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Hydrogen Economy & Ozone Layer Debate

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  • Mike Neuman
    From: Twenty Hydrogen Myths published at www.rmi.com, by Rocky Mountain Institute. Free online at www.rmi.org. His report was updated on 12 July 2003. Myth
    Message 1 of 3 , Sep 25, 2003
      From: "Twenty Hydrogen Myths" published at www.rmi.com, by Rocky
      Mountain Institute. Free online at www.rmi.org. His report was
      updated on 12 July 2003.


      Myth #14. A large scale hydrogen economy would harm the Earth's
      climate, water balance, or atmospheric chemistry. Sub. d. Using
      hydrogen would harm the ozone layer or the climate by leaking too much
      water-forming and chemically reactive molecular hydrogen into the
      upper atmosphere.

      This is incorrect because:
      They grossly overstated the hydrogen leak rates: instead of their
      assumed 10-20%, a more plausible estimate is at worst 1-2 percent,
      more likely a few tenths of a percent of less. (152- E.g., the current
      German industrial hydrogen system's 0.1% leak rate plus a bit more for
      retail distribution and some special but minor losses associated with
      fueling and operating fuel-cell vehicles. Prospective leak rates for
      entire hydrogen systems are being carefully assessed by Dr. Mark
      Delucchi at the University of California/Davis.)

      The authors do agree that hydrogen "emissions could be limited or made
      negligible, though at some cost," and no doubt the furore over their
      paper will help to focus attention on this issue, but they seem
      unaware that the hydrogen industry already achieves extremely low
      leakage as part of its normal operating practice and at modest cost,
      simply as a prudent strategy for public and asset protection.

      They didn't credit hydrogen for its greater end-use efficiency,
      enabling less hydrogen to deliver more service than can the fossil
      fuels it displaces.

      They didn't credit a hydrogen economy for reducing or eliminating most
      of the present causes of hydrogen emissions, which originate in fossil
      fuel and biomass usage. (Direct use of renewable energy without going
      through hydrogen would of course displace fossil fuels without any
      hydrogen leaks.)

      Altogether, these factors would make a soundly designed hydrogen
      economy reduce current releases of hydrogen by one or perhaps two
      orders of magnitude, to a level well below natural hydrogen releases.
      (153. A.B. Lovins, letter submitted 17 June 2003 to Science, to be
      posted at www.rmi.org.
    • Richard Risemberg
      The hydrogen economy, and you don t have to read too deeply into matters to discern thsi, is a desperate attempt to keep all the cars we have now on the road
      Message 2 of 3 , Sep 25, 2003
        The "hydrogen economy," and you don't have to read too deeply into
        matters to discern thsi, is a desperate attempt to keep all the cars we
        have now on the road and clogging the Earth's surface and our cities for
        as long as possible. That's what it really is.

        Richard

        Mike Neuman wrote:

        > From: "Twenty Hydrogen Myths" published at www.rmi.com, by Rocky
        > Mountain Institute. Free online at www.rmi.org. His report was
        > updated on 12 July 2003.
        >
        >
        > Myth #14. A large scale hydrogen economy would harm the Earth's
        > climate, water balance, or atmospheric chemistry. Sub. d. Using
        > hydrogen would harm the ozone layer or the climate by leaking too much
        > water-forming and chemically reactive molecular hydrogen into the
        > upper atmosphere.
        >
        --
        Richard Risemberg
        http://www.living-room.org
        http://www.newcolonist.com

        "I believe that every right implies a responsibility; every opportunity,
        an obligation; every possession, a duty."
        John D. Rockefeller, Jr.
      • Mike Harrington
        It is doubtful that fuel cells will ever replace internal combustion. The technical article below quantifies the huge cost of hydrogen fuel. The hydrogen
        Message 3 of 3 , Sep 25, 2003
          It is doubtful that fuel cells will ever replace internal combustion. The
          technical article below quantifies the huge cost of hydrogen fuel. The
          hydrogen economy is a mirage.

          ----- Original Message -----
          From: "Richard Risemberg" <rickrise@...>


          > The "hydrogen economy," and you don't have to read too deeply into
          > matters to discern thsi, is a desperate attempt to keep all the cars we
          > have now on the road and clogging the Earth's surface and our cities for
          > as long as possible. That's what it really is.
          >
          > Richard
          >

          You might find useful parts of this recent letter to the editor of
          Chemical and Engineering News (August 25, 2003
          Volume 81, Number 34) concerning hydrogen fuel cell
          technology.

          John Magner
          The Woodlands, Texas

          Our nation's real need for a viable long-term solution to
          renewable energy, especially for private transportation, is not
          well served by articles that paint a fanciful picture of the promise
          of fuel cells (C&EN, June 9, page 35; June 16, page 16).
          Economically viable solutions for the following fuel-cell
          challenges seem highly unlikely in the foreseeable future.

          The total cost (without subsidy) of proton exchange membrane
          (PEM) fuel-cell engines (fuel cells, power conditioning, electric
          motors, and so on) with mass low enough to be practical in a
          vehicle is in the range of $3,000-$7,000 per kW--40 times that of
          the advanced diesel engine. It is worth noting that PEM fuel cells
          have been in use and development for 40 years, and costs have
          not yet begun to drop significantly--notwithstanding many
          assertions to the contrary (such as those in the June 16 article)
          that use artificial costs from heavily subsidized projects or cite
          costs of massive, stationary fuel cells that are unsuitable for
          vehicles.

          Safety-approved affordable compressed-gas cylinders achieve
          1.5% H2 storage by mass at 34 MPa (5,000 psi). A $25,000
          carbon-fiber-wrapped fuel tank achieving 6% H2 storage seems
          impractical for the small private car, and liquid hydrogen (LH2)
          doesn't keep long. The huge mass penalty associated with
          economical H2 storage seems likely to keep the mileage of
          fuel-cell-powered automobiles (of acceptable range,
          acceleration, cost, and cargo capacity) below 25 miles per kg of
          H2 for many decades.

          Current U.S. H2 production is enormous--about 2 x 1010 kg per
          year. Yet the current pretax cost of LH2, delivered in 15,000-gal
          (4,300-kg) tankers to high-volume customers, is $4.30 per kg,
          and other methods of H2 distribution are even more expensive.
          On the other hand, the current U.S. pretax cost of gasoline for the
          individual consumer at the local station is about 30 cents per kg.

          The only economically viable sources of H2 in the U.S. are
          natural gas and coal. The nearly adiabatic
          partial-oxidation/reformation/shift reactions use 3 kg of natural
          gas (90% CH4) to produce 1 kg of H2 plus 9.5 kg of CO2. Then
          more than 3 kg of coal must be burned (releasing another 10 kg
          of CO2) to generate the 10 kWh (36 MJ) needed to purify and
          liquefy 1 kg of H2. The energy efficiency in producing LH2 is
          under 50%. (This number has not budged in 15 years and will
          not in the next 50. We're near Carnot limits.) The energy content
          of 1 kg of H2 is equivalent to 2.8 kg (1.1 gal) of gasoline, which
          contains only 2.3 kg of carbon.

          At 80 miles per gallon, the advanced diesel hybrid achieves 7
          miles per kg of total CO2. The fuel-cell automobile at 25 miles
          per kg of hydrogen achieves 1.1-1.3 miles per kg of total CO2.
          Hence, when miles per kg of CO2 release ("fossil mileage") is
          more fairly calculated, the total CO2 generated per mile by a
          hydrogen vehicle is likely to be five times that of a comparable
          diesel-powered hybrid vehicle for at least four decades. (If we
          have not been able to raise fuel taxes a nickel in the past two
          decades, how can we expect to impose a $1.00 per kg surtax on
          H2 production to support CO2 sequestration?)

          It is most interesting to note that, seven years ago, the
          Department of Energy expected fleets of fuel-cell-powered
          vehicles to be in use by now. Today, they are projecting that will
          occur seven years from now. Undoubtedly, if DOE invests $2
          billion (as expected) over the next seven years, many more
          demonstration vehicles (at $300,000 each) will be on the road,
          but that really does not accomplish much. I expect to still see that
          "seven-year" projection for commercial fleets 20 years from now.
          It's time we start putting some serious money into real options
          for our future transportation needs.

          F. David Doty
          Columbia, S.C.
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