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HYDROGEN FUTURE FACTS AND FALLACIES Introduction

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					Hydrogen Future:, Aulice Scibioh & Viswanathan, Bulletin of the Catalysis Society of India,3(2004)72-81


              HYDROGEN FUTURE: FACTS AND FALLACIES
                         M. Aulice Scibioh and B. Viswanathan
 Department of Chemistry, Indian Institute of Technology,Madras – 600 036, India.
                    E-mail : bvnathan@iitm.ac.in, bvis@chem.iitm.ac.in
Abstract: A transition to a ‘hydrogen economy’ is a sea change in our energy
infrastructure and is not to be taken lightly. As an energy carrier, hydrogen is to be
compared to electricity, the only wide spread and viable alternative. When hydrogen is
employed to transmit renewable electricity, only 50% can reach the end user due to losses
in electrolysis, hydrogen compression and the fuel cell.        The rush into a hydrogen
economy is neither supported by energy efficiency arguments nor justified with respect to
economy or ecology. In fact, it appears that hydrogen will not play an important role in
a sustainable energy economy because the synthetic energy carrier cannot be more
efficient than the energy from which it is made. Renewable electricity is better distributed
by electrons than by hydrogen. Consequently, the hasty introduction of hydrogen as an
energy carrier cannot be a stepping stone into a sustainable energy future. The opposite
may be true.      Because of the wastefulness of a hydrogen economy, the promotion of
hydrogen may counteract all reasonable measures of energy conservation. Even worse,
the forced transition to a hydrogen economy may prevent the establishment of a
sustainable energy economy based on an intelligent use of precious renewable resources.
This article is meant to direct attention to some fundamental problems of a Hydrogen
Economy.
Key words: Hydrogen economy, hydrogen energy

Introduction                                            into the speeches of industry executives.
                                                        Greenery, innovation and market forces
It is interesting to watch the growing                  are shaping the future of our industry
debate over the future of energy. Many                  and propelling us inexorably toward
forecasts predict that the demand for                   hydrogen energy.
energy will grow by 50 percent over the
next two decades. Natural gas reserves                  Consequently, hydrogen is the topic of
are becoming a concern in many nations.                 the day. The ‘Hydrogen Initiative’ led
The situation in the Middle East and                    politicians from many countries to
Asia is to put it mildly, creating                      follow suit without questioning the
instability for the future reliability of oil.          promises of the hydrogen enthusiasts.
United States and Ontario has focused                   Hydrogen is presented as the ultimate
attention on problems with the grid that                solution to all energy problems. The
feeds our growing appetite for electricity.             equation: ‘hydrogen + air = electricity +
Continued technological advances in                     drinking water’ is certainly fascinating.
renewables and distributed generation                   Representatives from industry or the
options are new possibilities and options.              public are seen on television drinking the
The idea of using hydrogen - the                        drip-off from tail pipes of hydrogen fuel
simplest, lightest and most abundant                    cell vehicles. Indeed, the conversion of
element in the universe - as a primary                  hydrogen back to its natural state (water)
form of energy is beginning to move                     is clean, but how benign is the
from the pages of science fiction and                   fabrication and distribution of this


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synthetic energy carrier? Certainly,            economy are mentioned - is where will
hydrogen is the most abundant element           the hydrogen actually come from?
in the biosphere.         Unfortunately, it     Hydrogen is an energy carrier and not a
appears only in chemical compounds              freely available natural resource in any
such as hydrogen oxide, commonly                useable form - just like the other energy
known as water.           More energy is        carrier electricity it has to be produced
needed to split water than can ever be          somehow.        Advocates of renewable
retrieved from the generated hydrogen.          energy would be well advised to
How much energy is really consumed to           examine the issues and to ensure that
make, package, distribute and transfer          solar and wind technologies are not
hydrogen?        Where does the energy          over-looked or under-valued in the years
come from? How efficient is the                 to come as a source of hydrogen.
distribution of the lightest, thus most         There is no dispute that hydrogen offers
impractical of all energy gases? How            major benefits to the world economy and
much energy is needed to run a                  environment.       Its use in transportation
hydrogen economy?           Can we afford       reduces the emission of NOx and SOx
such a wasteful hydrogen economy at all?        pollutants, which offers significant air
These questions need to be answered             quality advantages in urban areas.
before investments are made in a                However, if the original source of
hydrogen future.       It will cost trillions   hydrogen is produced from conventional
of dollars to convert the entire energy         sources such as fossils then in reality
system to hydrogen. Thus, it is simply          these emissions and other pollutants are
due diligence to question the optimistic        technically just shifting from the tail
claims of the hydrogen promoters before         pipe to the original source of hydrogen
tax money is spent on research,                 production.
development and hardware. Any new               Natural gas has been already referred as
energy technology must be based on a            a ‘clean’ fuel (since it is ‘cleaner than
sound platform of science, engineering          coal’), so the use of gas as a feedstock
and economics.                                  for hydrogen means the resulting energy
World governments have committed                is ‘cleaner’ at point of consumption.
billions of dollars/euros to the                With the exception of sequestration it is
development        of      a      hydrogen      agreed that hydrogen can never be
infrastructure, with a focus on fuel cells      totally ‘clean’ unless it is electrolyzed
as the delivery mechanism.               This   using a renewable energy technology,
decision to forge a transition to hydrogen      such as wind turbines or solar panels.
has been made, and it is unlikely that the      Despite losses in conversion efficiency,
evolution could be stopped now, even if         fuel cells also offer load levelling
people wanted.       The logic: the world       possibilities that may bode well for
needs a secure future supply of clean           renewables.       Few people forecast the
energy, and hydrogen is the most                use of fuel cells in centralized energy
abundant element in nature. However,            plexes, and it is safe to suggest that any
this logic obfuscates a number of               paradigm shift which encourages society
important points, and is based on some          to break away from the mold of large
potentially slippery foundations.          A    centralized generating facilities in favor
key issue that is often not addressed           of distributed generation (DG) options is
when fuel cells and the hydrogen
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bound to encourage greater uptake of          hydrogen, i.e. the transfer of chemical
renewables.                                   energy from one substance to another,
                                              cannot improve overall efficiency or
Thirty years were passed since the            reduce the emission of greenhouse gases.
beginning of the Hydrogen Energy              Carbon dioxide is released into the
Movement in 1974. Over the past three         atmosphere when natural gas is reformed
decades,        there     have        been    to hydrogen or when natural gas is burnt
accomplishments on every front - from         in furnaces. Hydrogen is clean only if
the acceptance of the concept as an           it is made from renewable electricity.
answer to energy and environment              However, electricity from any source,
related global problems - to research,        conventional or renewable, can be
development and commercialization.            transmitted to the consumer by power
The Hydrogen Energy System has now            lines, pollution-free and with a relatively
taken firm roots. Activities towards the      high efficiency. So why use electricity
implementation are accelerating. The          to split water by electrolysis, spend more
various activities and accomplishments        electricity to package hydrogen by
over this period are listed in Table. 1.      compression or liquefaction to make it
Hydrogen may yet to find an important         marketable, use energy to distribute it to
place in our energy future.         We are    the consumer and convert it back, with
focusing on building the knowledge and        considerable losses, to electricity in
capabilities that will be needed in the       stationary or mobile fuel cells?       In a
future should hydrogen enter the supply       sustainable future, cheaper power will
chain as a transportation fuel.               come from the grid.       Also, renewable
However, the surge of interest in a           electricity will soon replace fossil fuels
‘hydrogen economy’ is based on visions        which are now used for stationary power
than on facts.          Since, hydrogen       generation or space conditioning. The
economy would be based on two                 replaced oil will probably be sold at
electrolytic processes both associated        fuelling stations to power vehicles. For
with heavy energy losses: electrolysis        many years this substitution process will
and fuel cells.     For a secured energy      dominate the transition within the energy
future, we need new energy sources, not       market from stationary to mobile
new energy carriers.          Because the     applications of fuels. The most important
investment in infrastructure is substantial   source of petroleum fuel will be the
and therefore irreversible, it is important   improvement of building thermal
that the choice we make is a proper one       standards. For years to come, hydrogen
for the future.                               has to compete with replaced fossil fuels.
                                              But will hydrogen be a promising option
Unfortunately, hydrogen is not a new          after the depletion of oil wells, when
source of energy, but merely another          renewable energy has become abundant?
energy carrier. Like electricity, it
provides a link between an energy             Energy     carrier:    Electrons     vs.
source and energy consumers.         The      Hydrogen:        Renewable electricity
energy source may be a chemical energy        appears more promising source of
carrier such as natural gas, coal and oil,    energy for the future. Like electricity
or electricity.    With few exceptions,       from     decentralized     cogeneration,
the conversion of fossil fuels into           renewable electricity will be generated
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near consumers’ sites to minimize             generated will be supplied to the grid.
transmission losses.  Excess power            Electrolysis and fuel cells may be used
             Table 1. Developments in Hydrogen Movement from 1974 - 2004

           Activities                                  Details
International Conferences   THEME conference, 1974
                            1 WHEC, Miami Beach, 1976
                            2 WHEC, Zurich, 1978
                            3 WHEC, Tokyo, 1980
                            4 WHEC, Pasadena, 1982
                            5 WHEC, Toronto, 1984
                            6 WHEC, Vienna, 1986
                            7 WHEC, Moscow, 1988
                            8 WHEC, Honolulu,1990
                            9 WHEC, Paris,1992
                            10 WHEC, Cocoa Beach,1994
                            11 WHEC, Stuttgart, 1996
                            12 WHEC, Buenos Aires, 1998
                            13 WHEC, Beijing, 2000
                            14 WHEC, Montreal, Canada, 2002
                            15 WHEC, Yokohama, Japan, 2004
Concepts                    Acceptance of Hydrogen Energy, Hydrogen Economy &
                            Hydrogen Energy System
Organizations dedicated to I.A.H.E,
Hydrogen Energy             H.E.S.S. (Japan)
                            National Hydrogen Association (USA)
                            American Hydrogen Association
                            Canadian Hydrogen Association
                            China Hydrogen Association
                            German Hydrogen Association
                            Indian Hydrogen Association
                            Italian Hydrogen Association
                            Korean Hydrogen Association
                            Mexican Hydrogen Association
                            Swedish Hydrogen Association
                            Turkish Clean Energy Association
                            Clean Air Now (USA)
                            WCTC-CMDC (Switzerland)
Periodicals  on    Hydrogen Int. J. Hydrogen Energy
Energy                      Hydrogen Information (France)
                            H.E.S.S. Journal (Japan)
                            The Hydrogen & Fuel cell letter (USA)
                            Hydrogen Today (USA)
                            Fuel Cells Bulletin (U.K)
                            E.E.T.E. (Russia)
Books on Hydrogen Energy    Proceedings: WHEC (>40 Vols)
                            Books in: English, Japanese, German, Russian, French,
                            Italian, Spanish, Polish, Portuguese, Turkish, etc.,
Visual programs on Hydrogen Beyond Tomorrow
Energy                      Element One
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                                Energy from Water
                                Fire in the water
                                Hydrogen: One Solution
                                Hydrogen Safety
                                Invisible Flame
                                The Dawn of Hydrogen Age
                                The Green Car
                                Wake up, U.S.A
Internet Sites                  www.iahe.org
                                www.dwv-info.de
                                www.ttcorp.com/nha
                                www.cleanair.org
                                www.h2eco.org
                                www.fuelcells.org
                                www.hyweb.deindex.e.html
                                www.eren.doe.govhydrogeninfonet.html
Companies and Organization Tokio Electric Utility, Kansai Electric Power, International
involved in Hydrogen, Fuel Fuel Cells, Toshiba, Siemens/Westinghouse
Cell       Electric      Power Plug Power/GE, Fuel Cell Energy Corp., EPRI
Generation
Companies       involved     in BMW, Daimler-Chrysler, Ford, General Motors, Ballard,
Hydrogen-Fuelled Vehicles       Energy Partners, H-Power, ZEVCO, Mazda, Honda,
(Land Vehicles)                 Toyota, Nissan
Naval       Application      of German Navy, Australian Navy, Canadian Navy
Hydrogen                        Italian Navy
Hydrogen in Space Programs      U.S.S.R, U.S.A, Russia, Europe, China, Japan, India
Hydrogen in Aerospace planes U.S. Shuttle, Russian Shuttle, European Sanger, National
                                aerospace plane: Boeing, Lockheed, McDonnell Douglas’
                                Rocket dyne, Rockwell International, Pratt& Whitney
Hydrogen           in      Air Grumman Cheetah (Conrad Plane)
Transportation                  Tupolev 155
                                German-Russian Cooperation
                                Airbus Program
                                Japan-Hypersonic
Hydrogen               Hydride Products/Developments:
Applications                    Batteries, Computer batteries, Electric car batteries, Air-
                                conditioning, Refrigeration, Heat pumps, Hydrogen
                                Storage
Hydrogen              Catalytic Products/Developments:
Combustion Applications         Kitchen appliances, Cookers, Ovens, Water heaters, Space
                                heaters
                                Companies:
                                Fraunhofer Institute, Hydrogen Appliances

for temporary energy storage with
hydrogen, but, for overall efficiency,              by optimized power transmission
renewable electricity will be transmitted           between power plant and consumer.
directly by electrons and not by synthetic          This figure is lower for shorter
chemical energy carriers.          Today,           transmission distances. However, if
around 10% of electrical energy is lost             renewable electricity is converted to
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hydrogen, and hydrogen is subsequently        hydrogen economy will be extremely
reconverted       to   electricity,    then   wasteful compared to today’s energy
significantly more energy is needed to        system and to a sustainable energy future
drive the process. In fact, only about        based on the efficient use of renewable
25% of the original electrical energy         energy, i.e. the direct use of electricity
may be recovered by the consumer in           and liquid fuels from biomass.
stationary and mobile applications. At
first glance, this may sound unbelievable,
but the high losses are directly related to
the two electrochemical conversion
processes and the difficulty of
distributing the light energy carrier.
Compared to natural gas, packaging and
distribution of hydrogen requires much
more energy. The energy consumption
associated with all significant stages of a
hydrogen economy was analyzed and the
results     surprised    the      hydrogen
community worldwide.           The energy     In Fig 2, renewable electricity is
consumed at all the significant stages of     symbolized by wind turbines.       Let us
a hydrogen economy is given in Table 2.       assume that the power output of one
In most of the cases, electricity is          wind turbines is supplied to a certain
consumed. nergy losses were calculated        number of consumers by electrons, i.e.
using the true energy content of              by conventional electric power lines. If
hydrogen, i.e. its higher heating value       hydrogen is used as the energy carrier,
(HHV) of 142 MJ/kg. A hydrogen                four wind turbines must be installed to
economy will be based on one or many          provide these consumers with the same
optimized mixes of these stages.              amount of energy. Essentially, only one
Hydrogen may be compressed to 100 bar         of these wind turbines produces
for distribution to filling stations in       consumer benefits, while the remaining
pipelines, and then compressed further to     three are needed to compensate the
850 bar for rapid transfer into pressure      energy losses arising from the hydrogen
tanks of automobiles. Liquefaction of         luxury. Electrical power can be
hydrogen may be preferred to                  transmitted by a modestly upgraded
compression        in  order     to    save   version of the existing power
transportation energy, or on-site             distribution system. For energy transport
production of hydrogen with less              by hydrogen, a new infrastructure must
efficient electrolyzers may offer             be established and, in addition, the
economic advantages over hydrogen             electricity grid must be extended to
production in large centralized plants        deliver power to all the active elements
and distribution by pipelines.       There    of the hydrogen infrastructure such as
are no general solutions. The energy          pumps and compressors, hydrogen
cascade of a representative hydrogen          liquefiers,   and    on-site   hydrogen
option in comparison with energy              generators.
transport ‘by electrons’ is illustrated in
Fig. 1. Whichever scheme is chosen, a         Hence, a sustainable energy future will
                                              be based on renewable energy from
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various sources. With the exception of
biomass, renewable energy is harvested
as electricity, with solar, wind, hydro or
ocean power plants. In addition, solar

                 Table 2 Energy Consumed at stages of a hydrogen
                Economy (HHV: Higher Heating Value of Hydrogen)

        Stage              Deatils           % of HHV   Energy Consumed
 AC-DC conversion       -                 5             Electricity
 Electrolysis           -                 35            Electricity
 Compression            200 bar           8             Electricity
                        800 bar           13            Electricity
 Liquefaction           Small plants      50            Electricity
                        Large plants      30            Electricity
 Chemical hydrides      CaH2,      LiH,   60            Electricity
                        etc.
 Road Transport         200 km, 200       13            Diesel fuel
                        bar               3             Diesel Fuel
                        200         km,
                        liquid
 Pipeline               2000 km           20            Hydrogen
 On-site generation     100 bar           50            Electricity
 Transfer               100 to 850 bar    5             Electricity
 Re-conversion          Fuel cell, 50%    50            Hydrogen
 DC-AC conversion       -                 5             Electricity
Hydrogen Future:, Aulice Scibioh & Viswanathan, Bulletin of the Catalysis Society of India,3(2004)72-81


thermal and geothermal power plants                     sustainable energy future electricity will
will also produce AC power. One may                     be the price-setter.     It will cost more
assume that 80% of the renewable                        than it does today, but it will be the
energy becomes available as electricity                 cheapest form of energy in the
while only 20% is derived from biomass                  commercial market.         Because of the
or used directly for heating.        This               energy losses associated with the
picture is a complete reversal of today’s               hydrogen economy, the following
scenario, which is characterized by 80%                 energy price relations may be expected
of energy being fossil-derived and only                 for electricity-derived hydrogen:        at
20% coming from physical sources.                       filling stations, hydrogen will cost at
Renewable energy will be precious and                   least twice as much as electrical energy
therefore should be distributed and used                from the grid electricity from hydrogen
intelligently. Wasteful electrochemical                 fuel cells will cost about four times as
conversion processes such as electrolysis               much as electricity from the grid.
and fuel cells will be avoided whenever                 Consequently, for stationary applications
possible.     Distribution losses will be               such as space heating, natural gas will
minimized by local or regional energy                   hardly ever be replaced by hydrogen, but
solutions.     Global energy exchange                   small electric heaters and heat pumps
comparable to transporting oil around                   will be used to condition well insulated
the world will not be practiced, because                buildings. Similarly, electric cars may
the transport of hydrogen requires too                  become the choice for short distance
much energy compared to the low                         commuting, because electric power from
energy content of the transported                       an outlet in the garage will cost only half
commodity. This is true for the transport               as much as hydrogen at the fuel station.
of compressed or liquefied hydrogen by                  Furthermore, the ‘battery-to-wheel’
pipelines, land vehicles and ships. In a                efficiency of electric cars is about 80%,
sustainable future, energy demand and                   while the ‘tank-to-wheel’ efficiency of
supply will be matched by strict energy                 fuel cell cars can barely reach 40%,
conservation in buildings, by reduced                   based on the higher heating value of
energy consumption in the transportation                hydrogen. The daily drive to work in a
sector and by the use of electricity                    hydrogen fuel cell car will cost four
wherever and whenever possible.                         times more than in an electric or hybrid
                                                        vehicle. The economic optimization
Cost of energy: As a simple                             clearly favours electric solutions.
representation, one can say that a                      A hydrogen economy will be
customer receives only 50% of the                       characterized by a massive increase of
original renewable electricity energy                   electric power needs. It is unlikely that
with hydrogen gas, and that losses rise to              this demand can be satisfied from
75% or higher when this hydrogen is                     renewable sources alone.         Coal-fired
converted back to electricity. Needless                 and nuclear power plants will continue
to say, the conversion is done by very                  to be in use with all the known
efficient fuel cells. Today, natural gas                consequences for the environment and
prices serve as reference for the cost of               for safety. Therefore, before a hydrogen
electricity. Based on its energy content,               economy is established, the source of
grid power is about four times more                     electrical energy has to be identified and
expensive than natural gas.In a                         developed. The installation of wind



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energy converters, solar power plants        economy. Although still too expensive,
and tidal power generators is essential      high-temperature fuel cells are clean
for a sustainable energy future.             converters     of    hydrocarbons      into
Together with the rational use of energy,    electricity. Also, high-temperature waste
renewable sources may be sufficient to       heat can be recovered easily for many
match the reduced energy demand              uses. Future will witness the potential of
worldwide. However, it is unlikely that      cogeneration with high-temperature fuel
renewable generation capacity can be         cells.In a distant sustainable energy
stretched threefold to cover the losses of   future, with most renewable energy
the hydrogen luxury. The conversion of       being harvested as electricity, the role of
electrical energy into hydrogen is not       cogeneration must be redefined. Because
wise at this time, nor will it ever be.      of its energy efficiency, cogeneration
                                             will remain important for biomass-
Hydrogen and cogeneration: Presently,        derived chemical energy.        This may
hydrogen is made from fossil fuels, i.e.     include the conversion of digester gas,
from energy carriers also used in most       biogas, etc. into power and heat. It may
cogeneration applications. There is no       also include thermal energy obtained by
indication that the hydrogen detour          combustion of wood waste, residues and
offers benefits over the direct use of       farmed bio-mass in steam power plants.
hydrocarbons with respect to overall         However, it is unlikely that hydrogen
efficiency and greenhouse gas emissions.     will be produced from biomass or by
Recent ‘well-to-wheel’ studies based on      electrolysis,to be subsequently converted
the true energy content of chemical fuels,   to electricity in cogeneration facilities.
i.e. on HHV, conclude that hydrogen is       Because of its inherent energy efficiency,
not a promising energy carrier. For years    cogeneration will continue to be one of
to come, hydrogen will not be able to        the key power generation technologies in
beat natural gas with respect to overall     asustainableenergyeconomy. Whenever
efficiency,    the     environment     and   electricity is produced by Carnot
economy.        Advanced         hydrogen    processes, the unavoidable waste heat
technologies such as fuel cells cannot       will be utilized for space conditioning,
compensate for the losses and energy         hot water or industrial processes.
consumption associated with hydrogen         Cogeneration technology will be further
production and distribution.      Polymer    developed and adapted to a variety of
electrolyte fuel cell co-generators in the   sustainable fuels from biomass.
200 kW class have hardly ever provided
line power at lower heating value (LHV)      Limitations of a Hydrogen Economy:
efficiency above 32%. Modern diesel          All losses within a Hydrogen Economy
engines, even micro turbines, show           are directly related to the nature of
better yields. But molten carbonate or       hydrogen. Hence they cannot be
solid oxide fuel cells may soon become a     significantly reduced by any amount of
viable cogeneration technology.With          research and development. We have to
modest fuel conditioning, these cells        accept that hydrogen is the lightest
convert fossil fuels directly with up to     element and its physical properties do
50% LHV electrical efficiency.       They    not suit the requirements of the energy
will    compete      with     conventional   market.      The production, packaging,
cogeneration equipment in a natural gas      storage, transfer and delivery of the gas
                                                                                  81

are so energy consuming that other           compression or liquefaction of the
solutions must be considered. We cannot      hydrogen, and transport by trucks would
afford to waste energy for uncertain         incur large energy losses.      However,
benefits; the market economy will            hydrogen solutions may be viable for
always seek practical solutions and, as      certain niche applications. For example,
energy becomes more expensive, select        in private buildings excess rooftop solar
the most energy-efficient of all options.    electricity may be used to generate
Judged by this criterion, a general          hydrogen, store it at low pressure in
"Hydrogen Economy" can never become          stationary tanks for cogeneration with
a reality, although hydrogen will            engines or fuel cells.    Or surplus wind
gradually become more important as           electricity may be stored as hydrogen for
energy transport and storage medium.         power generation during periods of calm.
This article provides some clues for the     As stated at the beginning, hydrogen
strengths and weaknesses of hydrogen as      generated by electrolysis may also be the
an energy carrier.         Certainly the     best link between physical energy from
proportion of energy lost depends on the     renewable sources and chemical energy.
application.     One can not deny that       But it is questionable if hydrogen in its
transporting hydrogen gas by pipeline        elemental form will ever become a
over thousands of kilometers is difficult.   dominating energy carrier.
Furthermore, one can not deny that


References:                                     2. R. Hammerschlag and P.Mazza,
                                                   Energy Policy, (Article in Press,
   1. R.S. Cherry, Int. J. Hydrogen                2004)
      Energy, 29 (2004) 125                     3. U. Bossel, Europen Fuel Cell
                                                   News, 10 (2) 2003.
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