I agree with Thoul in that I don't think the domes would be THAT big. They did have to be built on Palm, after all; I'm thinking maybe the size of a smallish country, tops. I know it's one of the great debates in games like these about how much time *really* passes, but let's face it - even at early levels, you can walk halfway across a dome without having to heal that much. Whatever method you use to determine time/distance, I don't think that each dome could be the size of an entire planet.
The regression from the high-tech sci-fi atmosphere of PSII to the medieval world (but with androids and spaceships?) of PSIII does raise some questions. Regardless of which timeline you're following (English or Japanese), war does break out eventually (either right after they leave Palma or one thousand years later). War depletes resources, and as they're on a spaceship, they probably had a finite amount to begin with. The name "Devastation War" implies that there was a whole lot of destruction going on, and even without it, the original refugees weren't going to live forever. Survival would have been the top priority and they probably would have wanted to find a way to get by with as little as possible.
A renewable resource to power the ship and keep everyone alive makes the most sense. Whatever's out there in space, someone else can answer, I'm not a science-y type.
