$5 does not make sense, and there must be some qualifer on that we're missing.

Napkin math:

(27 minute flight) * (25000 lbm TOGW) * (Earth gravity) / (~10 average L/D) * (160 KTAS average) / (70% propulsive efficiency) / (97% coulombic efficiency) * ($50/MWh) = $30

(Add residual kinetic energy upon landing too)

Side note: Heart also has a weight issue here they'll need to overcome if they want to certify under FAR Part 23 (as their 19-pax spec implies); TOGW limit for that is 19,000 lbm.

They’re using wholesale prices. The entire flight was 27 minutes, peaked at a megawatt of power, and a wholesale megawatt-hour is $40-50 these days.

I tried to run a napkin calculation, and that 5$ figure must be quoted per seat (30 seats). And a 'first flight' might be very very short, like 15 minutes of flying or less.

During certain hours of the day in California, electricity is essentially free due to solar overproduction, which sometimes causes negative wholesale prices.