He gauged his propane use by his monthly fillup gallonage during the summer months where the outside temperature was relatively steady and warm (so the tank fills were all to about 80 percent).
He didn't see ANY difference in propane use between these two scenarios. Control: 50 gallon hot water heater left always on Testing: He turns on the hot water heater each morning for an hour
Since it's just him, his wife, and one other adult, they can all take showers in the morning on that schedule.
Given that a new on demand system could cost as much as five grand, would you agree with him that on-demand systems have no economic value?