In article , Smitty Two wrote:

Here is the difference to which I refer: You save money on the home
heating issue because you're lowering your average home temperature. You
don't save money (of any appreciable amount) on the hot water tank,
because you aren't lowering your hot water temperature. All you're doing
is making up the heat loss in one big chunk in the morning, instead of
incrementally throughout the night.

I disagree. By shutting off the water heater at night you are also lowering
the average temperature of the water -- and the situations are the same.