eli5 – Why can’t planes take off/land using fuel but fly using solar power when in flight (daytime)

Question

Surely it would save some carbon emissions if the plane was clad in solar panels and could use solar energy once airborne/above the clouds?

In: 0

Answer 1

One gallon of gasoline is equivalent to 36 kilowatt hours. So it would take 360 of those 2 x 3 foot panels you see on your neighbors roof, in direct sun for an hour to provide the same energy as one gallon of gas. Now let’s say a small plane uses 10 gallons an hour. That’s 3,600 panels. All that’s assuming 100% efficiency.