The energy content of the max fuel load of a 747 is something like 2.5 gWh. The specifics of the site matter an awful in how fast that pays back. So like if th

The energy content of the max fuel load of a 747 is something like 2.5 gWh. The specifics of the site matter an awful in how fast that pays back. So like if the extra generation were 1 megawatt with a capacity factor of 30%, you are looking at 7500 hours, less than a year, to yield that much energy. That's a lot of assumptions, but the delivery flights probably average less fuel than that, and one of the benefits of size is that the capacity factor goes up.