Heat-pump water heaters produce more than twice as much hot water per kilowatt-hour of electricity consumed as standard electric water heaters. Not only that, the by product from this heat is free air cooling. I think this type of water heater is a must in our Atlanta climate. In fact if you have a solar pv system, place this unit in the same room as the power inverter. Thus the heat put off from the inverter would be captured and used in your hot water. The cool air emitted from the water heater would chill the inverter and make it more efficient.