Which if you go that angle the capex on a heat pump heater regardless if hybrid or pure electric is going to negate any savings, those are typically 2-3x of a higher quality brand traditional water heater.
Which full circle going back to the original discussion of turning off the heater. You probably end up close to no/low savings. I can see an argument of a smart heater being able to slightly adjust load at peak times but I engineering a heater to turn off when you are sleeping and then heating back up before use is probably going to not have much savings. Those heaters are increasingly made to edge out at maintaining the heat and take quite a few hours to heat up.
Which full circle going back to the original discussion of turning off the heater. You probably end up close to no/low savings. I can see an argument of a smart heater being able to slightly adjust load at peak times but I engineering a heater to turn off when you are sleeping and then heating back up before use is probably going to not have much savings. Those heaters are increasingly made to edge out at maintaining the heat and take quite a few hours to heat up.