My napkin says you have 8C on the left and 9C on the right, so your stoichiometry is off. I haven’t tried to check any of the rest.
I’m guessing the major error is that the -0.8V is “versus reversible hydrogen electrode ”, so it’s a half-reaction and you need to fill in the correct other half reaction, and there is probably H2 involved. Then you would dig out some free energy values to see how efficient it is.
Gives a specific CO2 emission for propane of 13.8 kg carbon / kWh fuel, so your numbers are at least vaguely credible. But your reaction is devoid of CO2, so talking about tons of CO2 is still odd.
I’m guessing the major error is that the -0.8V is “versus reversible hydrogen electrode ”, so it’s a half-reaction and you need to fill in the correct other half reaction, and there is probably H2 involved. Then you would dig out some free energy values to see how efficient it is.
(I only read the abstract.)