Better re-price that burger. If we spend about $12k to get that 10kwh battery (Pipistrel's price) and we get 500 cycles out of it (midrange of Pipistrel's 300-700 cycle estimate), the battery depletion cost for each trip is $24. Maybe you'll get more cycles at this low C rate, we can only hope.We can also calculate when an airplane with the efficiency of Archaeopteryx has a 4 hour autonomy. Since it is basically capable of flying at max FAR103 speed this represents the limits of usefulness for an out and back flight distance of 2 hours each way without recharge and about 110 miles distance without using altitude and winds at differing altitudes to affect the trip.
It is probably right about 10kwh of battery. The minimal 12.00 Hamburger machine. (10 dollar hamburger with 2 dollars of electricity at 20 cents a kwh)
Or, just burn 1 gal of gasoline ($3) for the same amount of mechanical energy at the prop.