U.S. Energy Information Administration
(EIA)
Residential Energy Consumption Survey (RECS)
Document produced with information from the Web
http://www.eia.gov/
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EIA administers the Residential Energy Consumption Survey (RECS) to a nationally
representative sample of housing units. Specially trained interviewers collect energy
characteristics on the housing unit, usage patterns, and household demographics. This
information is combined with data from energy suppliers to these homes to estimate
energy costs and usage for heating, cooling, appliances and other end uses —
information critical to meeting future energy demand and improving efficiency and
building design.
First conducted in 1978, the thirteenth RECS was conducted in 2009. The 2009 survey
collected data from 12,083 households in housing units statistically selected to represent
the 113.6 million housing units that are occupied as a primary residence. Data from the
2009 RECS are tabulated for the four Census regions, the nine Census divisions, and 16
States. These 16 States vary in their geography, climate, and population size.
The results of each RECS include data tables, a microdata file, and a series of reports.
Data tables are generally organized across two headings; "Household Characteristics"
and "Consumption & Expenditures." See RECS data tables.
The RECS and many of the EIA supplier surveys are integral ingredients for some of
EIA's more comprehensive data products and reports, such as the Annual Energy
Outlook (AEO) and Annual Energy Review (AER). These products allow for broader
comparisons across sectors, as well as projections of future consumption trends.
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Where does RECS square footage data
come from?
RECS 2009 — Release date: July 11, 2012
The size of a home is a fixed characteristic strongly associated with the amount of
energy consumed within it, particularly for space heating, air conditioning, lighting, and
other appliances. As a part of the Residential Energy Consumption Survey (RECS),
trained interviewers measure the square footage of each housing unit. RECS square
footage data allow comparison of homes with varying characteristics. In-person
measurements are vital because many alternate data sources, including property tax
records, real estate listings, and, respondent estimates use varying definitions and underestimate square footage as defined for the purposes of evaluating residential energy
consumption.
What areas are included in RECS square footage?
In RECS, total square footage is a measurement of the two-dimensional area of the
housing unit that is enclosed from the weather, including exterior walls. This is also the
area where residential energy-consuming activities occur. Total square footage consists
of four areas: attic, basement, garage, and rest of home. These four areas are separately
measured by the interviewer because each may have its own heating and cooling
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characteristics. Attics are only measured if they are heated, cooled, or finished. Garages
are only measured if they are heated or cooled, and directly attached to the housing unit.
Trained interviewers use a standardized method for
measuring and collecting the dimensions of the housing
unit.
RECS housing units are measured during the in-person household interview. The
respondent reports the number of stories in the housing unit, characteristics of the
basement, attic, or garage, and the shape of each floor. Then the interviewer uses a
measuring tape to collect the dimensions of each floor of the housing unit.
Ideally, measurements are taken outside the housing unit to capture the total area of the
home. Where outside measurements are not possible (for example, a high-rise apartment
building), inside measurements are taken and adjusted for wall thickness after the
interview. For standard shaped floors (square, rectangle, T-, or L-shaped), the
dimensions are recorded as part of the questionnaire on the interviewer's laptop. For
floors with non-standard shapes, the interviewer sketches the shape on graph paper and
records the necessary dimensions on the sketch.
How are RECS square footage variables calculated?
Using the dimensions and sketches collected during the interview, a number of square
footage components are calculated, including each floor's area; attic, basement, and
garage areas where applicable; and heated and cooled spaces. Analysts later reviewed
unexpected or unusual values, as well as interviewer comments. When appropriate,
dimensions were corrected to accurately reflect the size and shape of the housing unit.
Missing measurement data is imputed. EIA uses a statistical process called hot-deck
imputation, where a case with missing data is randomly assigned the same data value as
a similar case. Characteristics such as housing unit type, number of stories, and number
of rooms are used to locate donors in the same "statistical neighborhood".
RECS provides the best square footage data for
understanding residential energy consumption
Due to a variety of factors, RECS square footage estimates may not be appropriate for
comparison with other data sources. Most other surveys, including the American
Housing Survey, rely on respondent estimates of a housing unit's size. Property tax
records and real estate listings often rely on in-person measurements, but included areas
differ by jurisdiction and housing unit type.
Analysis conducted by EIA suggests alternate data sources and respondent estimates of
square footage are typically much smaller than RECS measurements. For example,
unfinished basements are not commonly included in measurements used for property
tax assessments. Unfinished basements are an important part of RECS square footage
because they often contain major conditioning equipment and/or ductwork; thus, the
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area contributes to the housing unit's energy consumption and intensity. Most
respondents underestimate the size of their home as compared to the RECS
measurement. The magnitude of this error is related to the housing unit type and other
characteristics of the home, including the presence of basement, attic, and garage areas.
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How does EIA estimate energy
consumption and end uses in U.S.
homes?
RECS 2009 — Release date: March 28, 2011
EIA administers the Residential Energy Consumption Survey (RECS) to a nationally
representative sample of housing units. Specially trained interviewers collect energy
characteristics on the housing unit, usage patterns, and household demographics. This
information is combined with data from energy suppliers to these homes to estimate
energy costs and usage for heating, cooling, appliances and other end uses –
information critical to meeting future energy demand and improving efficiency and
building design.
RECS uses a multi-stage area probability design to
select sample
A multi-stage area probability design ensures the selection of a representative sample
ofhousing units in the United States.
All housing units in the 50 States and the District of Columbia that are occupied as
primary residences are eligible to be included in the RECS sample.
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Sample selection begins by randomly choosing counties. The selected counties are then
sub-divided into groups of Census blocks called segments and a sample of segments is
randomly drawn from the selected counties. Within each selected segment, a list of
housing units (sample frame) is created by field listing.1
The final sample of housing units is randomly selected from the housing unit frame
constructed from the selected area segments. This type of sampling is called a multistage area probability design. Its proper application ensures that the selected sample
represents the entire population of occupied housing units in the United States.
The number of counties, segments, and housing units to be selected are carefully
controlled so that RECS produces estimates of average energy consumption at specified
levels of precision within the following geographic levels, called domains: National,
Census Region, Census Division, and individual states or group of states within Census
Divisions.
An almost three-fold increase in sampled housing units is expected to result in more precise
estimates of average energy consumption in 2009
2005
2009
180
430
Segments
1,450
3,000
Census blocks
2,430
5,420
Housing units
4,380
12,100
Counties
Two surveys capture energy characteristics for
sampled housing units: the Household Survey and the
Rental Agent Survey
In the Household Survey, trained interviewers use a standardized questionnaire to
collect data from the selected housing units. The field interviewer uses a laptop to
record the householder's responses to the survey. This method of collecting data is
called Computer-Assisted Personal Interview (CAPI).
Questions in the Household Survey are designed to collect energy-related characteristics
of the housing unit ("What is the main fuel used for heating your home?"), as well as
energy usage patterns of the household members ("How often is your dishwasher
used?").
Where respondents in rental housing units are less sure of their housing unit's energy
characteristics, EIA uses the Rental Agent Survey. Those data are collected by phone or
in person from the unit's landlord or his/her representative.
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All of the data collected from the Household and Rental Agent Surveys go through a
series of rigorous statistical processes to ensure the highest possible data quality. These
processes include:



editing
validation and quality control
imputation of missing data
EIA collects consumption and expenditure data from
energy companies through the Energy Supplier Survey
After the Household and Rental Agent Surveys are completed, EIA conducts the Energy
Supplier Survey (ESS). ESS is a follow-on mail survey2 required of energy companies
that serviced housing units in the Household Survey. ESS gathers data on how much
electricity, natural gas, fuel oil, and propane were consumed by the sampled households
during the reference year. ESS also asks for actual dollar amounts spent on these energy
sources. Data from the ESS follow the same quality assurance procedures as those from
the Household and Rental Agent Surveys.
Did You Know?
According to the American Community Survey, in 2009 there are about 113.6 million
occupied housing units in the United States. About 19,000 were selected for RECS
interviews but only about 15,300 were occupied primary residences and eligible for
RECS. Of these, about 12,100 responded to the survey, a response rate of about 79%.
EIA produces estimates of end uses of energy by
modeling the data from the Household and Energy
Supplier Surveys
The flagship product of RECS is the estimate of how much energy is used within the
home for heating, cooling, refrigeration, and other end uses. EIA uses RECS to estimate
end-use consumption through a non-linear statistical model applied to data from the
Household and Energy Supplier Surveys, which disaggregates total energy consumption
into end-use components.
These estimates of energy end uses make RECS uniquely important: it is the only
survey that provides reliable, accurate and precise trend comparisons of energy
consumption between households, housing types, and areas of the country.
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