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Residential Energy Consumption Survey (RECS)

RECS Terminology

A B C D E F G H I J K L M N O P Q R S T U V W XYZ

A

Adequacy of Insulation: The respondent's perception about the acceptability of the housing unit's insulation.

Air Conditioning: A central (whole house), window/wall, or portable system for controlling the humidity, ventilation, and temperature in a building, typically to maintain a cool atmosphere in warm conditions. Nearly all air-conditioning units are fueled by electricity, although RECS captures some units that use natural gas. Consumption and cost estimates exclude attached fans or blowers, or evaporative cooling systems (swamp coolers).

Apartment: A self-contained housing unit that occupies only part of a multi-family residential building that has two or more housing units. Apartments may be owned by an owner/occupier or rented by tenants. This category includes condominium apartments (i.e. individually owned apartments), basement apartments, or other residential structures where units are stacked vertically. Housing units that are connected side-by-side by a wall that extends ground to roof are considered single-family attached units (i.e., a townhouse, row house, or duplex.) RECS categorizes apartments into those that are in buildings with two to four units—this category also includes houses originally intended for occupancy by one household (or for some other use) that have since been converted to separate dwellings for two to four households—and that are buildings with five or more units.

Appliances: Home appliances are electrical machines that accomplish some household function. Appliances include refrigerators, freezers, cooking equipment, laundry machines, dishwashers, and minor food-preparation machines. In early versions of RECS tables and analysis, appliances also included televisions and computers. In the RECS housing characteristics data tables, appliances are shown in one table. In RECS energy consumption and expenditures data tables, most appliances are grouped in the Other category, although refrigerators are a separate end use. (See End Use)

Appliance Efficiency Standards: The National Appliance Energy Conservation Act of 1987 required the Secretary of Energy to set minimum efficiency standards for various appliance categories and to make periodic updates. Appendix A from EIA's Annual Energy Outlook describes current standards and other legislation and regulations affecting the residential sector.

Attic: A space directly below the pitched roof of a home where a person has enough room to stand up. For RECS, attics are further defined as finished/unfinished, heated/unheated, and cooled/uncooled.

Attic Fan: Provides powered ventilation to cool an attic space by drawing in cooler outside air from attic vents (in soffits or gables) and pushing hot air to the outside.

Average Consumption: All estimates of average consumption are computed as weighted annual averages for all housing units that use a given fuel.  For consumption, averages are expressed as million Btu per housing unit or physical units per housing unit, for example kilowatthours (kWh) per housing unit for electricity or gallons per housing unit for fuel oil.

Average Expenditure: All estimates of average expenditures are computed as weighted annual averages for all housing units that use an end use or fuel. For fuel expenditures, averages are expressed as dollars spent on a given fuel per housing unit using the fuel. For end-use expenditures, averages are expressed as dollars spent on a given end use per housing unit using the end use.

B

Basement: One or more floors of a home that are either completely or partially below the ground floor where a person can walk upright. For RECS, basements are further defined as finished/unfinished, heated/unheated, and cooled/uncooled.

Bathroom: A full bathroom contains a sink with running water; a toilet; and either a bathtub, a shower, or both. A half bathroom contains a sink with running water and either a toilet, bathtub, or shower.

Bedroom: A room designed for sleeping, even if it is not presently used for sleeping. A one-room efficiency or studio apartment has no separate bedrooms.

Billing Period: For electricity and natural gas, the period of time between billing cycles. Consumption for the billing period is usually calculated by subtracting a meter reading on the billing period start date from the meter reading on the billing period end date. Occasionally, the billing period consumption is estimated. For bulk fuels, the billing period is the time between fuel deliveries.

Boiler: (See Steam or Hot-Water System)

Btu (British thermal units): A Btu is a traditional unit of heat defined as the amount of energy required to increase the temperature of 1 pound of water by 1 degree Fahrenheit, at normal atmospheric pressure. Energy consumption is expressed in Btu in the RECS tables and analyses to allow for consumption comparisons between fuels that are measured in different units. Heat content rates (i.e., thermal conversion factors) are in the Appendices of the Monthly Energy Review.

Built-in Electric Unit: An individual, resistance electric-heating unit that is permanently installed in the floors, walls, ceilings, or baseboards and is part of the electrical installation of the building. Electric space-heating devices plugged into an electric socket or outlet are not considered built in. (See Heating Equipment)

Built-in Oil or Gas Room Heater: Any of the following space-heating equipment:  circulating heaters, convectors, radiant gas heaters, or other nonportable room heaters.

Built-in Floor/Wall Pipeless Furnace: Space-heating equipment consisting of a ductless combustor or resistance unit that has an enclosed chamber where fuel is burned or where electrical-resistance heat is generated to warm the rooms of a building. A floor furnace is located below the floor and delivers heated air to the room or rooms immediately above it. A wall furnace is installed in a partition or in an outside wall and delivers heated air to the rooms on one or both sides of the wall. A pipeless furnace is installed in a basement and delivers heated air through a large register in the floor of the room or hallway immediately above.

C

CDD: (See Cooling Degree Days (CDD))

Ceiling Fan: A ceiling fan is an electrically powered fan that is suspended from the ceiling of a room that uses rotating paddles to circulate the air. Whole-house fans and attic fans are not ceiling fans.

Census Region and Division: A geographic area consisting of several states defined by the U.S. Census Bureau. The states are grouped into four regions and nine divisions. Because energy usage differs substantially within the division, since the 2009 RECS EIA further divides the Mountain Division into Mountain South (which includes Arizona, New Mexico, and Nevada) and Mountain North (which includes Colorado, Idaho, Montana, Utah, and Wyoming).

Region Division States
Northeast New England Connecticut, Maine, Massachusetts, New Hampshire, Vermont, and Rhode Island
  Middle Atlantic New Jersey, New York, and Pennsylvania
Midwest East North Central Illinois, Indiana, Michigan, Ohio, and Wisconsin
  West North Central Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota
South South Atlantic Delaware, the District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, and West Virginia
  East South Central Alabama, Kentucky, Mississippi, and Tennessee
  West South Central Arkansas, Louisiana, Oklahoma, and Texas
West Mountain* Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming
  Pacific Alaska, California, Hawaii, Oregon, and Washington
*Mountain South: Arizona, Nevada, and New Mexico
Mountain North: Colorado, Idaho, Montana, Utah, and Wyoming

Central Warm-Air Furnace: A type of space-heating equipment where a central combustor or resistance unit, generally using natural gas, fuel oil, propane, or electricity, provides warm air through ducts leading to various rooms. Consumption and expenditure estimates for furnaces exclude furnace fans and blowers. Heat pumps are not included in this category.

Climate Region : A set of climatically distinct areas, defined by long-term weather conditions affecting the heating and cooling loads in buildings. In 2009, RECS began using Building America Climate Regions which are defined using heating degree days, average temperatures, and precipitation data. Prior to 2009, RECS used seven distinct climate categories originally identified by the American Institute of Architects (AIA) for the U.S. Department of Energy and the U.S. Department of Housing and Urban Development. (See Cooling Degree Days (CDD) and Heating Degree Days (HDD))

Clothes Dryer: An appliance in the home that dries laundry using heat and rapid air movement. The hot air used can be heated by electricity, natural gas, or propane.

Clothes Washer: An appliance in the home used to wash laundry, such as clothing and sheets. Clothes washers can open from the top or front. The machine is powered by an electric motor.

Compact Fluorescent (CFL) Bulb: Lightbulbs that use fluorescent lighting technology, but in a format that can be used in common household lighting fixtures. CFLs are one of three types of lighting included in the 2015 RECS questionnaire.

Conditional End-Use Intensity (CEUI): A measure of energy efficiency that allows comparisons across housing units by adjusting either the end-use consumption or expenditures for the effects of certain characteristics, such as square footage or number of household members.

Condominium or Cooperative Fee: When living in condominiums or cooperatives, this fee is paid to the homeowners’ association for maintenance, management, insurance, and in some cases, utilities.

Condominium or Cooperative: (See Apartment)

Consumption: The amount of electricity or natural gas delivered to a housing unit during the reference year, or the amount of fuel oil/kerosene and propane purchased. Total site consumption in RECS tables and analysis includes electricity, natural gas, fuel oil/kerosene, and propane. Wood consumption estimates are also produced but not included in total site energy consumption.

Cooled Square Footage: The floor area in a housing unit that is cooled by any air-conditioning equipment.

Cooling Degree Days (CDD): A measure of how hot a location was over a period of time relative to a base temperature. In the RECS tables and analyses, the base temperature is 65 degrees Fahrenheit, and the period of time is one year. The cooling degree-days for a single day is the difference between that day's average outside temperature and the base temperature if the daily average is greater than the base; CDD is zero if the daily average outside temperature is less than or equal to the base temperature. The number of cooling degree days for a longer period of time is the sum of the daily cooling degree days for the days in that period. Local weather station CDD data (annual and 30-year averages) from the National Climate Data Center are linked to each RECS household case. (See Climate Region)

Cord of Wood: (See Wood Consumption)

Crawl Space: Space between the ground and the first floor of a house where a person cannot walk upright.

Cubic Foot (cf): Standard unit of volume used as a natural gas measure. The volume of gas contained in a 1x1x1 foot cube at standard temperature and pressure (60 degrees Fahrenheit and 14.73 pounds standard per square inch). (See Natural Gas)

Current Dollars: Unless otherwise noted, all dollar values in the RECS tables and analyses are expressed in the current dollars at the time of data collection. The dollar amounts have not been adjusted for inflation. In contrast, real dollars are current dollars that have been adjusted for  inflation.

D

Dishwasher: An appliance used for automatically cleaning dishware, utensils, and cutlery. As of 1988, dishwashers must be equipped with an option to dry without heat.

Distributed Solar Generation: Electricity generated at a housing unit through photovoltaic (PV) panels. (See Solar Energy)

E

End Use: A specific energy-consuming function for which fuels (energy sources) are ultimately used in the household. The amount of energy used for end uses is modeled using survey variables and weather data, rather than being directly measured. RECS has five energy consumption and expenditure end-use categories: Space Heating, Air Conditioning, Water Heating, Refrigerators, and Other (formerly referred to as Appliances).

Energy Supplier: A company that provides energy to customers. The RECS Energy Supplier Survey collects information from energy suppliers that provide electricity, natural gas, fuel oil, kerosene, or propane to households. The Energy Supplier Survey (ESS) does not collect information about wood usage or cash-and-carry bulk fuel purchases.

Ethnicity: The householder's self-identification as being Hispanic or Latino. RECS questions adhere to standards issued by the Office of Management and Budget (OMB), which specify that race and ethnicity are two separate and distinct concepts.

Evaporative Cooler (Swamp Cooler): A type of cooling equipment using the evaporation of water to cool air. This type of equipment is commonly found in warm, dry climates. Evaporative cooling units do not cool air by use of a refrigeration unit, so for the RECS tables and analyses they are not considered air-conditioning equipment.

Expenditures: Money charged for the energy delivered to a housing unit during a given period of time. For the RECS tables and analyses, all expenditure statistics are presented on an annualized basis. The total dollar amount includes base service charges and fees, and state and local taxes. It excludes late fees, one-time service fees, merchandise, and equipment repair charges. Electricity and natural gas expenditures are for the amount of those energy sources consumed. Fuel oil, kerosene, and LPG expenditures are for the amount of fuel purchased, which may differ from the amount of fuel consumed. For households that do not pay their fuel supplier directly, the expenditures for fuels are imputed. (See Consumption)

F

Fireplace: A structure made of brick, stone, or metal that is built into the wall and designed to contain a fire. A freestanding fireplace that can be detached from its chimney is a heating stove.

Freezer: An electric motor-driven refrigeration unit designed for storing food at temperatures of about 0 degrees Fahrenheit. A freezer is a stand-alone appliance, not part of a refrigerator, that can be an upright model (vertical unit with the door opening outward) or a chest model (horizontal unit with the door opening upward).

Frost-Free: A freezer, either separated from or attached to a refrigerator that automatically defrosts, usually on 12- or 24- hour cycles.

Fuel: The energy sources used by a household on site. The energy sources identified as a characteristic for the RECS tables and microdata files are electricity, natural gas, fuel oil/kerosene, propane, wood, and solar thermal. Fuel consumption and expenditures estimates are produced for electricity, natural gas, fuel oil/kerosene, and propane only. Wood consumption estimates are also produced but not included in total site consumption. (See Distributed Generation, Site Electricity, Natural Gas, Fuel Oil, Kerosene, Propane, Wood, and Solar Energy)

Fuel Oil: A subset of distillate fuel oil, which is a general classification of liquid petroleum products. Residential fuel oils are less volatile than gasoline and are burned for space heating or water heating. No. 2 fuel oil is the most common type used in homes. Because kerosene use is relatively rare, fuel oil and kerosene were combined into a single fuel category beginning with the 2015 RECS.

G

H

HDD: See Heating Degree Days (HDD).

Heat Pump: A heating and air-conditioning system in which refrigeration equipment can supply both heating and cooling. A heat pump generally consists of a compressor, both indoor and outdoor coils, and a thermostat.

Heated Square Footage: The floor area in a housing unit that is heated by any heating equipment.

Heating Degree Days (HDD): A measure of how cold a location was over a period of time, relative to a base temperature. In the RECS tables and analyses, the base temperature used is 65 degrees Fahrenheit and the period of time is one year. The heating degree days for a single day is the difference between the base temperature and the day's average outside temperature if the daily average is less than the base, and zero if the daily average outside temperature is greater than or equal to the base temperature. The heating degree days for a longer period of time are the sum of the daily heating degree-days for days in that period. Average daily temperature is the mean of the maximum and minimum temperature for a 24-hour period. Local weather station HDD data (annual and 30-year averages) from the National Climate Data Center are linked to each RECS household case. (See Climate Region)

Heating Equipment: The equipment used for heating ambient air in a housing unit, such as a central warm-air furnace; heat pump; built-in electric units; steam or hot-water system; floor, wall, or pipeless furnace; stove; room heater; fireplace; or portable heater. A cooking stove is sometimes reported as heating equipment, even if it was built for preparing food. (See Central Warm-Air Furnace; Heat Pump; Built-in Electric Units; Steam or Hot-Water System; Built-in Floor/Wall Pipeless Furnace; Heating Stove Burning Wood; Built-in Oil or Gas Room Heater, and Kerosene)

Heating Stove Burning Wood: A heating appliance that is freestanding or installed into the fireplace opening that can burn wood and wood-derived biomass fuel. Freestanding fireplaces that can be detached from their chimneys are considered heating stoves.

Household: A household consists of all people who either occupy a particular housing unit as their usual residence or who live there at the time of the interview, and have no usual residence elsewhere. Occupants can be related or unrelated. In the RECS tables and analyses, the number of households is the same as the number of occupied housing units.  (See Primary Residence)

Household Income: The total combined annual income from all sources (before taxes and deductions) from all household members. Sources of income include the following: wages, salaries, tips, commissions, interest, dividends, rental income, Social Security or railroad retirement, pensions, food stamps, Temporary Assistance for Needy Families (formerly Aid to Families with Dependent Children), unemployment compensation, supplemental security income, general assistance, and other public assistance.

Household Member: (See Household)

Householder: The person (or one of the people) in whose name the home is owned or rented. If the home does not have a lease or similar agreement, or if the person who owns the home or pays the rent does not live in the housing unit, the householder is the person responsible for paying the household bills or who is most knowledgeable about the home.

Housing Unit: A house, apartment, group of rooms, or single room if it is either occupied or intended for occupancy as separate living quarters by a family, an individual, or a group of unrelated persons. Separate living quarters means the occupants live and eat separately from other persons in the house or apartment and have direct access from the outside of the building or through a common hall—that is, they can get to their unit without going through someone else's living quarters. Housing units do not include group quarters such as dormitories or military barracks.

I

Incandescent Bulb: A type of lightbulb that produces visible light by heating a tiny coil or filament of tungsten wire via electric current to such a high temperature that it glows. Incandescent bulbs are one of three types of lighting included in the 2015 RECS questionnaire.

Intensities: The ratio of energy consumption or expenditures to another metric. In RECS, intensities are provided per housing unit, per household member, and per square foot.

J

 

K

Kerosene: A distilled product of oil or coal with the generic name kerosene, having properties similar to those of No. 1 fuel oil. Beginning with the 2015 RECS, kerosene is included with fuel oil.

Kilowatthour (kWh): A measure of electricity defined as a derived unit of work or energy, measured as 1 kilowatt (1,000 watts) of power expended for 1 hour. One kWh is equivalent to 3,412 Btu. (See Btu)

L

Light-Emitting Diode (LED) Bulb: A type of highly efficient directional lighting consisting of a two-lead semiconductor that emits light when activated. LEDs are one of three types of lighting included in the 2015 RECS questionnaire.

Liquefied Petroleum Gas (LPG): (See Propane)

Low-Income Home Energy Assistance Program (LIHEAP): A program that provides assistance to eligible low-income households in paying the costs of heating or cooling their housing units. States administer the program using federal government funds.

M

Master Metering: Measurement of electricity or natural gas consumption of several tenant units or housing units of a building (or group of buildings) using a single meter. Master metering is more common in older, multifamily apartment buildings. RECS identifies households that pay fuel costs through rent or condo fess, but does not specifically identify a housing unit that is part of a master-metered building.

Metric Conversion Factors: Estimates are presented in U.S. customary measures. Square footage estimates may be converted to metric units by using this relationship: 1 square foot is approximately equal to 0.0929 square meters. Energy estimates may be converted to metric units by using the relationship: 1 Btu is approximately equal to 1,055 joules and one kilowatthour (kWh) equals 3,600,000 joules. One gigajoule is approximately 278 kWh.

Metropolitan or Micropolitan Statistical Area: As defined by the U.S. Office of Management and Budget (OMB) a Metropolitan Statistical Area is a county or group of contiguous counties that contain at least one city of 50,000 inhabitants or more, or an urbanized area of at least 50,000 inhabitants and a total population of the metropolitan statistical area is at least 100,000 (75,000 in New England). For a Micropolitan Statistical Area, the principal city has at least 10,000, but not more than 50,000 inhabitants. The contiguous counties are included in a metropolitan or micropolitan statistical area if, according to certain criteria, they are essentially metropolitan in character and are socially and economically integrated with the central city.

Microwave Oven: A household cooking appliance with a compartment designed to cook or heat food by means of microwave radiation.

Mobile Home: A housing unit built off-site on a movable chassis and moved to a home site. A mobile home may be placed on a permanent or temporary foundation and may contain one or more rooms. A prefabricated or modular home assembled on site is a single-family housing unit and not a mobile home.

Multistage Area Probability Sample: A sample design executed in stages with geographic clusters of sampling units selected at each stage. This procedure reduces survey expenses for in-person surveys while maintaining representative national and subnational coverage.

N

Natural Gas: A naturally occurring hydrocarbon gas (mostly methane) delivered as an energy source to individual buildings by underground pipelines from a central utility company. Natural gas does not refer to propane. (See Propane)

O

Occupied Housing Unit: A unit with someone living in it as a usual or permanent place of residence.

Oven: An appliance with a thermally insulated compartment that supplies heat and is used for cooking food. Toaster ovens are not considered ovens. Ovens with a combined stove top or burners together in one unit are considered stoves (See Stove (Cooking) and Toaster Oven)

Owned/Rented: The relationship of a housing unit's occupants to the structure itself, not the land on which the structure is located. A housing unit is classified as Owned when it is occupied by someone in the household who is named on the deed, mortgage, or contract to purchase the unit. All other housing units are classified as Rented. The rent may be paid by an occupant, by someone not living in the unit, or the unit may be occupied rent free. Rent free means the unit is not owned by the occupant and no money is paid or contracted for rent. Such units are usually provided in exchange for services rendered or as an allowance or favor from a relative or friend not living in the unit. Unless shown separately, rent-free households are grouped with rented households.

P

Payment Method for Energy Bills: Method by which fuel suppliers or utility companies were paid for all electricity, natural gas, fuel oil, kerosene, or propane used by a household. Households responsible for paying energy suppliers directly are shown in RECS tables as All paid by household. Households who paid some fuel or end-use charges through rent or a condo fee are shown as Some paid, some included in rent or condo fee. Households for which all fuels and end uses were included in the rent or condo fee were classified as All included in rent or condo fee. If a household did not fall into any of those three categories, it was classified as Other. These are households for which fuel bills were paid by a third party such as a housing authority or a relative.

Portable Electric Heater: A heater that uses electricity and can be picked up and moved.

Portable Kerosene Heater: A heater that uses kerosene and can be picked up and moved.

Primary Electricity: The amount of electricity delivered to housing units as well as the energy used to produce and deliver the electricity. Primary electricity is site (delivered) electricity plus conversion losses in the generation process at the utility plant and energy losses incurred in transmission and distribution.  In all RECS tables and analyses, electricity is represented as site energy. (See Site Electricity)

Primary Residence: A housing unit in which a householder spends the largest part of the year and is the householder's usual or permanent place of residence. A primary residence is typically a year-round housing unit. If a seasonal unit happened to be occupied for at least half of the year by the householder, the unit would be considered a primary residence. (See Housing Unit)

Programmable Thermostat: A thermostat that can be programmed to adjust the temperature settings for a heating or cooling at predetermined times.

Propane: The most common type of liquefied petroleum gas (LPG) supplied to RECS households. Propane is usually delivered by tank trucks and stored near the residence in a tank or cylinder until used, but it can also be purchased in canisters from retail stores. In RECS tables and analyses, propane also includes similar fuel gases, such as butane, supplied to a residence in liquid form.

Public Housing: Housing units owned by a local housing authority or other local public agency, such as a housing and redevelopment authority or a housing development agency.

Q

Quadrillion (Quad): The quantity 1,000,000,000,000,000 = 1015 (10 to the 15th power). In the RECS tables, total site consumption is expressed in quadrillion Btu.

R

Race: The householder’s self-reported racial background. The race categories as defined in OMB's Statistical Policy Directive No. 15 include: white, black or African-American, American Indian or Alaskan Native, Asian, and Native Hawaiian or Other Pacific Islander. Respondents may choose more than one race. (See Ethnicity)

Radiator: A heating unit that is usually visible within the room or space to be heated and that transfers thermal energy via steam or hot water by conduction to the surrounding air.

Refrigerator: A household appliance that consists of a thermally-insulated compartment designed for storing food at a constant temperature a few degrees above the freezing point (32 degrees Fahrenheit). Most refrigerators have a second compartment for freezing and storing frozen foods at temperatures of 8 degrees Fahrenheit or below. 

Rent: (See Owned/Rented)

Residential Unit: A single-family home (attached and detached), apartment, or mobile home. RECS only includes housing units occupied as a primary residence. (See Household, Housing Unit, and Primary Residence)

Residential Energy Consumption Survey (RECS): A national, multistage probability sample survey conducted by the Office of Energy Consumption and Efficiency Statistics of the U.S. Energy Information Administration, U.S. Department of Energy. The RECS provides baseline information on how U.S. households use energy within the home.


Room: A distinguishable space within a housing unit, including living rooms, dining rooms, bedrooms, kitchens, lodgers' rooms, finished basements or attic rooms, recreation rooms, permanently enclosed porches that are suitable for year-round use, and other finished rooms. Bathrooms are classified separately. Not considered to be rooms in this survey are hallways, pantries, unfinished attics or basements, open porches, and unfinished space used for storage. (See Bathroom and Bedroom)

RSE Column Factor: (Shown on RECS tables from 2001 and earlier.) An adjustment factor that appears above each column of the detailed tables and is used to compute relative standard errors (RSEs). The column factor is equal to the geometric mean of the RSEs in a particular column of the main tables. (See Relative Standard Error and RSE Row Factor)

Relative Standard Error (RSE): A statistical measure of the extent to which a sample survey is likely to deviate from its true value in the population. An RSE provides an estimate of the sampling variability of a survey statistic relative to the survey statistic itself. RSEs are expressed on a percentage scale and included on a separate tab of each RECS data table. You can find guidance on interpreting an RSE or creating a confidence interval for an estimate at this EIA website.

RSE Row Factor: (Shown on RECS tables from 2001 and earlier.) An adjustment factor that appears to the right of each row of the detailed tables and is used to compute RSE's. The row factor is equal to the geometric mean of the RSE’s in a particular row of the main tables. (See Relative Standard Error and RSE Column Factor)

Rural: For the 2015 RECS, housing units were classified using criteria defined by the U.S. Census Bureau based on 2010 Census data. Rural areas are considered to be any area not in an urbanized area or urban cluster. Urbanized areas are densely settled groupings of blocks or tracts with 50,000 or more people, while urban clusters have at least 2,500 people, but less than 50,000 people. (See Metropolitan or Micropolitan Statistical Area and Urban)

S

Secondary Heating: Space-heating equipment and fuel used less often than the main space-heating equipment. For the 2015 RECS, respondents could select only one type of secondary heating. RECS respondents self-report their primary and secondary heating based on frequency of use, rather than the size of the heating equipment. Therefore, a respondent may report a natural gas furnace as secondary and an electric space heater as primary heating equipment.

Separate Cooktop: Burners that are used to cook food, but are not attached to an oven. Separate cooktops may use electricity, natural gas, or propane.  (See Stove (Cooking))

Single-Family Housing Unit: A housing unit either detached from or attached to another housing unit that typically provides living space for one household or family. Housing units that are connected side-by-side by a wall that extends ground to roof are considered single-family attached units (i.e., a townhouse, row house, or duplex.) A mobile home is not classified as a single-family home.

Site Electricity: The amount of electricity, in British thermal units (Btu) or kilowatthours, delivered to the housing unit. Site electricity does not include energy losses in generation and transmission. Site electricity is also known as delivered electricity. (See Primary Electricity)

Smart Meter: An electricity meter that allows two-way communication between the customer and energy supplier. A common feature of smart meters is the collection and storage of electricity usage at shorter time intervals (e.g., hourly or daily).

Smart Thermostat: An Internet-connected thermostat that can be programmed to adjust the temperature settings for heating or cooling at predetermined times. A smart thermostat may allow heating and cooling to be controlled remotely (e.g., through a smartphone.) Smart thermostat can also learn a household’s normal behaviors and adjust its schedule to maximize efficiency.

Solar Energy: The radiant light and heat from the sun, which can be converted into other forms of energy such as electricity. For RECS, Solar is classified as a fuel for solar thermal water heating or pool heating only. Distributed generation (i.e., solar PV) is classified as electricity and not as a separate fuel or energy source. (See Distributed Solar Generation)

Space Heating: The use of energy to generate heat in housing units using space-heating equipment. Heat may be provided by main or secondary space-heating equipment. Space heating does not include the energy used by furnace fans or blowers, nor does it include the use of energy to operate appliances, such as lights, televisions, and refrigerators, that give off heat as a byproduct. One of the major categories of energy end-use estimates in the RECS tables and analyses. (See End Use and Heating Equipment)

Square Footage: The floor area of the housing unit that is enclosed by exterior walls. In the RECS tables and analyses, square footage includes the following: basements, whether or not they contain finished space; finished and/or heated space in attics; and attached garages that are heated or cooled. Square footage does not include: crawl spaces, even if they are enclosed from the weather; unfinished or unheated attics; and sheds and other buildings that are not attached to the house. Also referred to as floorspace. (See also Heated Square Footage and Cooled Square Footage)

Steam or Hot-Water System: Either of two types of a central space-heating system that supplies steam or hot water to radiators, convectors, or pipes. The more common type supplies either steam or hot water from a boiler to conventional radiators, baseboard units, convectors, heating pipes embedded in the walls or ceilings, or heating coils or equipment that are part of a combined heating/ventilating or heating/air-conditioning system. The other type supplies radiant heat through pipes that carry hot water and are held in a floor.

Stove (Cooking): A cooking appliance that contains both a cooktop and an oven in one unit. Also known as a range. (See Separate Cooktop.)

Swimming Pool Heater: Optional heating equipment that maintains pool water temperature at a specified level.

Swimming Pool Pump: An electric pump for filtering and circulating pool water.

T

Temperature: Respondents’ reported estimates of the indoor temperature, which is typically the thermostat setting.

Thermostat: A device that senses the temperature of a system and adjusts the amount of heating and cooling produced and/or distributed.

Toaster Oven: Portable table-top or counter-top appliance used for heating or broiling food. Toaster ovens are not counted as ovens in the RECS. (See Oven.)

U

Urban: For the 2015 RECS, housing units were classified using criteria defined by the U.S. Census Bureau based on 2010 Census data. Urbanized areas are densely settled groupings of blocks or tracts with 50,000 or more people, while urban clusters have at least 2,500 people, but less than 50,000 people. All other areas are rural. Prior to 2009 RECS, urban and rural, as well as city and town designations, were self-reported by respondents. (See  Metropolitan or Micropolitan Statistical Area)

V

Vacant Housing Unit: A housing unit not occupied at the time of interview. An occupied seasonal or migratory housing unit is classified as vacant if all of its occupants had a usual place of residence elsewhere.

W

Water Heater: An automatically controlled, thermally insulated vessel that heats and stores water, or a tankless device that heats and transfers hot water on demand. In some systems, a boiler provides hot water and heat to the home. The water is heated by a coil that is part of the heating system and these systems do not have a separate hot water tank.

Water Heater Size: Respondents were asked the size of their water heater tank. Four categories were provided: small (30 gallons or less), medium (31 to 49 gallons), large (50 gallons or more), and tankless (or on-demand). Beginning with the 2015 RECS, respondents in apartments with a central water heating system were not asked this question.

Water Heating: The use of energy to heat water for hot running water. This category does not include energy used to heat water for cooking, hot drinks, or swimming pools. One of the major end-use categories in the RECS tables and analyses.

Well-water Pump: A pump that draws the water from a well below ground level up into the water pipes that circulate through the house.

Whole-house Fan: A type of fan installed in the ceiling of living space that is used for whole-house cooling by pulling in air from open windows and exhausting it into the attic. The whole- house fan should not be confused with an attic fan, which exhausts hot air from the attic only.

Windows: Openings in the housing unit envelope that contain framed glass. Generally, each window that opens separately is counted as one window. Double-hung slider windows count as one window. Panes of glass in a large window are not counted separately unless they open separately.

Wood (Fuel): Wood logs, chips, pellets, scraps, or wood products that are burned for heat or aesthetic value.

Wood Consumption: The amount of wood burned in a fireplace, stove, or furnace in the housing unit at any time during the reference year. Respondents report cut wood or wood logs in cords, which measure approximately 128 cubic feet. Pellets are reported as the number of 40 pound bags or the number of tons used.

 
XYZ

Year of Construction: The year the structure was originally completed. For mobile homes, year of construction is the model year.


Specific questions on this product may be directed to:

Chip Berry
James.Berry@eia.gov
RECS Survey Manager
Phone: (202) 586-5543