Comment by myrmidon

You don't just need to cover the 350km² with drones though, you also need buffering and/or transmission capabilities for absurdly high amounts of power (=> but low amounts of energy).

If you wanted a single buffer for the whole 350km², you'd need transmission capability from any point (or any drone launch station) to your central buffer in the Terawatt range (currently our highest power grid links are in the ~10GW range, so this is pure fantasy already). Utilization (~ capacity factor) for the lighting capture infrastructure would also be abysmally low. You'd basically need to build a ~10TW (generous estimate!) system, where costs in a lot of components directly scale with power, just to get ~10MW of sustained power out.

There is no way you are ever gonna compete with that $100M wind turbine; you could literally have cheap, high-field, room temperature superconductors and be gifted several warehouses worth of supercapacitors, and the whole lighning capture boondoggle still would not make any economic sense.