Where could I go to find a realistic efficiency of a hydrogen fuel cell, and of electrolysis? I want to find out how much energy would be lost if I were to use electrolysis to fuel a hydrogen fuel cell, assuming that I was feeding the electricity from the fuel cell back into the electrolysis. I've found this site: Electrolysis of Water and Fuel Cell Operation
but it seems like it only details theoretically perfect fuel cells, rather than real world energy losses.
According to the link you provided, the efficiency is almost 83%. But Wikipedia claims entirely differently. See the link below to see what the efficiency is like.
