Acura Engineering

A. O. Smith heat pump water heaters are designed to be energy efficient and cost effective alternatives to traditional water heaters. They can quickly heat large amounts of water and can have storage capacities of over 450 liters. A. O. Smith heat pumps work by using a fan to pull air from the surrounding space into an evaporator, where refrigerant absorbs heat from the air. The refrigerant then passes through a compressor, which increases its temperature and pressure. 
Some A. O. Smith heat pump water heaters include:

HPA 120 Split Type Heat Pump Water Geyser

This water heater is designed to provide efficient water heating and a good bathing experience.

Commercial CAHP 80-06 Heat Pump Water Geyser
This water heater has smart controls to prevent cold water from mixing in, and is designed to provide a premium bathing experience.