Hydrogen production through reforming methane at high temperature and pressure isn't efficient. That's a given. A side benefit of otherwise lost heat in carbonate fuel cells. Diesel never entered the picture.
As for hydrogen production and use in a solid oxide cell stack, your numbers are way, way off. Here' a link to a German paper from quite a few years back.
elib.dlr.de
Why would H2 from solid oxide stack electrolytic cell generation need any compression? Only a few bars pressure are necessary, if its not being hauled like PLUG plans to do. You use "MJ" figures from where? FCEL claims its solid oxide electrolysis is more than 90% efficient. Besides, storage of H2 for capture of wind and solar farm excess doesn't need to be compressed if used in close-by solid oxide cells for inversion into AC for transformation to transmission levels.
And, your numbers for windmill energy output don't make a lot of sense. Try a typical GE machine at roughly 1MW with the actual energy in Joules determined by how long the machine turns???? One hour at that rated output is 3600MJ, at least when a J is defined as a Watt-second.
Yes, when windmills turn, the maintenance clock turns. And, capacitors inside inverters may occasionally have dielectric issues. Something in common with battery stacks there.
The cost of unneeded wind capacity is ZERO, less maintenance. Why? It's lost otherwise. Same goes for central solar farms that aren't needed and if used would require scramming base load fossil or nuclear. Time and money lost in shut down and restart when the wind isn't blowing or after sunset.
But, when battery cells are charged and discharged, chemicals are lost, plates and canisters get consumed. There are a finite number of cycles before replacement. Then, there are the equal charge and discharge constraints. Stacking hundreds of 4 volt cells in series parallel can yield a "runaway" cell and catastrophic shorting and explosive consequences with little difficulty and with only a slight perturbation. Hint: Watch out for fender benders.... One blows and takes another dozen, three dozen or a hundred with it. Ever seen an electric car fire? Quite spectacular and hard to extinguish burning lithium chemistries. Quite a "wrench in the works." At least good old lead acid primary batteries don't do that.
Don't get lost in old cost data, like my neighbor does as a retired industrial gas engineering manager who reminds me of what you said about the immense cost and inefficiency of reforming methane with high pressure, superheated steam. No, not talking here about those costs being competitive or even relevant.
Green H2 can be viewed as something gained that would otherwise be lost. Just think. If Texas had hundreds of MW of fuel cell stacks and low pressure H2 hanging around from renewable generation of manufacture from solid oxide cells, the lights wouldn't have gone out as they did a month ago.
Nuf said. Thinking like they taught me. |
