How Green was GFC Electricity?

Dean Sigler Diesel Powerplants, Electric Powerplants, GFC, Sustainable Aviation 2 Comments

The blog received several comments about the relative energy use of electric aircraft, and how NASA and the CAFE Foundation might have overstated the efficiency and low emissions for the electric aircraft in the competition. Reader Robert Swanson thought the conversion between kilowatt hours and gasoline created a discrepancy. “The discrepancy in performance of gasoline and electric powered aircraft is due to an absurd conversion factor between kWh and gallons of gasoline.  The conversion should be calculated from the number of gallons of gasoline consumed by the engine driving the generator used to charge the batteries.” Steven Crow added this objection.  “Even after reading the relevant pdf’s, it is far from clear to me how CAFE computed ‘mileage’ for the electric aircraft. The right way of doing it is clear enough: base the mileage on the fossil fuel used to charge the batteries.  Electric motors and batteries are not subject to Carnot efficiency limitations.  They can seem to be nearly …