I think, it will be interresting to have two differents cost per KWH for french people as my "abonnement" is a day/night cost.
So it will be interresting to had in location a day night option with hour variable for the going in night to day cost.
Perhaps it's better to had generics variables for example:
cost per kwh = "...." between "xxhxx" and "xxhxx" at "day1"
cost per kwh = "...." between "xxhxx" and "xxhxx" at "day2"
As is, everybody in the world may use those options.