flueless water heaters-pvc vented
In most areas an all electric water heater will cost somewhat more in operating costs than a natural gas heater including the power vented models (that use electricity). Power vented heaters make up for some of the electricity for the fan by stopping the flue air flow when the burner kicks off. The flue flow with the burner off always steals at least a little heat from the water since the flue flow goes up the middle of the tank.
The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.