The Rheem EcoSense 50 Gallon Hybrid is Rheem's most advanced energy efficient Electric water heater. EcoSense hybrid water heaters work much like a refrigerator in reverse. Utilizing heat pump technology, it uses the warm ambient air temperature to do most of the work. Easy to use LED touch pad helps you control the water temperature and offers 3 efficiency settings. Installs as easily as a standard electric water heater. Ideal for new construction and drop-in replacement in basements, garages, and attics.