Playing a high-energy-drain map where the fleet contained a number of reactor modules, the power drain bar for outstripped the usage bar (by 20 or more, 180 drain over 160 generation) while the global storage remained full.
It took some time to realise what had caused this. I don't know which drain measurement algorithm was eventually used, but how difficult would it be to adapt it to turn part of the usage bar green, to represent the power supplied by internal means?