A tankless water heater is much more efficient than a traditional water heater because it only heats the water that is being used instead of heating and reheating water stored in a tank. Rinnai, Rheem, and Bosch all make versions of tankless water heaters that are well-reviewed.
One of the most energy efficient water heating methods is the heat pump water heater. This method is proven to be two times more efficient over the standard electric water heater.
The most efficient heater for a water tank is a tankless water heater. It heats water on demand, only when needed, which can save energy compared to traditional water heaters that constantly heat and store water.
The most efficient electric water heater available on the market is the heat pump water heater, which uses electricity to move heat from the air or ground to heat water, making it more energy-efficient than traditional electric water heaters.
Any heater that has the Energy Star label will be very energy efficient. The Honeywell eco line, for instance, are very energy efficient.
The most efficient electric hot water heater available on the market is the heat pump water heater.
The question is better defined as "What the most energy efficient portable heater?" Because one would assume that you will want to be able to take the heater with you when or if you move.
Tankless water heaters are considered the most efficient hot water heaters on the market as they heat water on demand, eliminating the need for a storage tank and reducing energy waste.
A large energy saving one. It will keep lots of hot water and will use less energy when not in use.
instant gas
Tankless water heaters are considered the most efficient option on the market today. They heat water on demand, eliminating standby energy loss associated with traditional tank water heaters.
There is no single answer to this question. Water heaters with Energy Star certification are your best bet. However, the important considerations are what you need. If you get the right size, set the right temperature, and insulate your water heater, that will make more difference than the specific brand. The most energy efficient hot water heaters are tankless. Check your local Home Depot or Lowes for pricing and installation information.
Gas-fired, storage-based water pumps are the most energy efficient type.