Water heaters account for about 18% of the energy used in the home making them the second highest energy user in the average Wisconsin home. This makes choosing an energy efficient water heater for your home one of the most important decisions you will make as a homeowner.
Conventional (tank) water heaters use a large, insulated tank to store cold water. When the tank is full the water is heated using natural gas, electricity, or propane. The hot water is stored and kept warm until it is ready to use. The size of the tank determines how much hot water is available at once. Tank water heaters are the most common and have the lowest up-front cost of all types of water heater.
Tankless water heaters heat do not use a tank to store hot water. Instead, super-heated coils fill with water. The water is heated and delivered on-demand. This is a great option for heating water quickly. Properly sizing your system is an important thing to consider when shopping for a tankless water heater. As an undersized system would result in lukewarm water and an oversized system would result in energy waste. Tankless water heaters are more expensive than conventional and more difficult to install in existing homes. However, they can be up to 34% more efficient than their conventional counterparts.
Heat Pump Water Heaters
Heat pump hot water heaters pull heat from surrounding air instead of generating heat directly. The heat pulled from surrounding air is transferred, at a high temperature, to water that is stored in a tank. HPWHs are more expensive than conventional water heaters, but they can also cost less than half as much to operate. HPWH systems can be 2 to 3 times more energy efficient than conventional electric resistance water heaters. You can even install an air-source heat pump system that combines your HVAC and water heating.
Solar Water Heaters
Solar water heaters absorb heat energy from the sun using roof mounted solar collectors and transferring that heat to water stored in a tank at ground level.
Indirect Water Heaters
Indirect water heaters use your homes existing HVAC system (eg. Boiler or furnace) to heat water that is stored in a tank and distributed when needed.