I was used to this when living in the UK. Moved to the US, got the pool filtering 80% of the time at night, turned on the washing machine at night, after a year of this, wife asks why I do all this at night. "electricity is cheaper at night" "is it?" "of course...wait. maybe, lets ask your brother, he works for the power company" /askBrotherInLaw "hahahahha! No! we managed to get that killed quickly, some people tried it, and we can offer that if you /really/ want, but we stack it up so much, that you'll never make a return on the investment for all the equipment you need to plug in for a big building (and we don't offer it to regular consumers, only big office buildings that beg, so, yeah,not a chance. We've stacked it to cost you so much more than regular electricity rates"
!So... that's great.