A booming segment of the Perpetual Motion Machine industry is capitalizing on the hype over the "Hydrogen Economy" with claims to produce Hydrogen for impossibly low cost.


Errors in ARC's report to Xogen

The report lampooned in "Xogen and Faraday" purports to show that Xogen's Hydrogen generation process is not conventional electrolysis. It was prepared by ARC (the Alberta Research Council). The report is an odd hodgepodge. Extrapolations from electrolysis theory are made to 5 significant figures and defended with multiple footnotes. But the tests on the Xogen device are described in vague terms with important measurements not reported, and others reported to only 2 sig figs. A lot's been made of the fact that the report describes only the Amp-hours of current used in the Xogen tests, not the Voltage, making it impossible to determine the efficiency of the process. But that appears not to have been the purpose of the report. The report was, apparently, intended to show that Xogen's process isn't electrolysis. But why would anyone want to show only that the process isn't electrolysis, why not try to show that it's efficient? Maybe we'll never know. But what's clear is that the report shows the reverse of the conclusion, that the Xogen process is standard electrolysis. There were three errors in the Alberta Research Council's report that obscured the obvious truth from them:
  • The estimation of the amount of H2 to expect from electrolysis was done incorrectly;
  • No accounting of the impurities is shown for the measurement of the H2 from the Xogen process;
  • The circuit analysis is all wrong, undercounting the current for the Xogen process by a factor of 8.

  • I'll show the first two errors here and the third after Google finds me a more detailed version of the report.

    First lets look at how the results for electrolysis were calculated:
    1 mole of H2 gas is equivalent to 22.414 L, or 0.022414 m³ of H2 gas.
    2 moles of electrons are equivalent to 53.6 Ah [(2 mole)(96,485 C/mole)(1 A/Cs)(1 h/3600 s)].
    Ideally, 1.47 V is needed, so the ideal power efficiency is:
    (53.6 Ah)(1.47 V)/(0.022414 m³) = 3.52 kWh/m³ of H2 gas
    at 25 °C, 1 atm (1.013 bar).

    Simply put :
    53.6 Amp hours of current flowing will liberate 22.414 litres of hydrogen gas at 0 degrees C, 1 atm.

    The 22.414 litres from 53.6 Amp hours is then compared to the Xogen results. This is an extrapolation from theory, not an experimental result, and it's obvious why nobody would want to try to replicate it in the lab. Who would want to roll all that equipment into the freezer? How can you handle the instruments properly with mittens on? But since the Xogen process was, presumably, not tested in the freezer either, it's incorrect to compare to the volume at 0 degrees C. The MIT Ideal Gas Law calculator makes easy to check that at 70 degrees F, 53.6 Amp hours worth (one mole) of H2 is would be 24.145 l.

    Now about the impurities they say:
    (d) The output gas is a stoichiometric mixture of hydrogen and oxygen containing less than 3% water vapour;
    There would be other impurities as well as the air suspended in the water is going to be released as the water is heated, but water vapor would be the main one. But when the amount of H2 is calculated, the impurities do not seem to be taken into account. So where the ARC says:
    18 Amp hours of current flowing will liberate approximately 100.2 litres of hydrogen/oxygen gas of which 2/3rds (66.8 litres) is hydrogen and 1/3rd (33.4 litres) is oxygen.
    they should have shown that the impurities were not counted in the volume of H2 O2 mixture, but they don't. How much impurities were there? The ARC hinted at 3%. So where the ARC says there were 66.8 litres of H2 created, 64.8 is probably closer to the truth.

    Many people who read the ARC have computed:
    53.6 Amp hours for electrolysis / 22.414 l
    ------------------------------------------ = 8.9
    18 Amp hours for Xogen / 66.8 l

    which they round to 9.

    But it would be more correct to use:
    53.6 Amp hours for electrolysis / 24.145 l
    ------------------------------------------ = 8.0
    18 Amp hours for Xogen / 64.8 l

    So by my calculations, the Xogen process produces only 8 times as much H2 per unit charge as conventional electrolysis. Which is perfect, since I'll show later that the circuit analysis error by the ARC leads them to undercount the current used in the Xogen process by a factor of 8.


    Blogger john lichtenstein said...

    Xogen's webpage from 2001-JuneSupport for 3% contamination estimate I used. Here Xogen reports 10% contamination. The Alberta Research Council used 0%. This is Xogen’s prototype hydrogen generator. It is constructed of clear plastic so you can see the process and technology.

    The generator is filled with tap water with no chemical additives and consumes a moderate amount of power. It also provides hydrogen on demand in a self-pressurizing vessel.

    The gas output is approximately 60% hydrogen, 30% oxygen and 10% other, based on the impurities in the water. This gas mixture with the addition of air will run an internal combustion engine.

    The resulting exhaust is condensed water vapour with zero fuel emissions...

    July 20, 2004 1:29 PM

    Anonymous Anonymous said...

    I was watching Xogen's video, and I noted what striking similarities their process had with Stanley Meyer's processes, whose brother is working on a reduced version of his (dead) brother's hydrogen separation process, which is an inter mixture with gas instead of Stanley's use of water as a fuel in and of itself. Just noticed.


    December 11, 2006 7:44 AM

    Anonymous Anonymous said...

    When xogen said 18 Amp hour, that on what voltage? Is it 1,47Volts or may be 24 Volts?

    December 05, 2008 3:27 PM


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