When Doon gets his first glimpse of the generator, the camera views it from our perspective instead. Director Gil Kenan did it this way because Doon acts as our eyes and it conveys to us the importance of the generator to his city and our story.
There were so many sets built for the film that some of them wound up never being used. They do sometimes feature prominently in the background, like the hairdressers, but they play no part in the story.
The book sequel has been optioned, but considering the poor box-office reception of City of Ember (2008), it remains to be seen if it will be made into a film too.
A former paint hall in the shipyard of Harland and Wolff in Belfast's Titanic Quarter was converted into the city of Ember.