vehicles produce about twice as much per mile. This is still a relatively
small amount compared to what is already in the atmosphere naturally, and
a tiny amount compared to what is being added by global warming.
How much does hydrogen cost?
Most of the hydrogen produced today is consumed on site, such as at an oil
refinery, where it costs 32 cents a pound. When hydrogen is sold on the
market, the cost of liquefying and transporting it to the user increases
the price to $1-1.40 a pound. A pound of hydrogen has a bit less energy
than a half gallon of gasoline.
Is hydrogen safe and didn't it cause the Hindenburg disaster?
In general, hydrogen is neither more nor less inherently hazardous than
gasoline, propane, or methane.
As for the Hindenburg, a recent study found the paint used on the blimp's
skin was to blame since it contained the same component as rocket fuel. An
electrical discharge ignited the skin. While the hydrogen gas used to
float the blimp did ignite, it burned upward and away from the people on
board and actually provided a slow, safe descent for those who stayed on
board.
Don't you lose a lot of energy when you make hydrogen?
Indeed, all energy systems lose energy (an average coal plant loses 70
percent of the energy in the coal), so we need to think very carefully
about where we are going to get this energy. The sun could be the answer.
Think about it for a minute and you’ll realize that we are all solar
powered - the food we eat for our energy ultimately comes from plants
converting solar energy to carbohydrates with an efficiency of about 1
percent. Of course, by the time the food hits the table the efficiency is
much lower, probably around 0.1 percent. Current commercial solar cells
can convert solar energy with an efficiency of more than 15 percent.
If we take that energy and make hydrogen and then use that hydrogen in a
fuel cell vehicle, the overall efficiency of sunlight to vehicle power is
about 4 percent. So using hydrogen from sunlight, we can drive ourselves
around with an efficiency of at least 40 times greater than we can walk.
Can't I put water in my tank - It's got hydrogen in it?
Water is not an energy carrier like hydrogen and gasoline. You have to
take the water and add energy to split it into hydrogen and oxygen. The
hydrogen then becomes a fuel, because it now carries that energy that you
added. When that hydrogen reacts with the oxygen in the air it releases
that stored energy and you can use that to move the car. So if you wanted
to use water as a “fuel” you would have to have two power plants in your
car, one to make the hydrogen and one to run your vehicle. Better to make
the hydrogen separately and just fill your car with energy.
How about putting solar cells on the roof of my car?
Our cars take a lot of energy and while there is a lot of energy in
sunlight, the rooftop of your car does not have enough area. For an
average car you’d need something like the size of a football field – not
very practical.
How much is hydrogen from renewables going to cost?
With today’s technologies using electricity from wind, hydrogen would cost
between 3 and 5 times that of gasoline. In Europe, where gasoline is
already 3 to 5 times higher than the U.S. prices, hydrogen represents a
cost-competitive fuel and with the higher efficiency of fuel cell
vehicles, a strong possibility as an alternative fuel.
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