How to choose the most energy-efficient home heating system
You must understand how heating systems are rated by efficiency. AFUE (Annual Fuel Utilization Efficiency) is a measure of the percentage of energy use that actually goes into heating the home. For example, a furnace with an AFUE of 85 means that 85 cents of each dollar spent on energy goes to heating the home.
Heat pumps are rated by HSPF rather than AFUE, which represents total heat output. (SEER rating is used for heat pumps in cooling mode.)
The other thing you need to understand is what kind of system you need. This will vary widely depending on where you live, climate, and how your home is built. Ask an HVAC technician about which system is recommended for your home.
Differences Between Energy Efficient Heating Systems
Heat pumps are the most energy efficient heating systems around. They move air in and out of the home, using various methods to heat and cool the air in the home.
Air-source heat pumps use refrigerant to cool air when in cooling mode, and extract heat from air outside when in heating mode. As a result, these types of heat pumps do not work well in colder climates.
Geothermal heat pumps use the soil or a nearby body of water as a source of heat capture and heat release. These are much more efficient and stable than air-source heat pumps, and are the most energy efficient heating system around, cutting heating bills by up to 70 percent. However, the high cost of installation puts some homeowners off of it.
Furnaces are the most common heating system used in residential homes. They vary widely in efficiency, with older units being very inefficient and newer units being highly efficient. Furnaces can run on gas, oil, or electricity.
Gas furnaces are generally the cheapest to operate, despite not being as efficient as air-source heat pumps or electric furnaces.
To see how efficient a furnace is, check its AFUE rating. The higher, the better.
● A more modern heating system will generally be more efficient.
● Heat pump efficiency in heating is rated with a HSPF, and furnaces are rated with AFUE. The higher the rating, the more efficient it is.
● Geothermal heat pumps are the most efficient home heating system around. If you can afford the installation cost, they can lower your energy bills significantly.
● Gas furnaces, despite not being as efficient as many other types of home heating systems, are often cheaper to operate than air-source heat pumps and electric and oil furnaces.