Cheers- I guess I'll add, the turbofans that all modern airliners use are almost always referred to by their 'thrust' and you ofter see a lot of published numbers of takeoff thrust and such - it is harder to find numbers at cruising seed and altitude, and then in reality what you need to know is the actual power needed to generate that thrust.... there is some complexities there but in general the turbines generate what is known as 'shaft horsepower' which is a good stand in number we're looking for to compare.

The real takeaway is that power is power and energy is energy and regardless of how it gets to do the 'pushing' of the air, if you want to use solar energy (power, at any given moment, not integrating over time) those are the numbers you are comparing. It's all just unit conversions, at least when you're attempting such napkin math. Anything more - taking into account the actual systems, losses, efficiencies, etc.. just makes it all worse, not better.

A cool exercise is - given the 777 wingspan I esitmate and the power output from solar of said size... what kind of current aircraft use piston-driven engines with similar horsepower? Assuming we had motor inverter electronics and an electric motor that was 100% efficient, you could imagine trying to build a similar weight aircraft of that size that has such a wingspan.

This is why you wind up with the only solar powered aircraft out there being superlight, high altitude craft with super high aspect wing surfaces- maximizing wing area to weight / lift capability such as: https://en.wikipedia.org/wiki/AeroVironment_Helios_Prototype (note the largest of those prototypes and the tiny amount of power output they were making. All that wing area and it would have barely been able to carry a single passenger as payload and cruise a day without battery power)