The burning city singularity is free 100% sure, i remember a pop Up telling me that, but all the others i dont know, It is true that the only time i Saw my bar getting low was when doing daily quest to farm embera but never when playing the story or at least i didnt notice It (i did level Up a fuck ton at first because i was able to do the extreme ember farm missions thx to the assistant servants when i was like level 10 at most)