快猫短视频

THEY鈥橰E calling it the 鈥淏ahrain of the North鈥�. These are exciting times in
Iceland, the birthplace of the hydrogen economy. Thorsteinn Sigfusson, professor
of physics at the University of Iceland in Reykjavik and chairman of Iceland New
Energy, says that within 20 years his country can become the first in the world
to run on hydrogen without recourse to fossil fuels. To start with, hydrogen
will run its fleets of buses, trucks, cars and trawlers, and later it will
provide electricity and heat its buildings through the long winters. Iceland
could be the first of the 21st-century successors to the OPEC sheikhdoms. Call
them HYPEC鈥攖he organisation of Hydrogen Producing Countries.

It鈥檚 early days yet, Sigfusson admits. The first three hydrogen-fuelled buses
won鈥檛 hit the streets of Reykjavik until 2002. That鈥檚 several years after
Vancouver and Chicago introduced theirs. But Iceland鈥檚 buses are the start of
something much bigger. Unlike most hydrogen-powered buses, which fill up with
hydrogen derived from old fuels such as oil, Reykjavik鈥檚 buses will run on
hydrogen made by splitting water, using hydroelectricity generated from
Iceland鈥檚 raging rivers. The umbilical cord to fossil fuels will be cut.

Since Iceland has a population of only 276,000, and you can鈥檛 drive there
from anywhere else, it is an ideal place to test out a future world where cars
are no longer environmental pariahs, where urban smogs and greenhouse gases are
banished. A world, in short, that has kicked the carbon habit.

Ask anyone with a stake in the energy economy if the revolution is really
necessary and they will say yes. There are compelling reasons for change.
Emissions of carbon dioxide from internal combustion engines are stoking the
greenhouse effect. Burning oil fills our cities with smogs that kill hundreds of
thousands every year. Technological improvements to cut emissions from
conventional cars cannot keep pace with the rising tide of vehicles. There will
probably be a billion on the world鈥檚 roads by 2020鈥攐ne for every seven
people.

Meanwhile, the oil economy is starting to give us a bumpy ride. Nations the
world over remain shackled to OPEC鈥攁 risky position to be in, as the price
hikes of the past six months have shown. It doesn鈥檛 take much to rock a
government and threaten global recession. And one day the oil will run out. Oil
geologist Colin Campbell was quoted in 快猫短视频 last year as
saying that 鈥渢he world鈥檚 oil companies are now finding only one barrel of oil
for every four that we consume鈥�
(10 July 1999, p 49).

Even big oil companies now concede that we cannot carry on burning oil as we
have in the past. 鈥淚f the motor car is to stay with us, we need to explore
radical new ways to fuel it,鈥� says Paul Histon, fuels technology manager at BP
Amoco鈥檚 oil technology centre in Sunbury-on-Thames near London. 鈥淚f we are truly
to get big CO₂ reductions, hydrogen is the best long-term choice.鈥�

Why hydrogen? Well, it鈥檚 ubiquitous, inexhaustible and clean. You can drive
across the US on hydrogen without adding to the atmosphere anything more noxious
than a bathtub-full of water. Back in 1874, Jules Verne argued in The
Mysterious Island that when fossil fuels run out, hydrogen 鈥渨ill furnish an
inexhaustible source of heat and light鈥�. Hydrogen鈥檚 time seems to have come.

Safety fears

But is it safe? Some industrialists argue that storing hydrogen on filling
station forecourts or in vehicle tanks is too dangerous. The image of the 1937
Hindenburg airship disaster still looms large. This is curious. The hydrogen
filling the airship did not explode, and the 35 dead were either killed by
burning diesel or jumped to their deaths. In 1997, a retired NASA scientist
found that the real culprit was the flammable fabric of the airship鈥檚 outer
skin, not the hydrogen.

And let鈥檚 not forget that cars are already carrying round tanks of
dangerously explosive liquid, so it鈥檚 really a question of comparative risk.
Hydrogen is easy to ignite, but it鈥檚 buoyant and dissipates rapidly. And if it
is caught in a confined space, it requires more oxygen to burn than oil does.
鈥淗ydrogen is less hazardous than gasoline,鈥� says Amory Lovins of the non-profit
Rocky Mountain Institute in Colorado, which specialises in the future design of
cars.

The key questions today are not so much 鈥淒o we want a hydrogen economy?鈥�, as
鈥淲hat sort of hydrogen economy do we want, and how do we get there?鈥� Do we make
the new wonder-fuel from petrol, natural gas, methanol, biomass or water? Do we
make it in centralised hydrogen factories, on the forecourts of service stations
or under the bonnet? How do we store it? And do we put it in conventional
internal combustion engines or fuel cells?

The world鈥檚 biggest car makers are busy drafting a road map to the
hydrogen-fuelled future. But nobody yet seems sure of the way. BMW is betting on
an internal combustion engine that burns hydrogen, claiming it鈥檚 the only way to
deliver the acceleration and responsiveness drivers are used to. But most
believe that the internal combustion engine, with its Heath-Robinson assembly of
transmission and drive shafts, is too inefficient. It converts barely 20 per
cent of its fuel鈥檚 energy into traction. Electric engines can have an efficiency
of up to 80 per cent. But batteries don鈥檛 deliver enough power for their weight
and need frequent recharging. So attention is increasingly focusing on electric
engines without batteries.

Plan A, the so-called hybrid engine, has already been on Japanese roads for
three years, under the bonnet of Toyota鈥檚 Prius model. It鈥檚 a petrol-burning
engine hooked up to an electric motor. The engine doesn鈥檛 drive the car
directly, but generates electricity, which is stored in a battery and released
as necessary to drive the car. So the petrol engine can always operate at its
most efficient speed, rather than surging or slowing to the demands of road and
driver. Result: fuel savings of 10 to 20 per cent and similarly reduced
pollution. It鈥檚 a start.

Further improvements could be made if the engine burnt a cleaner fuel. But
the smart money is on something more radical. That something was invented way
back in 1839 by Welsh physicist Sir William Grove: a fuel cell that runs on
hydrogen.

Many types of fuel cell have been developed over the years (see 鈥淔uelling the
future鈥�). But until recently they were too large, cumbersome and low on
power to run a car鈥攅ven after NASA tinkered with them to provide
pollution-free electricity inside the Apollo spacecraft.

The breakthrough came in the mid-1990s when a small company, Ballard Power
Systems of Vancouver in Canada, dramatically improved their power-to-volume
ratio. Up to that point, fuel cells delivered around 167 watts per litre. A car
engine built with these would commandeer the entire boot and back seat. Around
five years ago Ballard achieved 1000 watts per litre. For the first time, fuel
cells could fit under the bonnet. The company鈥檚 latest cell, the 鈥淢ark 900鈥�,
delivers 1310 watts per litre, powerful enough to make a 75 kilowatt (100 brake
horsepower) engine that fits comfortably inside a car.

Soon fuel cells will be on the highways. Ballard vice-president Paul
Lancaster promises that by 2004 a quarter of a million fuel cells will be
rolling out of its $400 million production plant every year. And he has
development deals to put them in cars made by Ford, General Motors, Toyota,
DaimlerChrysler, Nissan and Honda.

Ferdinand Panik, director of DaimlerChrysler鈥檚 fuel-cell project in Germany,
reckons hydrogen fuel cells will power a quarter of new cars worldwide by 2020.
It could be a lot sooner, especially now oil companies are lining up too. Shell
gave its blessing last March when Don Huberts, chief executive of Shell Hydrogen
in Amsterdam, predicted hydrogen would be the world鈥檚 number one fuel in the
21st century.

Ballard鈥檚 proton exchange membrane fuel cell converts fuel into power twice
as efficiently as an internal combustion engine while producing no noise or
noxious emissions. No wonder hydrogen fuel cells have a green halo. British
transport minister Gus MacDonald declared in December last year that fuel cells
would allow more than half of new British cars to be 鈥減ollution-free鈥� within a
decade. But hang on a moment. Fuel cells are a major advance because they are a
more efficient way of powering a vehicle. But 鈥減ollution-free鈥� they are not.

This is what we might call the 鈥渆lectric kettle problem鈥�. Fuel cells, like
electric kettles, emit only steam. But kettles are powered by electricity
generated in power stations that burn coal or oil. And fuel cells are powered by
hydrogen made by . . . well, by what? You cannot mine hydrogen or pluck it from
the air. It has to be manufactured. And the method of manufacture determines the
pollution. 鈥淚f we make hydrogen from the wrong fuel source, such as gasoline,
the green halo could vanish,鈥� says Rob Macintosh of the Pembina Institute for
Appropriate Development in Alberta.

There are two main ways of producing hydrogen. The first is electrolysis,
passing an electric current through water to split it into hydrogen and oxygen.
This requires large amounts of electricity, most of which is generated by
burning fossil fuels such as coal or oil. Use this to run a car and there鈥檚
little, if any, gain. To make environmental sense, the electricity has to be
generated from renewable resources (see 鈥淢ake hydrogen while the Sun shines鈥�).

The second route to hydrogen is to refine it鈥攅ither from a conventional
hydrocarbon or a novel source such as plant matter. This refining, or 鈥渟team
reforming鈥�, can be done in a number of ways: centrally at a refinery for
delivery by pipeline to service stations; at the filling station itself, using
hydrocarbons trucked or piped in; or on-board the car in a small 鈥渞eformer鈥� that
directly supplies the fuel cell. In each case, reforming combines a hydrocarbon
and water at high temperatures to produce carbon dioxide and hydrogen. The
trick, in environmental terms, is to choose a hydrocarbon that produces maximum
hydrogen for minimum carbon dioxide. Natural gas, which is mostly methane
(CH₄), is the best because it has the highest possible hydrogen-to-carbon ratio.

Green dream

There are other potential methods of hydrogen manufacture, such as mimicking
photosynthesis, using heat or high-energy particles to split water, or even
harnessing bacterial enzymes. But all are still largely confined to the lab.
Reforming natural gas, however, is already widely used in the production of
chemicals.

But which of the options would be best for the environment? Macintosh accepts
that 鈥渢o be truly pollution-free, the hydrogen must come from a renewable
source, such as solar or wind power鈥�. The green dream of electrolysis using a
renewable energy source is technically feasible, but not yet economically
viable. So Macintosh has analysed available technologies, using the test of how
much greenhouse gas would result from making and using the fuel needed to drive
a standard vehicle鈥攁 Mercedes A-class hatchback鈥攐n a 1000-kilometre
drive across Canada.

Worst, not unexpectedly, was the regular gasoline-burning car. It emitted 248
kilograms of CO₂, most of it in the exhaust gases. Next worst was a
fuel-cell car with an on-board reformer that turned gasoline into hydrogen. This
so-called 鈥減ollution-free鈥� vehicle chalked up 193 kilograms, mostly from the
reformer. After that came on-board reforming of methanol, the chemical many
fuel-cell pioneers see as the most likely route to mass-produced fuel-cell cars.
In Macintosh鈥檚 study, methanol outperformed gasoline, producing 170 kilograms of
CO₂. But it lagged way behind the vehicles carrying hydrogen made from
natural gas reformed either on forecourts or at a central facility. These
emitted between 70 and 80 kilograms of CO₂鈥� 70 per cent less than
gasoline. Macintosh only looked at greenhouse gas emissions, but he reported
that smog-creating emissions would show a similar profile.

Even if the problem of hydrogen generation is cracked, there are still
roadblocks between here and a hydrogen economy. One is storage (see 鈥淲here to
keep it鈥�). Another is the need to create a new infrastructure for
producing and distributing bulk hydrogen, costing perhaps trillions of dollars.
This looks especially problematic, but there are potential solutions.

One is kick-starting the hydrogen economy in smog hot spots, such as southern
California, or in areas of abundant 鈥済reen鈥� energy for hydrogen production, such
as Iceland. Another is to make the transition in stages, perhaps by
concentrating first on fuel-cell vehicles with on-board hydrocarbon
reformers.

But which hydrocarbon would make the best stepping stone? Much of the car
industry favours methanol. The argument is that methanol is a liquid, so is
easier to manufacture and handle in bulk than hydrogen while still offering
significant environmental advantages over oil.

Last year, Ballard signed a deal with Methanex of Vancouver, the world鈥檚
largest methanol producer, to set up a prototype distribution system in Canada.
Ballard is backing a similar project in the US along with the California Air
Resources Board, Ford and DaimlerChrysler.

Macintosh, though, says this is misguided. 鈥淯nfortunately, on-board
processing of methanol fuel does not offer anything near to the life-cycle
greenhouse gas advantage of natural gas reforming,鈥� he says. It also requires a
whole extra stage of manufacture, a reformer in every car, and its own
distribution and storage systems. Methanol is corrosive so would have to be held
in reinforced tanks. It鈥檚 also water soluble, which means leaks into groundwater
would be hard to contain. Paul Histon of BP Amoco fears setting up a system for
shipping methanol round the country, only to have to move again to a hydrogen
distribution system a few years later. 鈥淲e only want one big change,鈥� he says.
鈥淚f it鈥檚 going to be hydrogen, let鈥檚 get on and do it.鈥�

The logical solution, argues Macintosh, is for cars to fill up with hydrogen
produced on garage forecourts from natural gas. This is cheap, because the
natural-gas distribution network is already in place. It is the most
environmentally friendly technology currently available. And it is very easy.
Indeed, you might not even need filling stations. Your office or neighbourhood
could do it (see 鈥淔ill 鈥榚r up鈥�). A reformer the size of a water heater
鈥渃an produce enough hydrogen to serve the fuel cells in dozens of cars鈥�, says
Amory Lovins. The scenario is also flexible. As demand grows, bulk suppliers of
hydrogen might get interested, developing pipeline networks if they felt they
could undercut local production.

Natural gas, says Lovins, offers 鈥渁 long bridge to a fully renewable energy
system鈥�. And there could be unexpected bonuses along the way. Robert H. Williams
of Princeton University鈥檚 Center for Energy & Environmental Studies, sees
potential for the owners of gas fields turning their product into hydrogen at
the wellhead. That way, the resulting CO₂ emissions could be injected
right back into the emptying well.

But journey鈥檚 end will be a true hydrogen economy, in which the link to
fossil fuels has been cut for good. Greens and industrialists alike are
beginning to glimpse the day when renewable energy鈥攚hether solar or wind,
geothermal or hydroelectric鈥攊s ready to take over electrolytic production
of hydrogen from water. Indeed, manufacturing hydrogen may turn out to be the
most effective use of renewable energy. For it gets round the inconveniently
intermittent nature of many sources鈥攁vailable only when the wind is
blowing or the Sun is out. Hydrogen will, in effect, be able to store that
energy.

Lovins sees hydroelectric dams, in particular, becoming 鈥渉ydro-gen鈥� plants.
They have the unique advantage of bringing together abundant water and
electricity supplies and could 鈥渆arn far higher profits by selling not
electricity but hydrogen鈥攊n effect shipping each electron with a proton
补迟迟补肠丑别诲鈥�.

This strategy even gets round one of the major problems of
hydroelectricity鈥攖he need to flood large areas of land to store water.
Reservoirs are only needed so that electricity can be generated on demand. But
the need disappears if that electricity can be generated 鈥渁t nature鈥檚
convenience鈥濃�攙arying according to rainfall鈥攁nd its energy stored as
hydrogen. Large reservoirs could be replaced in many places by 鈥渞un-of-river鈥�
hydroelectric plants that take power from passing water without damming it.

The hydrogen age could be closer than we think. Certainly, the route map is
slowly emerging. But who will get on the road first? Right now, revving up at
the front of the grid is the country with one of the largest hydroelectric
reserves in the world. Plucky Iceland.

SAY goodbye to smoky exhaust fumes, noisy revving engines and oil changes.
The fuel cell will end them all. It鈥檚 a continuously regenerating
battery鈥攁 box that chemically combines hydrogen and air to create an
electric current. More importantly, it promises a car engine with few moving
parts and nothing but pure, clean water dripping out of the tail pipe.

There are many types of hydrogen fuel cell, but they all have the same basic
architecture. A single cell consists of two electrodes separated by an
electrolyte鈥� a solution or molten substance that conducts electricity. A
catalyst, typically platinum, coats the electrolyte. This set-up enables the
electrochemical equivalent of combustion to take place: hydrogen reacts with
oxygen to release energy and water. But in a fuel cell there鈥檚 no flame.
Instead, the energy is released by feeding electrons through an external circuit
(see Diagram).
This generates the current that drives the car. Although a single
cell only creates about 0.7 volts, a stack of cells will give you enough juice
to run a car.

The best type of fuel cell for a vehicle engine is the proton-exchange
membrane cell. Its electrolyte is a thin plastic sheet that lets protons through
but blocks electrons and oxygen. PEMs are ideal for cars because they work at
relatively low temperatures鈥攂etween 60 掳C and 80 掳C. Other cells
perform at far higher temperatures, making for engines that take a long time to
warm up, cost a lot to build and suffer terrible wear and tear.

But there is a price to pay to keep the engine running cool. PEM fuel cells
are extremely fussy eaters, intolerant of anything other than 100 per cent pure
hydrogen. The impurities that creep into 鈥渞eformed鈥� hydrogen (made from
hydrocarbons such as methanol) can quickly poison them. You can get around this
by carrying a tank of hydrogen with you, but this is potentially hazardous.
鈥淔uel storage is the Achilles鈥� heel,鈥� says Scott Samuelson, director of the
National Fuel Cell Research Center at the University of California, Irvine.

Cells with higher operating temperatures鈥攁nything up to 1000
掳C鈥攁re more tolerant of impurities, as any contaminants are scorched
off the catalyst鈥檚 surface. But they have drawbacks that make them unsuitable
for cars. Phosphoric acid cells have an acidic liquid electrolyte鈥攏ot
something you want sloshing around your engine. Molten carbonate cells run at a
hot 700 掳C, and alkaline cells are poisoned by carbon dioxide鈥攑retty
hard to avoid unless you have an airtight engine. These cells may be good for
space applications, but they are unlikely to make it into cars.

One promising alternative is the solid oxide fuel cell (SOFC). Its big
advantage is that it can run on fossil fuels like natural gas, ethane and
butane, as well as hydrogen. SOFCs operate a little differently from the norm.
The electrolyte is a solid, typically a zirconium oxide ceramic. Negatively
charged oxygen ions flow across the electrolyte to react with the fuel. Because
they use fossil fuels, your car would still spew carbon dioxide, but only about
half as much as an internal combustion engine produces.

Operating temperatures for SOFCs have recently been lowered to 500 掳C,
but that鈥檚 still too high for cars. They鈥檙e also expensive, with a projected
price tag of $400 per kilowatt compared with around $50 per
kilowatt for a PEM cell. 鈥淚t might be overcome,鈥� says Jim Ohi from the US
Department of Energy鈥檚 National Renewable Energy Laboratory in Colorado. But
SOFCs are more likely to be used in power stations. Nicola Jones

EMPLOYEES of the SunLine Transit Agency of Thousand Palms, California, are
looking forward to the day their parking lot gets a roof, and not just because
it will stop the desert sun from broiling their dashboards. The roof could also
propel them to the forefront of an energy revolution. It will be made of solar
panels, which SunLine plans to use to generate electricity. This, in turn, will
be converted into pure, clean hydrogen.

SunLine runs public bus services in the Coachella Valley, a desert resort in
southern California renowned for its clean air and clear blue skies. 鈥淚t鈥檚
gorgeous here,鈥� says Catherine Rips, the company鈥檚 marketing director, 鈥渁nd we
want to keep it that way.鈥� The best way to achieve that, SunLine reckons, is to
banish fossil fuels and turn the area into Hydrogen Valley.

In 1994, the company took the first step towards this smogless future,
scrapping its entire fleet of diesel buses and switching overnight to compressed
natural gas. It has now embarked on the transition to hydrogen. In April 2000 it
opened a small hydrogen plant at Thousand Palms, powered by 195 square metres of
solar panels. The parking-lot roof will add another 2140 square metres of
electricity-generating capacity, turning Thousand Palms into one of the world鈥檚
largest solar hydrogen stations.

Electricity from the solar panels feeds into two electrolysers. These
generate hydrogen from water with no nasty carbon dioxide emissions. The
hydrogen is compressed and stored, then pumped into SunLine鈥檚 hydrogen-powered
fleet: three golf carts, a two-seater car, a pickup and a hydrogen-powered bus
that SunLine is road-testing for Xcellsis of Germany, which makes fuel-cell
engines. SunLine also has two Hythane buses, which run on a mixture of 80 per
cent methane and 20 per cent hydrogen. It has even opened a hydrogen filling
station to the public, although as yet there are no privately owned hydrogen
cars on the road.

While SunLine waits for the rest of the Coachella Valley to catch up, it will
run the project as an experiment in renewable hydrogen generation. The solar
arrays include several different kinds of panels to find out which work best.
Despite its name, SunLine isn鈥檛 wedded to solar power. It also has a hydrocarbon
reformer that makes hydrogen from hydrocarbons, and plans to test wind
turbines.

The biggest question of all, however, is economic. Can solar hydrogen compete
with fossil fuels? SunLine has yet to publish any figures, so it鈥檚 hard to say
for sure. But Rips thinks not. Renewable hydrogen, she says, is probably 鈥渘ot
even close to being competitive鈥�.

That was also the conclusion of Europe鈥檚 largest solar hydrogen experiment,
which ran from 1986 to 1999 in the Bavarian town of Neunburg vorm Wald. The
Solar Hydrogen Project achieved all its technical goals but shut down at the end
of last year without approaching economic parity. 鈥淚t鈥檚 simply too expensive,鈥�
says Hans Reiner of the project鈥檚 main shareholder Eon Energy, who ran the
technical side of the project.

A big problem is the price of solar panels. SunLine鈥檚 roof, for example, will
cost $139,500 and last 20 years at best. Another disadvantage is that
fossil fuel production benefits from vast economies of scale, whereas renewable
hydrogen has only just got past the garden shed stage. That means it鈥檚 much
cheaper to generate hydrogen using electricity derived from burning oil. The
figures are so stacked against solar hydrogen that Eon Energy says it can鈥檛 give
a fair dollar-for-dollar comparison.

But that could all change once the hydrogen economy is in full swing. For
now, Eon says it will keep an eye on the market, biding its time until the
economics are right. Then it will dust off its technological know-how and get
down to business.

And solar power isn鈥檛 the only game in town for making renewable electricity.
As Iceland intends to prove, hydroelectric power is also a contender. You don鈥檛
even have to generate electricity to make hydrogen. CSIRO, Australia鈥檚 national
research organisation, for example, is harnessing the Sun鈥檚 heat directly to
reform methane into hydrogen. It鈥檚 not as clean as electrolysis鈥攖he
reaction also generates CO₂鈥攂ut it鈥檚 more efficient than burning
the methane.

CSIRO鈥檚 experimental reactor, perched on a hill above Sydney, is a 12-metre
dish lined with mirrors. These track the Sun across the sky and focus its heat
onto reaction vessels. That provides enough energy to convert a mixture of
methane and water into hydrogen and CO₂. During its first day of
operation last month, the reaction ran at 650 掳C, but in summer that could
rise to as high as 1000 掳C. Graham Lawton

THERE are significant problems with storing hydrogen. A tank full of hydrogen
gas at atmospheric pressure would need to be 3000 times larger than a gasoline
tank for a similar journey. You could liquefy and compress the hydrogen, but
this is costly and uses between 20 and 40 per cent of the energy eventually
stuffed into the tank. Also, the tanks themselves are robust and
heavy鈥攈ydrogen only accounts for between 5 and 7 per cent of their weight
even when they鈥檙e full. For buses and trucks this isn鈥檛 a problem. But it
effectively limits the range of a hydrogen car to half that of a regular one. So
the search is on for an alternative.

One idea is to store hydrogen between atoms of granular metal. When heated,
some metals absorb up to a thousand times their own volume of hydrogen gas. On
cooling, the hydrogen is locked in, but can be released again by
heating鈥攑erhaps using the car engine itself. Weight for weight, however,
these storage systems are not much better than a pressurised tank.

Another suggestion is to enclose hydrogen within carbon
nanotubes鈥攕heets of carbon atoms rolled into minuscule tubes. Researchers
have managed to get nanotubes to absorb one hydrogen atom for every two carbon
atoms. But this still means that only 4 per cent of their weight is
hydrogen鈥攚orse than with other methods. A competing technology, using
nanofibres made of graphite, has been reported to be at least 10 times better
than liquefaction and compression, with hydrogen making up as much as 75 per
cent of the fuel store (快猫短视频, 21 December 1996, p 20). This
would allow a hydrogen-powered car to travel up to 8000 kilometres without
refuelling. But co-inventor Terry Baker of Northeastern University in Boston,
Massachusetts, says there is a serious problem. 鈥淚t turns out the nanofibres
don鈥檛 just store hydrogen, they also attract water vapour, which they absorb
preferentially over hydrogen. Right now, our invention would work fine in the
desert but not anywhere else. I鈥檓 still enthusiastic but we need to step back
and do the fundamental science first.鈥�

Thorsteinn Sigfusson, chairman of Iceland New Energy, says storage is the
number one problem for his country鈥檚 plans. 鈥淲e are closely watching research
into both metal and carbon nanofibre storage,鈥� he says. 鈥淭hey could be crucial.鈥�
Fred Pearce

IN THE good old days you sat in the car while cheery souls washed your
windows and filled your tank with fuel. Now you have to get out and work the
pump yourself, before paying the unsmiling cashier. Soon, you may have to deal
with an ice-cold robot.

In the post-petrol world, robotic pump attendants will be a common sight. And
you鈥檒l be more than happy to let them fill your car for you. Chances are, the
fuel you鈥檒l buy will be liquid hydrogen at 鈥�253 掳C.

The world鈥檚 first robotic hydrogen station opened to the public in May 1999
at Munich International Airport in Germany. As yet, it hasn鈥檛 served a private
customer. But the robots have been kept busy refuelling a fleet of 15 specially
adapted BMWs that are used to ferry visitors between the airport and BMW鈥檚
Munich headquarters.

To fill up, drivers simply pull up to the pump and press a button on their
dashboard. They then stay in their seats while a robotic arm uses lasers to
locate the fuel tank. The arm slots into the fuel cap, opens it with a twist and
starts pumping in the hydrogen. 鈥淚t all looks very futuristic,鈥� says Thomas
Steffes from BMW.

The cars have insulated 140-litre tanks, which take about three minutes to
fill and hold enough hydrogen to travel over 300 kilometres. That鈥檚 not bad, but
it still can鈥檛 compete with petrol. The BMWs, which are hybrids capable of
burning both hydrogen and petrol, can go twice as far on a 95-litre tank of
conventional fuel. And petrol is cheaper. At Munich airport, a litre of petrol
costs 0.6 Deutschmarks before tax, compared with 1.1 Deutschmarks for a litre of
hydrogen.

For BMW, though, this is just a loss-leader. The company envisages a hydrogen
filling station in every European capital by 2005 and an 鈥渁dequate network鈥� of
stations across the continent by 2010. And it intends to drum up plenty of
customers. 鈥淥ur vision is that, from the year 2020, more than a third of all BMW
vehicles sold in Europe will be hydrogen-powered,鈥� says the company鈥檚 chairman,
Joachim Milberg.

The US also has a fledgling hydrogen filling station network. In August 1999,
Ford opened an experimental station at its research laboratory near Detroit,
Michigan, the heart of car-mad America. In April, the SunLine Transit Agency
opened the first public station in the US (see 鈥淢ake hydrogen while the Sun
shines鈥�). And on 1 November, the California Fuel Cell Partnership opened
another public station in West Sacramento, California, backed by an impressive
coalition of car and oil companies including Ford, DaimlerChrysler, General
Motors, Volkswagen, Honda, Toyota, Nissan, Hyundai, Shell, Texaco and BP
Amoco.

It鈥檚 possible, however, that you might never need to visit a hydrogen
station. Ford is also testing small, portable electrolysers for home use. These
鈥減ersonal fuel appliances鈥�, made by Canadian company Stuart Energy Systems,
require no more than a 220-volt electrical supply and a hose. Stuart says
they鈥檙e as easy to recharge as a cellphone. Just connect it to your fuel cell
car at the end of the day and wait for it to refill with compressed
hydrogen.

Whichever technology wins out, the public will have to be convinced that
filling up with hydrogen is safe. BMW, which has conducted extensive safety
tests, is confident that the risk is 鈥渟imilar鈥� to that of other potentially
explosive fuels . . . like petrol. Rob Edwards