How we use energy in homes
The ability to heat and cool is one important accomplishment of modern technology. Our ovens, freezers, and homes can be kept at any temperature we choose, a luxury that wasn't possible 100 years ago. But keeping our homes comfortable uses a lot of energy.
Lighting is essential to a modern society. Lights have revolutionized the way we live, work, and play. Many homes have the traditional incandescent bulbs that were first invented by Thomas Edison. These bulbs convert only about 10% of the electricity they use into light; the other 90% is converted into heat. Today, more efficient light bulbs are available for most home energy lighting uses—halogen incandescents, compact fluorescent light bulbs (CFLs), and light-emitting diode bulbs (LEDs). These bulbs last much longer and use much less energy than incandescent bulbs, which results in significant savings over the life of the bulbs.
Light bulbs, heating and cooling equipment, refrigerators, washing machines, clothes dryers, and many other appliances and electrical devices are more energy efficient than they used to be, mainly because of minimum energy-efficiency standards established by the U.S. Congress in the Energy Policy and Conservation Act of 1978 and in subsequent amendments and laws. Learn what it means to be energy efficient.
More than half of energy use in homes is for heating and air conditioning
U.S. households need energy to power numerous home devices and equipment, but on average, more than half (51% in 2015) of a household’s annual energy consumption is for just two energy end uses: space heating and air conditioning. These mostly seasonal and energy-intensive uses vary significantly by geographic location, home size and structure, and equipment and fuels used.
Water heating, lighting, and refrigeration are near-universal and year-round home energy uses. In 2015, these three end uses combined accounted for 27% of total annual home energy use. The remaining share—21%—of home energy use was for devices such as televisions, cooking appliances, clothes washers, and clothes dryers, as well as a growing list of consumer electronics including computers, tablets, smartphones, video game consoles, and internet streaming devices.
Many factors affect the amount of energy a household uses
A number of factors affect the amount of energy an individual household uses, including:
- Geographic location and climate
- Type of home and its physical characteristics
- Number, type, and efficiency of energy-consuming devices in the home and the amount of time they are used
- Number of household members
Because of higher space-heating demand, households in the Northeast and Midwest regions of the United States consume more energy on average than households in the South and West regions. Larger homes and larger households tend to use more energy overall than smaller homes and smaller households.
Space heating and air conditioning account for a much smaller share of household energy use in apartments than in detached single-family homes. Apartments are generally smaller than single-family homes, and they are often partially insulated from weather by adjacent apartments. In 2015, the average household living in a single-family detached home consumed nearly three times more energy than a household living in an apartment building that has five or more apartments.
Did You Know?
In 1980, 56% of U.S. home energy use went to space heating. In 2015, the share was 43%.
Electricity and natural gas are the most-used energy sources in homes
Electricity is used in almost all homes, and retail electricity purchases accounted for 43% of total residential sector end-use energy consumption in 2020. Natural gas, which was used in 58% of homes in 2015, accounted for 42% of residential sector end-use energy consumption in 2020. Petroleum was the next most-consumed energy source in the residential sector in 2020, accounting for 8% of total residential sector energy end use. Petroleum includes heating oil, kerosene, and liquefied petroleum gas (LPG), which is mostly propane. Renewable energy sources—geothermal energy, solar energy, and wood fuels—accounted for about 7% of residential sector energy end use in 2020.
Overall, three-quarters of U.S. homes use two or more energy sources, but mobile homes in all regions of the country and homes in the South are most likely to only use electricity to meet all of their household energy needs. Heating oil use is most common in the Northeast. LPG use for grilling food outdoors is common throughout the country, while many homes in rural areas use LPG to meet the majority of heating and cooking needs. Wood is used as a main heating fuel mostly in rural areas but many homes throughout the country use it for supplemental heating. Approximately 11% of all U.S. homes in 2015 had geothermal heat pump heating and cooling systems. The number of homes with small-scale solar photovoltaic systems has increased substantially in recent years.
Energy use per household has declined
The typical U.S. household now uses more air conditioning, appliances, and consumer electronics than ever before. However, average annual site energy use per home has declined. The reasons for this decline include:
- Improvements in building insulation and materials
- Improved efficiencies of heating and cooling equipment, water heaters, refrigerators, lighting, and appliances
- People moving to regions with lower heating—and thus lower total energy—demand
The decline in average household site energy consumption has offset the increase in the number of homes overall, resulting in relatively flat residential sector energy consumption since the mid-1990s.
Electricity use in homes
Electricity consumption in U.S. homes varies by region and type of home
The average U.S. household consumes about 11,000 kilowatthours (kWh) per year.1 However, electricity use in homes varies across regions of the United States and across housing types. On average, apartments in the Northeast consume the least amount of electricity annually, while single-family detached homes in the South consume the most. Homes in the South are more likely to have electric heating and use more air conditioning.
Unlike natural gas, petroleum fuels, and wood, which are needed for only a handful of uses such as heating and cooking, electricity can power those and well over 100 other energy end uses for households.
- The three largest categories and their shares of residential electricity consumption in 2015 were:
- air conditioning17%
- space heating15%
- water heating14%
Lighting and refrigerators are used in nearly every home, and they are the next largest electricity end uses. The shares of annual electricity end uses can change from year to year based on the weather.
Air conditioning use is now common in most homes
Because of both population shifts to warmer climates and the availability of air conditioning in almost all new homes, air conditioning has been one of the fastest growing energy uses in homes. In 2015, about 87% of homes used air conditioning compared to 57% of homes using air conditioning in 1980. The percentage of homes with central air conditioning has more than doubled since 1980 when 27% of homes had central air conditioning systems compared to 64% in 2015.
Did you know?
The share of U.S. homes with central air-conditioning systems inceased from 27% of homes in 1980 to 64% in 2015.
Most homes have refrigerators and many have more than one
Nearly all homes—99%—have a refrigerator, and 30% have two or more. Second refrigerators and separate freezers are most common in Midwest homes, where, in 2015, 34% of homes had a second refrigerator and 39% had a separate freezer compared with 30% and 32%, respectively, for all U.S. homes. The most-used refrigerator in a home costs $81 per year to operate on average, while the second refrigerator has an average annual operating cost of $61. Second refrigerators are often smaller than the home’s most-used refrigerator, and they may not be in use the entire year—17% of homes with a second refrigerator reported that it was in use six months or less in 2015. Separate freezers cost $69 per year to operate on average.
1 Excludes losses in electricity generation and delivery.