Jed wrote: >>At this point I also need to ask, how much energy does the evolution >>of the excess hydrogen actually account for? As a percentage of the >>total energy in, do you happen to know if it's typically on the >>order of 1%? 10%? 50%? > > 8000% for brief periods. (80 times input.) For one overall run, > electrolysis alone would have produced 460 cc of hydrogen and 1470 cc > of gas was produced instead.
No Jed, energy efficiency and current (faradaic) efficiency are different things. Input power is voltage times current, but only exactly 1.48V out of the ~300V GDPE voltage is devoted to electrolysis (1.48V= dissociation energy of one H2O molecule divided by twice the electron charge), so electrolytic dissociation energy is only 1.48/300 ~ 0.5% of the input power. Therefore 80 times faradaic efficiency for brief periods means that 80*0.5%=40% of the input energy goes into H2O dissociation energy, not 8000%! And 3 times overfaradaicity for one overall run means that only 3*0.5%=1.5% of input energy is going into dissociation, that's why dissociation energy is usually ignored in the GDPE energy balance (1.5% << 30%). Do let me know if any of the above didn't make sense. Michel
