The Tank › 50 Gallon Hybrid Electric or 80 Gallon Regular Electric? › Reply To: 50 Gallon Hybrid Electric or 80 Gallon Regular Electric?
Hello: Bigger heat pump units can be more efficient because they don’t need to use resistance elements to heat water as often. Heat pumps are slower in heating than heating elements, so they need bigger tanks to be able to handle the peak hot water use times, like morning showers. So, although it’s counter-intuitive, with a heat pump, a bigger tank is better. (With a normal electric heater, smaller is better.) I’d still look for something that allows you to maintain the heater, particularly giving you access to the sacrificial anode.
Understand these units can make some noise and they have air filters that MUST be cleaned regularly or performance suffers. If you have time of day metering, letting the heat pump run only during off-peak hours could reduce energy costs yet further. Consider demand pumping as well for getting hot water to the taps with minimal waste and waiting time.