"Bob" wrote in message
Would it be economical to turn off the heater at night and back on in the
mornings. One thought says, "yes", but the other is that it would have to
reheat the water equal to the overnight lost temp, and wouldn't save
anything.

You may save a tiny bit. Water heaters are better insulated than they were
years ago.

Next question, do you heat your house? If so, any loss from the water
heater will go toward heating your house during heating season. It would be
wasted the rest of the year.

If you decide to do this, you need a timer to turn it back on well before
you need the water in the morning as it will take time to recover.