Photovoltaics are way less powerful than you give them credit for, unless you want the electric motors to only push it at 10 knots... Where pv excels is cumulative kWh per month collection from something like a big cheap ground based array, the amount of watt hours you could collect in 12 hours from a top half of an airship covered in PV is not a lot, compared to the load of powerful electric motors.
I did the math for USS Akron, which was around 240x40m and was propelled by a 3.3MW power plant.
It has a projected surface area of 7500m2, which, using modern, 22% efficient monocrystalline panels, yields 1.65MW, or half the desired amount, which I assume was used mostly for liftoff.
In any case it's the same order of magnitude, so should be at least somewhat useful.
There's always the question of weight, but much of that is the usual glass and aluminium casing.
The devide your numbers in half because sun will only ever hit half the airship. Then realize that when you neee power the most, in bad weather, the sun wont be there. Then subtract the mass of all those panels from the availible payload.
From @Tade0 writing "projected surface area", they have already accounted for the fraction in sunlight. You can also tell this is what was meant by noting a rectangle of those dimensions is larger than the stated projected area, which you should expect from the pointy bits on the ends.
The weather that destroyed the USS Akron seems rather more important than the power source. I wonder if we can reliably make them go above or around clouds these days? I’ve not noticed clear air turbulence in air travel since I was a kid.
If you have a positive answer on the weather safety, and if the PV is light enough that it could be considered a way of reducing fuel use rather than a Boolean yes/no decision to either fully replace a chemical fuel or not use it at all, it seems worth investigating.
Edit: Just realised, while I’m usually unconvinced by RF beamed power, but with that surface area, and the general form of the inner frame, and it being in the sky so less danger from industrial accidents, this might possibly be a case where it could work.
