There is, but I dont know how the 787 electrical system works... I know its a full electric airplane with no bleed air so the electrical system is pretty stout I would think.
When I flew the 747 there was no checklist for loss of all A/C power i.e. losing all 4 generators at the same time. Boeing says its basically impossible. I heard of one where the E&E bay got soaked with water somehow and they lost all 4 generators due to a short from the water. The other couple are 4 engine flame outs due to volcanic ash. Another was supposedly mechanics blocked the generator cooling inlets while they were washing the engines and forgot to uncover them and all 4 generators over heated... 787 has liquid cooled generators I believe.
But to lose all 4 generators at the same time is a statistical improbability... I wont say impossible because, well...ill be proven wrong. The electrical system on the 787 SHOULD be designed so it doesnt have a single fault failure mode.
In 19 years in the airlines I have never lost a generator. I had a CSD drive light come on at idle power before on the 737, but the generator itself was still functioning. Low oil pressure in the CSD.
It could be possible there was 1 VSFG already on MEL, the other engine craps out (loosing both VSFGs) and then the other one on the first engine dies, having then lost all 4. However the VSFGs don't fail that often.
Now if it was CACs we were talking about, well that's a different story. But that's pressurization/aircon.
The 787 has a very very complicated electrical system, where there is multiple areas of failure possible.
While the systems aren't super reliable (components do get replaced fairly regularly) there is more than enough redundancy in the system.
