| A hydrogen economy is proposed to solve
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| | by weight. The fuel cell is also more
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| the ill effects of using hydrocarbon
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| | efficient than an internal combustion
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| fuels in transportation, and other
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| | engine. The internal combustion engine is
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| end-use applications where the carbon is
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| | said to be 20-30% efficient, while the
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| released to the atmosphere.
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| | fuel cell is 75-80% efficient (not
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| Petroleum, which accounts for most of the
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| | accounting for losses in the actual
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| hydrocarbons imported by industrialized
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| | production of hydrogen) and together with
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| countries, is refined into gasoline and
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| | the electric motor and controller, the
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| diesel fuels to be used in automobiles,
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| | drive train overall efficiency approaches
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| aircraft and heating. Natural gas,
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| | 40% with low idling losses.
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| another hydrocarbon fuel, and coal are
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| | Hydrogen market
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| burned for the generation of electricity.
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| | TimelineHydrogen production is a large
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| The burning of hydrocarbon fuels causes
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| | and growing industry. Globally, some 50
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| the emission of greenhouse gases and
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| | million metric tons of hydrogen, equal to
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| other pollutants. Furthermore, the supply
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| | about 170 million tons of oil equivalent,
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| of hydrocarbon resources in the world is
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| | were produced in 2004. The growth rate is
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| limited, and the demand for hydrocarbon
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| | around 10% per year. Within the United
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| fuels is increasing, particularly in
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| | States, 2004 production was about 11
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| China, India and other developing
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| | million metric tons (MMT), an average
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| countries.
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| | power flow of 48 gigawatts. (For
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| In a hydrogen economy, once sufficient
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| | comparison, the average electric
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| renewable energy is available (a separate
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| | production in 2003 was some 442
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| problem which a hydrogen economy per se
| |
| | gigawatts.) As of 2005, the economic
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| does not address or solve), hydrogen fuel
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| | value of all hydrogen produced worldwide
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| would be manufactured from both fossil
| |
| | is about $135 billion per year.
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| and renewable energy sources and
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| | There are two primary uses for hydrogen
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| feedstocks, replacing gasoline, kerosene,
| |
| | today. About half is used to produce
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| and diesel fuel for transportation. Any
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| | ammonia (NH3) via the Haber process,
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| carbon-containing energy sources (methane
| |
| | which is then used directly or indirectly
|
| and fossil fuels) used in the manufacture
| |
| | as fertilizer. Because both the world
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| of the hydrogen would be sequestered on
| |
| | population and the intensive agriculture
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| site (carbon capture). The end use of the
| |
| | used to support it are growing, ammonia
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| hydrogen would be direct combustion in
| |
| | demand is growing. The other half of
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| heat engines, or as fuel in proton
| |
| | current hydrogen production is used to
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| exchange membrane fuel cells. Both
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| | convert heavy petroleum sources into
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| processes would only produce one
| |
| | lighter fractions suitable for use as
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| greenhouse gas: water vapor.
| |
| | fuels. This latter process is known as
|
| Secondary rationale
| |
| | hydrocracking. Hydrocracking represents
|
| Grid load balancing of electricity is a
| |
| | an even larger growth area, since rising
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| major issue in energy supply. Currently,
| |
| | oil prices encourage oil companies to
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| this is done by varying the output of
| |
| | extract poorer source material, such as
|
| electrical generators. However,
| |
| | tar sands and oil shale. The scale
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| electricity is difficult to store
| |
| | economies inherent in large-scale oil
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| efficiently for future use. The most
| |
| | refining and fertilizer manufacture make
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| cost-efficient and widespread system for
| |
| | possible on-site production and "captive"
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| large-scale grid energy storage is pumped
| |
| | use. Smaller quantities of "merchant"
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| storage, that is, pumping water up to a
| |
| | hydrogen are manufactured and delivered
|
| dam reservoir and generating electricity
| |
| | to end users as well.
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| on demand from that via hydropower.
| |
| | If energy for hydrogen production were
|
| However, such systems do not scale down
| |
| | available (from wind, solar or nuclear
|
| to portable applications. Smaller storage
| |
| | power), use of the substance for
|
| alternatives such as capacitors have very
| |
| | hydrocarbon synfuel production could
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| low energy density. Batteries have
| |
| | expand captive use of hydrogen by a
|
| relatively low energy density and are
| |
| | factor of 5 to 10. Present U.S. use of
|
| slow to charge and discharge. Flywheel
| |
| | hydrogen for hydrocracking is roughly 4
|
| power storage can be more efficient than
| |
| | million metric tons per year (MMT/yr). It
|
| batteries with about the same size, but
| |
| | is estimated that 37.7 MMT/yr of hydrogen
|
| there are safety concerns due to
| |
| | would be sufficient to convert enough
|
| explosive shattering.
| |
| | domestic coal to liquid fuels to end U.S.
|
| In a hydrogen economy, it is possible
| |
| | dependence on foreign oil importation
|
| that fuel cells, using hydrogen as a
| |
| | [1], and less than half this figure to
|
| fuel, will be able to replace most
| |
| | end dependence on Middle East oil. Coal
|
| internal combustion engines and at the
| |
| | liquification would present exactly the
|
| same time will solve most grid load
| |
| | same greenhouse problems as burning
|
| balancing needs. It will do this by
| |
| | foreign oil, but it would eliminate the
|
| allowing "storage" of electrical energy
| |
| | political and economic vulnerabilities
|
| in a grid of plug-in automobiles, which
| |
| | inherent in oil importation.
|
| will be available to store excess energy
| |
| | Currently, global hydrogen production is
|
| as hydrogen, and offering it to the
| |
| | 48% from natural gas, 30% from oil, and
|
| electrical grid as needed, after
| |
| | 18% from coal; water electrolysis
|
| conversion in fuel cells. Hydrogen in
| |
| | accounts for only 4%
|
| this sense would act like a chemical
| |
| | The large market and sharply rising
|
| battery and would essentially replace
| |
| | prices have also stimulated great
|
| battery technology in electrical hybrid
| |
| | interest in alternate, cheaper means of
|
| cars.
| |
| | hydrogen production.
|
| Hydrogen has an excellent energy density
| |
| |
|
