A variety of technologies are available for heating your home. Listed below are the most common heating technologies used.
- FURNACES – Furnaces are the most common way to heat a home; 65% of single-family homes in the United States have a central forced-air furnace that distributes heated air throughout the house via ducts. More than two-thirds of these are fueled by natural gas; other heat sources are electricity, oil, and propane.
- ELECTRIC HEATING – Not including heat pumps, 14% of single- family homes are heated with electric resistance heat; most are central forced-air electric furnaces, but many homes use electric space heating, either wall-mounted or baseboard, as their main heat source.
- HEAT PUMPS – 10% of U.S. homes use heat pumps. These systems can be air-source or ground-source, and are ducted or ductless.
- BOILERS – Boilers are used for heating in 8% of U.S. homes. Boilers use natural gas, oil, electricity, or propane to heat water for steam or hot water that is distributed via pipes to upright radiators, baseboard convectors, or radiant floor tubing. Combination units can provide space and water heating.
- WOOD AND PELLET-FUEL STOVES – These provide a way to heat your home using biomass or waste sources and are a primary heat source for 3.5% of single-family homes.
- SOLAR – Active solar heating uses the sun to heat air that is then ducted or blown into living space. Less than 0.4% of homes have active solar heating. Solar water heaters can preheat water for radiators or radiant floor heat.
Common Heating System Options
|Fuel Type||Installed Cost*||Ducts or No Ducts||Central or Room Heating||Best Climates||Minimum Federal Efficiency Requirement||Expected Efficiency of High- Performing Models||ENERGY STAR Version 3.0 Minimum Efficiency**||CEE Minimum Efficiency|
|Furnace||Natural Gas, Fuel Oil, Propane||Medium- High||Ducts||Central||Moderate- Cold||78% AFUE||90% – 98% AFUE|| Gas:|
80% AFUE CZ 1-3;
90% AFUE CZ 4-8
80% AFUE CZ 1-3;
85% AFUE CZ 4-8
| Tier 1: 90% AFUE |
Tier 2: 92% AFUE
Tier 3: 94% AFUE
|Electric Resistance||Electricity||Low||Either||Either||Warm- Hot||–||100%||NA|
|Air-Source Heat Pump||Electricity||Medium- High||Ducts||Central||Moderate- Warm||7.7 HSPF||10-12 HSPF, 200+%||8.2 HSPF CZ 1-3; 8.5 HSPF CZ 4; 9.25 HSPF CZ 5; 9.5 HSPF CZ 6***||Tier 1: 8.5 HSPF Tier 2:_> 8.5 HSPF|
|Ground- Source Heat Pump||Electricity||Very High||Ducts||Central||All||7.7 HSPF||2.3-5 COP, 300+%||ENERGY STAR Qualified Models||Closed-loop 3.3 COP; Open-loop 3.6 COP; Direct Expansion|
|Ductless Mini-split Heat Pump||Electricity||Medium- High||No Ducts||Room Heating||All||7.7 HSPF||10-12 HSPF||8.2 HSPF CZ 1-3; 8.5 HSPF CZ 4; 9.25 HSPF CZ 5; 9.5 HSPF CZ 6***||Tier 1: 8.5 HSPF Tier 2: 9.0 HSPF|
|Boiler||Natural Gas, Fuel Oil, Propane||High||No Ducts||Central||Cold||75% AFUE steam,|
80% AFUE hot water
|90%-95% AFUE||80% AFUE CZ 1-3; 85% AFUE CZ 4-8||Tier 1: 85% AFUE|
|Wood, Pellet||Wood, Pellet||Low- High||No ducts||Room Heating||All||Varies||72% to 90%||75%||–|
* Estimated typical installed cost ranges for retrofits. These estimates do not include adding or repairing distribution systems. Low: $2,000 or less, Medium: $2,000 – $4,500, High: $4,500 – $10,000, Very High: $10,000 or more (www.energysavers.gov).
**ENERGY STAR Version 3.0 criteria, which became effective 4/1/2011, are climate specific and are based on the U.S. climate zones (CZ) identified in the International Energy Conservation Code (IECC) 2009 as defined by the U.S. DOE Building Energy Codes Program (www.energycodes.gov).
***An 8.2 HSPF air-source heat pump will qualify for ENERGY STAR in Climate Zones 4 – 8 if it is combined with an ENERGY STAR-qualified dual- fuel backup furnace.