On this subject I heard a story, and I'm not sure if its an old wife's tale, involving, apparently, a quite famous football club (which I won't name)
The club refurbed its stadium and bought a state-of-the-art, several-thousand-pound generator to power the lights in the stadium and floodlights in the event of mains electrictity failure. It was also to be used as the stadiums source of power for emergency lighting too.
The Local Authority however said that the generator could not be used to power the emergency lighting as it wouldn't kick in quick enough in the mains failure
Having spent a serious wedge of cash on the generator the football club scratched their heads, and decided that on all match days it would power the primary lighting / floodlights by means of the generator, and said that their back up should the genie fail, would come courtesy of the mains electricty.
Apparently the local authority accepted it....
... anyone confirm or deny if that is a myth?