11. The latest in water heaters an electric heat pump water heater A compressor and evaporator is integrated into the water heater. The evaporator draws in ambient heat from the surrounding air using two variable speed fans. Electric coils wrap the tank all the way to the bottom to transfer this heat into the tank and heat the water. An electronic back-lit LCD display at eye level lets you adjust temperature settings easily. Powered by PV panels Reduces water heating operating cost up to 62% saving up to $320 per year