It also seems like if you simply leave it on a higher temperature 24/7 it will use more power due to thermal losses overall. This is a great hack for households with several people who like to take long showers (and thus run out of hot water), though, or if you can do some sort of variable temperature setpoint to store energy as described in the thread, though I think at least in the US electric tank-based hot water heaters are relatively uncommon.