DOE/EIA-0272/S The National

Interim Energy

Consumption Survey:

Exploring the Variability

in Energy Consumption 

-

A Supplement

October 1981

U.S. Department of Energy

Energy Information Administration

Office of Energy Markets and End Use
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contact.

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The National DOE/EIA"°Sc2

i

S3 

Interim Energy 

Consumption Survey:

Exploring the Variability

in Energy Consumption 

-

A Supplement

October 1981

U.S. Department of Energy

Energy Information Administration

Office of Energy Markets and End Use

Energy End Use Division

Washington, D.C. 20585
This report was prepared by Robert B. Latta.

Released for printing October 7, 1981.
PREFACE

This report supplements the report entitled, The National Interim Energy 

Consumption Survey; Exploring the Variability in Energy Consumption, which 

presented a preliminary analysis of residential energy consumption models for 

households living in single-family detached dwellings. In order to fully 

understand this report, it is necessary to also read the above report. The 

only fuels for which models were developed were electricity and natural gas. 

This report expands that analysis to fuel oil, kerosene, and liquid propane 

gas (LPG). In addition, models for households living in mobile homes, singlefamily attached dwellings, and units in small and large multi-family buildings 

are added whenever enough data are available to adequately estimate the terms 

in the model.

This report and the report it supplements will be of interest to researchers 

that are studying the possible impact of natural gas deregulation. This 

represents a large potential audience. The technical style in which this 

report is written reflects the audience for which it is written.
CONTENTS

Page

1. Introduction ............................ 1

2. Summary of Electricity and Natural Gas Models for Single

 Family Detached Dwellings .................... 2

3. Availability of Data for Extending Models ............. 6

4. Fuel Oil Model for Single-Family Detached Units .......... 13

5. Consumption Model for Other Housing Types and Fuels ........ 20

6. Discussion .............................24

Appendixes

A. NIECS Public Use File Variables Used in Consumption Models ... 25 

B. Outliers Detected in Estimating Consumption Models ....... 33

TABLES

1. Weighted Least Square Solution for Natural Gas Model

(Using NCNGYRB as the Dependent Variable) ............ 4

2. Weighted Least Square Solution for Electricity Model

(Using NCELYRB as the Dependent Variable) ............ 5

3. Total Households in the Sample that Use Electricity, Have

Good Data, Use Electricity for Main Heating Fuel and Have

Good Electricity Data (Classified by Housing Type) ........ 7

4. Total Households in the Sample that Use Natural Gas, Have

Good Data, Use Natural Gas for Main Heating Fuel, and Use

Natural Gas for Main Heating Fuel and Have Good Natural

Gas Data (Classified by Housing Type) .............. 8

5. Total Households in the Sample that Use Fuel Oil, Have Good 

Data, Use Fuel Oil for Main Heating Fuel, and Use Fuel Oil 

for Main Heating Fuel and Have Good Fuel Oil Data (Classified 

by Housing Type) ......................... 9

6. Total Households in the Sample that Use Kerosene, Have Good

Data, Use Kerosene for Main Heating Fuel, and Use Kerosene for

Main Heating Fuel and Have Good Kerosene Data (Classified

by Housing Type) ......................... 10

7. Total Households in the Sample that Use LPG, Have Good Data, 

Use LPG for Main Heating Fuel, and Use LPG for Main Heating 

Fuel and Have Good LPG Data (Classified by Housing Type) ..... 11

8. Analysis of Variance Table for Fuel Oil Model (Using NCFKYRB

as the Dependent Variable) .................... 14

9. Weighted Least Square Solution for Fuel Oil Model

(Using NCFKYRB as the Dependent Variable) ............ 15

10. Comparison of Estimated Fuel Oil, Natural Gas, and Electricity

Consumption for a Hypothetical Household .............18

11. Estimates of Coefficients (with Standard Errors) .......... 23

ii
Page

Al. Household Variables Selected for Use in the Analysis of 

Natural Gas, Electricity, Fuel Oil, Kerosene, and LPG 

Consumption ...........................26

A2. Household Variables Constructed for Use in the Analysis of 

Natural Gas, Electricity, Fuel Oil, Kerosene, and LPG 

Consumption ........................... 28

A3. Code for Household Income and Year House Built ........... 31

A4. Gas Appliance Index ........................32

Bl. Households that Were Detected as Outliers ............. 34

FIGURES

1. Scatter Plot of Residual Fuel Oil Model by Heating

Degree-Days ...........................16

iii

1. INTRODUCTION

The report, National Interim Energy Consumption Survey: Exploring the 

Variability in Energy Consumption, (DOE/EIA-0272), examined the variability in 

electricity and natural gas consumption for households living in single-family 

detached units. This report extends the results of the above-mentioned report 

to fuel oil, kerosene, LPG, and other housing types.

Section 1 summarizes the electricity and natural gas models that are contained 

in the above-mentioned report. In addition, the methodology that was used to 

obtain the models is reviewed.

In extending the results, the techniques used depended on the number of 

households available for a given fuel and housing type. Section 2 describes 

the amount of data available by fuel and housing type. There is enough data 

to fit the model for fuel oil use for households living in single-family 

detached dwellings. Section 3 gives the results for this model and compares 

it to the electricity and natural gas models. For other fuel and housing 

types, some adjustments to the model building methodology are necessary 

due to small sample sizes. Section 4 outlines the adjustments that were used, 

presents the modified models and discusses the results. Section 5 discusses 

all of the models and the limitations of their use and interpretation.
2. SUMMARY OF ELECTRICITY AND NATURAL GAS MODELS FOR 

SINGLE-FAMILY DETACHED DWELLINGS

The electricity and natural gas models are regression models that expressed 

the predicted electricity and natural gas consumption in MBtu (1000 Btu) as 

functions of characteristics of the household and housing unit. The models 

were developed using data from the National Interim Energy Consumption Survey 

(NIECS), which covers the period April, 1978 to March, 1979.

The details of the NIECS sampling plan are summarized in the report, 

National Interim Energy Consumption Survey; Exploring the Variability in 

Energy Consumption, (DOE/EIA-0272). A discussion on the theory behind the 

particular form of the models chosen and the choice of the independent vari 

ables that were used in the models is also contained in the report. The list 

of variables that were used in these models as well as those in this report 

are contained in Appendix A along with a brief description of what they 

measure.

Only those households living in single-family detached dwellings, having

good utility data and for which a personal interview was obtained were used in

the modeling procedure.

We felt that the dynamics of space-heating and cooling may differ appreciably 

between housing types. Consequently, we initially restricted consideration to 

households living in single-family detached dwellings because it was the 

dominant housing type.

Various techniques were used to convert electricity and natural gas billing 

period consumption data to an annual figure. See National Interim Energy 

Consumption Survey Report on Methodology Part I. Household and Utility 

Company Surveys, Response Analysis Corporation, Princeton, New Jersey for 

details. The cut-off point between the technique used for an intermediate 

amount of consumption data and the one used for "nearly" a full year of 

consumption data was 330 days. Therefore, we defined "good utility data" for 

electricity and natural gas as those annual consumption figures that were 

based on at least 330 days of consumption data.

The mail questionnaire did not contain all of the questions that we asked 

during a personal interview. Most of the household and housing unit charac 

teristics were imputed for households where a mail questionnaire was used. 

For this reason, we decided not to use households for which we did not have a 

personal interview.

For households where the household and housing unit data were obtained using a 

personal interview, there were still cases of nonresponses to various questions, 

If the nonresponse rate for a particular question was small, then the missing 

values were imputed. See National Interim Energy Consumption Survey Report
on Methodology, Part I. Household and Utility Company Surveys, Response 

Analysis Corporation, Princeton, New Jersey for details. This is not true for 

questions with a large number of nonresponses. The number of square feet of 

floor space in the residence and various measures of insulation fall into this 

last category.

We decided to treat the presence of imputed values, other than consumption 

figures, as part of the error term. When we did the analysis we did not have 

a data set available that indicated which responses were imputed. Taking the 

presence of imputed values into account would have delayed the analysis. 

There was some evidence that a large number of households had at least one 

response that was imputed. Removing these housholds from the data set may 

have greatly reduced the sample size available for building regression models.

The models were obtained using a form of robust regression that required 

several steps. The steps consisted of fitting least square solutions to the 

model and an outlier rejection procedure. The general linear model procedure 

of the SAS statistical package was used throughout.

In the first step of each analysis, parameters were fit to the data using 

ordinary least squares. For each succeeding step up to a total of seven, new 

parameters were fit using a weighted least squares procedure with the weights 

equal to the reciprocal of the estimated consumption from the previous step. 

The weights reflect the observation that there is a larger variance in energy 

use among households with high potential use than among those with low poten 

tial use.

At the third iteration, we began systematically eliminating outliers before 

refitting the models. The process of elimination and refitting was continued 

until no further outliers were removed, or until the seventh iteration was 

reached. For more details, see National Interim Energy Consumption Survey: 

Exploring the Variability in Energy Consumption, (DOE/ELA-0272).

The same procedure was used in obtaining the additional models presented 

in this report, but in all except one case, the only independent variables 

that were used were based on models from other cases. This will be discussed 

further in the next two sections.

Tables 1 and 2 give the final models obtained for natural gas and electricity 

consumption for households living in single-family detached dwellings.

The income variable used in the electricity consumption model is measured 

on an ordinal scale. This scale is given in Appendix A. It gives the cate 

gory in which the respondent places the household's income for 1977. The end 

points of the categories would have to be changed if the model is to be used 

with current income data.

The code for NGASNDX, the gas appliance index, and for KYHSBREC, year house 

built, are also given in Appendix A.
TABLE 1, WEIGHTED LEAST SQUARE SOLUTION FOR NATURAL GAS MODEL (USING NCNGYRB AS THE DEPENDENT VARIABLE).

PARAMETER

INTERCEPT

NGASNDX

NHSLDMEM*HGASUHT

HSBNMGSH

KMHTEC4RC

RADIATORS OR HOT WATER PIPES (1)

CENTRAL FORCED AIR <2>

OTHER (3)

NO GAS MAIN HEATING <4>

NHEATDD*HGASMHT*NBATHRMS

NHEATDD*HGASMHT*NAGE01

NHEATDD*HGASMHT*KYHSBREC

NHEATDD*HGASMHT*NROOMS

NHEATDD*HGASMHT*NDRSAWS

NHEATDD*HGASMHT*NSDRSAWS

NCOOLDD*NRMGASAC

T-STATISTIC FOR ATTAINED 2-SIDED STD ERROR OF 

ESTIMATE HOJ PARAMETERS LEVEL OF SIGNIFICANCE ESTIMATE

7.885.86117328 *

478.57038686

8.183.12797801

39,380.14733876

35.976.62454035 *

21.177.30479874 *

7.946.83589671 *

0.00000000 *

4.35890180

0.05823754

-1.12679365

1.14812215

0.36930515

-0.19222837

3.97906768

2.97

3.28

12.97

5.26

6.10

5.03

2.14

**

7.91

5.01

-8.12

6.45

7.11

-4.62

4.55

0.0030

0.0011

0.0001

0.0001

0.0001

0,0001

0.0323

**

0.0001

0.0001

0.0001

0.0001

0,0001

0.0001

0.0001

2.653.97724959

145.88367773

631.08680052

7.488.38074856

5.899.72507242

4.206.54981219

3.709.19030002

**

0.55073749

0.01163191

0.13882925

0.17801440

0.05192832

0.04156752

0.87531020

* THE SOLUTION IS NOT UNIQUE BECAUSE THE DESIGN MATRIX IS SINGULAR.

** NO TEST IS GIVEN BECAUSE THE ESTIMATE WAS ARBITRARILY SET EQUAL TO ZERO.
TABLE WEIGHTED LEAST SQUARE SOLUTION FOR ELECTRICITY MODEL (USING NCEL.YRB AS THE DEPENDENT VARIABLE).

PARAMETER

INTERCEPT

NELCKDV

KINCOME

NAOE01

NHSLDMEM

NHSLDMEM*HELWHT

HELWHT*HELDISHW

NELFRIG

HELBISHW

HELCLSDY

HSPFDFRZ

HAUTOWSH

NTOTAL

HSBNMELH

NHEATDO*HELMHT*HELHTPUM

NHEATDD*HELMHT*NAGE01

NHEA TDD*HELMHT*NBATHRMS

NHEATDD*HEL.MHT*NSDRSAWS

NHEATIin*HELMHT*NDRSAUS

NCOOLDD*NRMELRAC

NCOOLOD*NRMELRAC*K I NCOME

NCOOLDD*NRMELCAC*K INCOME

NCOQLDD*NRMELCAC

ESTIMATE

1*838.90033348

If 542. 91063357

249.49782225

-46.19145874

1-800.26754569

3 » 567. 83543487

SrOlO. 04258170

3 , 176. 9731 1550

3 » 246. 81 149591

3*827.05159181

4*456.46196110

2» 441. 14974480

108.33553652

3 , 282. 23 184877

-2.56940122

0.04376684

2.16693210

-0.11337950

0.31150668

0.69793901

0.07027372

0.12566062

0.41258501

T-STATISTIC FOR 

HO: PARAMETERS

1 . 32

6.06

2.47

-3.01

10.21

16.11

4.08

5.45

5.14

7.31

9.69

4.22

3.57

4.23

-2.72

4.27

5.19

-3.04

6.37

4.04

2.63

5.81

2.36

ATTAINED 2-SIDED 

LEVEL OF SIGNIFICANCE

0.1874

0.0001

0.0135

0.0026

0.0001

0.0001

0.0001

0.0001

0.0001

0.0001

0.0001

0.0001

0.0004

0.0001

0.0066

0.0001

0.0001

0.0024

0.0001

0.0001

0.0087

0.0001

0.0184

STD ERROR OF 

ESTIMATE

1»394. 29804463

254.42416974

100.89977992

15.32376895

176.30579562

221.41854047

1*227.15715352

582.64498142

631.57851582

523.81387074

460.08932694

577.80748929

30.34494681

776.69185130

0.94493510

0.01025377

0.41768602

0.03727163

0.04890592

0.17282322

0.02675765

0.02162087

0.17482890
3. AVAILABILITY OF DATA FOR EXTENDING MODELS

The number of households that use electricity is displayed in Table 3, natural 

gas in Table 4, fuel oil in Table 5, kerosene in Table 6, and LPG in Table 7. 

For each housing type, the tables give the number of households in the sample 

that use each fuel, the number of households for which we have good data, the 

number of households whose main heating equipment uses the fuel, and the 

number of households with good data whose main heating equipment uses the 

fuel.

For electricity and natural gas, "good data" implies the yearly consumption 

figure was based on at least 330 days of data and the household participated in 

a personal interview. For fuel oil, kerosene, and LPG, "good data" implies the 

supplier provided actual fuel purchase data from which an annual consumption 

amount could be obtained and the household participated in a personal interview^

In order for us to have "good data" for any fuel, the consumption for a 

particular household must be measured separately. Therefore, we should expect 

that few households living in large buildings will have "good data."

The consumption and cost figures for fuel oil and kerosene were combined on 

the NIECS data set. Only 882 of the households in the NIECS data set indicated 

that they used fuel oil or kerosene. Three of the 882 households did not list 

fuel oil or kerosene as the main space-heating, secondary space-heating, or 

water-heating fuel. One of the households listed fuel oil as the main spaceheating fuel and kerosene as the secondary space-heating fuel. For these four 

households, it is not clear which of the two fuels was actually consumed. For 

this reason, these four households were not classified as having good data for 

fuel oil or kerosene. They were arbitrarily classified as having consumed 

some fuel oil but not classified as having consumed some kerosene.

All households with good data paid their own utility bills. As a result, 

the models that were developed apply only to households that pay for their 

energy use directly. The energy consumption was imputed for households whose 

utility bills were part of the rent. Therefore, it would be difficult to 

make a comparison between the energy use of households that did and did not 

pay their own bills using the NIECS data set.

The following facts can be gleaned from Tables 3, 4, 5, 6, and 7.

 Most households live in single-family detached units.

 The total number of households that use electricity is 4,080. This is 

one less than the number of households in the data file.

 The dominant heating fuel is natural gas.
Table 3. Total Households in the Sample that Use Electricity, Have Good Data, Use Electricity for

Main Heating Fuel, and Use Electricity for Main Heating Fuel and Have Good Data (Classified 

by Housing Type).

Housing Type

Total That Use 

Electricity

Total That 

Have Good 

Electricity Data

Total That Use 

Electricity for 

Main Heating Fuel

Total That Use 

Electricity for Main 

Heating Fuel and Have 

Good Electricity Data

Unknown 11

Mobile Home 270 

(KTYPLVQT=1)

Single-Family 2,681 

Detached Unit 

(KTYPLVQT=2)

Single-Family 175 

Attached Unit 

(KTYPLVOT=3)

Building with 2-4 499 

Units 

(KTYPLVQT=5)

Building with 5 or 444 

More Units 

(KTYPLVQT=6)

2

177

2,147

128

256

160

1

70

368

22

67

129

0

55

301

14

29

44
Table 4. Total Households in the Sample that Use Natural Gas, Have Good Data, Use Natural Gas for Main 

Heating Fuel, and Use Natural Gas for Main Heating Fuel and Have Good Data (Classified by 

Housing Type).

Housing Type

Total That Use 

Natural Gas

Total That 

Have Good 

Natural Gas Data

Total That Use 

Natural Gas for 

Main Heating Fuel

Total That Use 

Natural Gas for Main 

Heating Fuel and Have 

Good Natural Gas Data

00

Unknown 10

Mobile Home 81 

(KTYPLVQT=1)

Single-Family 1,641 

Detached Unit 

(KTYPLVQT=2)

Single-Family 141 

Attached Unit 

(KTYPLVQT=3)

Building with 2-4 387 

Units 

(KTYPLVQT=5)

Building with 5 or 317 

More Units 

(KTYPLVQT=6)

2

44

1,285

92

169

69

9

74

1,510

127

317

201

2

42

1,188

82

132

47
Table 5. Total Households in the Sample that Use Fuel Oil, Have Good Data, Use Fuel Oil for Main 

Heating Fuel, and Use Fuel Oil for Main Heating Fuel and Have Good Data (Classified by 

Housing Type).

Housing Type

Total That Use 

Fuel Oil

Total That 

Have Good 

Fuel Oil Data

Total That Use 

Fuel Oil for 

Main Heating Fuel

Total That Use 

Fuel Oil for Main 

Heating Fuel and Have 

Good Fuel Oil Data

Unknown

Mobile Home 

(KTYPLVQT=1)

Single-Family 

Detached Unit 

(KTYPLVQT=2)

Single-Family 

Attached Unit 

(KTYPLVQT=3)

Building with 2-4 

Units 

(KTYPLVQT=5)

Building with 5 or 

More Units 

(KTYPLVQT=6)

39

536

21

99

97

12

355

11

25

39

532

21

97

96

12

353

11

25
Table 6. Total Households in the Sample that Use Kerosene, Have Good Data, Use Kerosene for Main Heating 

Fuel, and Use Kerosene for Main Heating Fuel and Have Good Data (Classified by Housing Type).

Housing Type

Total That Use 

Kerosene

Total That 

Have Good 

Kerosene Data

Total That Use 

Kerosene for 

Main Heating Fuel

Total That Use 

Kerosene for Main 

Heating Fuel and Have 

Good Kerosene Data

Unknown

Mobile Home 

(KTYPLVQT=1)

Single-Family 

Detached Unit 

(KTYPLVQT=2)

Single-Family 

Attached Unit 

(KTYPLVQT=3)

Building with 2-4 

Units 

(KTYPLVQT=5)

Building with 

More Units 

(KTYPLVQT=6)

5 or

33

53

21

32

32

49

21

32
Table 7. Total Households in the Sample that Use LPG, Have Good Data, Use LPG for Main Heating

Fuel, and Use LPG for Main Heating Fuel and Have Good Data (Classified by Housing Type).

Housing Type

Total That 

Use LPG

Total That Have 

Good LPG Data

Total That Use 

LPG for Main 

Heating Fuel

Total That Use 

LPG for Main 

Heating Fuel and 

Have Good LPG Data

Unknown

Mobile Home 

(KTYPLVQT=1)

Single-Family 

Detached Unit 

(KTYPLVQT=2)

Single-Family 

Attached Unit 

(KTYPLVQT=3)

Building with 2-4 

Units 

(KTYPLVQT=5)

Building with 5 or 

More Units 

(KTYPLVQT=6)

90

231

16

45

146

44

101

11

25

69
 We have good energy consumption data for most households living in 

single-family detached units but not for households living in multifamily units.

 In general, the LPG consumption data are not good.

 Most households that use natural gas use it as their main heating 

fuel. The same applies to fuel oil and kerosene.

Space-heating is an important part of any residential energy consumption 

model. In building regression models, it is wise to use only households for 

which we have good data. Therefore, the number of households in the sample 

that use a certain fuel for the main space-heating fuel and for which we have 

good data should be large if we are to construct a complete model for a 

particular fuel/housing type cell. The relatively large number of households 

of the above type for electricity/single-family detached units, natural 

gas/single-family detached units, and fuel oil/single-family detached units 

suggests that a reasonable model can be built for these cells from the NIECS 

data set. The models for electricity and natural gas were reviewed in Section 

1. The fuel oil model is presented in the next section. For the other cells, 

it was decided to use a modification of one of the models built for the three 

cells above. If there were less than 10 households with good data in a cell, 

no model was constructed.

12
4. FUEL OIL MODEL FOR SINGLE-FAMILY DETACHED UNITS

The same technique was used to construct a regression model that expresses the 

predicted fuel oil consumption in MBtu for single-family detached units as was 

used to model the electricity and natural gas consumption. This included 

iterative fittings of least square solutions with all but the first solution 

using weighted least squares. The same outlier rejection technique was used. 

Four iterations were used in constructing the fuel oil model. Only households 

with good fuel oil data were used.

Originally, it was decided to use the same terms in the fuel oil consumption 

model as were used in the natural gas consumption model. This would facilitate 

comparisons between the two models.

Unfortunately, only two of the households with good fuel oil data did not use 

fuel oil as the main space-heating fuel. Both of these households used fuel 

oil as the fuel for a secondary space-heating system but not for water-heating. 

These two households would determine the coefficient for secondary space-heating 

and have no effect on any other coefficient in the model. Consequently, these 

households were dropped from the model building data set and the term for 

secondary space-heating was dropped from the model.

One of the households indicated that they used fuel oil for cooking. No other 

household used fuel oil for any appliance except water-heating. This single 

household was also dropped from the fuel oil model building data set. No term 

for fuel oil appliances other than water-heating were used in the model.

The term HFOMHT x NHEATDD x NROOMS was originally included in the model. 

The resulting coefficient for this term was .1865 with a standard deviation 

of .3042. Therefore, the coefficient is not significantly different from 

zero. The colinearity of the measures of size of the housing unit makes 

the estimates of the coefficients corresponding to the measures unstable. 

Consequently, the models, even if they have the same terms, will not be 

comparable term by term. For these reasons, the term HFOMHT x NHEATDD x 

NROOMS was dropped from the model.

The terms used in the final model for fuel oil consumption in single-family 

detached units are HFOWHT x NHSLDMEM, KMHTEQRC, HFOMHT x NHEATDD x NBATHRMS, 

HFOMHT x NHEATDD x NAGE01, HFOMHT x NHEATDD x KYHSBREC, HFOMHT x NHEATDD x 

NDRSAWS, and HFOMHT x NHEATDD x NSDRSAWS. Where HFOWHT is an indicator 

variable for water-heating with fuel oil and HFOMHT is an indicator variable 

for main space-heating with fuel oil. The rest of the variables are the same 

as those used in the natural gas consumption model. They are all listed in 

Appendix A.

Tables 8 and 9 summarize the results of the final fuel oil consumption 

model. Two households were rejected as outliers in fitting the model. These 

are listed in Appendix B. Figure 1 is a scatter plot of the residual for the

13
TABLE 8. ANALYSIS OF VARIANCE TABLE FOR FUEL OIL MODEL (USING NCFKYRB AS THE DEPENDENT VARIABLE),

SOURCE

MODEL

ERROR

CORRECTED TOTAL

WEIGHTED 

DF SUM OF SQUARES MEAN SQUARE

8 7 r 822 , 798. 49945054 977*849.81243132

341 4.972.307.97412489 14.581.54831122

349 12-795.106.47357544

WEIGHTED 

ATTAINED LEVEL WEIGHTED STANDARD 

F VALUE OF SIGNIFICANCE R-SQUARE DEVIATION

67.06 0.0001 0.611390 120.75408
TABLE 9. WEIGHTED LEAST SQUARE SOLUTION FOR FUEL OIL MODEL (USING NCFKYRB AS THE DEPENDENT VARIABLE).

PARAMETER ESTIMATE

T-STATISTIC FOR 

HOI PARAMETERS

ATTAINED 2-SIDED 

LEVEL OF SIGNIFICANCE

STD ERROR OF 

ESTIMATE

HFKWHT*NHSLDMEM 

KMHTEQRC

RADIATOR OR HOT WATER PIPES (1)

CENTRAL FORCED AIR (2)

OTHER<3>

HFKMHT*NHEATD*NKATHR 

HFKMHT*NHEATD*NAGE01 

HFKMHT*NHEATD*KYHSBR 

HFKMHT*NHEATD*NDRSAW 

HFKMHT*NHEATD*NSDRSA

7*691.09303386

80*537.59547152

39*711.26026684

21*614.86923433

4.55597633

0.04407488

-0.96883482 

0.42827408

-0.15121750

4.29

9.17

6.67

3.17

5.79

2.51

-4.36 

5.29

-2. 27

0.0001

0.0001

0.0001

0.0017

0001

0.0126

0.0001

0.0001

0.0239

0

1*792.53277393

8*786.33497254

5*957.11506297

6*815.56893710

0.78636840

0.01757194

0.22235487

0.08090706

0.06667126
FIGURE 1. SCATTER PLOT OF RESIDUAL FOR FUEL OIL MODEL BY HEATING DEGREE DAYS.

RESIDUAL

<IN MILLION BTU>

150

125 1

100

75

50 •

25 •

0

-25

-50 •

-75 •

100

125 •

150

•

A

A

A

A

h

A

h A

A

A A

h A

A

A

A AA

1- B A

A A B B

B A AB AA

A A BA BA

h B B B A BAAA

A A A A A B B

C C A ABA

A ABA B

h B A AB

B A BBB

A BBA

A A BB

h A

B A

A

A

•

•

h

+ 1 i 1 i I

0 1000 2000 3000 4000 5000

B

A A

B

AA A

A

B

AE

A

A

B C

A

AC

BB

CB A

DA

AC

AC A

AE

C

AB

C

A

AB

A

A

A

A

A

A

A A A

B

A

B

A A A

B

A A A

A A A

B AA A

A A

B A

AAB

A C

E A AB

A A

B A

B A

B A A

A A A

B

A

6000

A

A

A

A

A

A

A

C A

BAA

B B

C A

A A A A

BA A

B A B A B

C A A

0 A A

BA B

A A AA

A BB A

C A A

A A A A

B A AA A

A

A A

A B

A

B

A B

A

A

A

+ i J.—.4. 4. _ J. _

7000 8000 9000 10000 11000 12000

HEATING DEGREE-DAYS

LEGENDS A=l OBSERVATION. B=2 OBSERVATIONS. ETC.
fuel oil model against NHEATDD and shows a drop at 9,000 heating degree-days. 

The same was shown in the corresponding plot for the natural gas model. Two 

logical explanations for this drop are better insulation and lower thermostat 

settings in the colder regions.

The value for mean square given in Table 8 can be used to give an approximate 

standard deviation to the estimated fuel oil consumption estimate. The approxi 

mate standard deviation equals the square root of (14,581.458 x YHAT), where 

YHAT is the estimated consumption. The form of the estimate comes from the 

use of 1/YHAT as the weight in the weighted least squares. For example, if 

YHAT equals 120,000, then an estimate of the standard deviation of YHAT is the 

square root of (120,000 x 14,581.548) which equals 41,830. This estimate is 

only approximate in that the error term is not normal, the weights are not 

exactly proportional to the variances, and the estimate does not take into 

account the clustering in the sample. In any case, it is evident that 

there is much variability in energy consumption among households with similar 

characteristics.

Table 10 displays the modeled fuel oil, natural gas, and electricity consumption 

for a hypothetical, but not necessarily typical, household. Each model has 

been estimated as if the particular fuel was used for water-heating and main 

space-heating. The natural gas and electricity models were adapted from 

Tables 7 and 8 of the report, National Interim Energy Consumption Survey: 

Exploring the Variability in Energy Consumption, (DOE/EIA-0272). The appliance 

terms in the electricity consumption model were condensed into one term. The 

same was done for the air conditioning terms. The intercept term in the fuel 

oil model is contained in the term for the type of heating equipment. Some of 

the terms do not have values for all three models. In these cases, that 

particular term is not included in all of the consumption models.

Due to differences in the composition of the terms in the models and because 

of colinearity problems, the results are not comparable term by term. In 

fact, the totals are not strictly comparable. If the appliances and air 

conditioning terms are subtracted, then the adjusted totals should display 

the modeled water-heating and space-heating components. The resulting 

adjusted totals are 138,448 MBtu for fuel oil, 163,204 MBtu for natural gas, 

and 60,352 MBtu for electricity.

When comparing the adjusted totals, it is not clear that the intercept terms 

for the natural gas and electricity models belong in the water-heating plus 

space-heating components. For natural gas, the intercept term represents the 

baseline for all households. The same applies to electricity. Only households 

that heat with fuel oil were used in constructing the fuel oil model. Conse 

quently, there is no intercept term for the fuel oil model.

The adjusted totals in themselves do not imply that it is more efficient to 

heat with electricity than fuel oil or, in turn, that it is more efficient 

than heating with natural gas. The Btu content of a fuel is measured as 

delivered to the household. But it takes several Btu of coal, oil, or natural

17
Table 10. Comparison of Estimated Fuel Oil, Natural Gas, and Electricitjr Consumption for a Hypothetical 

Household.

Independent Variable

Hypothetical 

Value

Contribution 

to Natural Gas

Fuel Oil Model Electricity 

Model (In MBtu) Model

Intercept - 

Appliances - 

Hot Water Heating (NHSLDMEM x H WHT) 4 x 

Type of Heating Equipment (KMHTEQRC) 2 

Electric Heat Pump (NHEATDD x HELMHT x HELHTPUM) 5,700 x

Heating/Measure of Size

NHEATDD x H MHT x NBATHRMS

NHEATDD x H MHT x NROOMS

NHEATDD x H MHT x NDRSAWS

oo Age of Respondent/Heating

NHEATDD x H MHT x NAGE01

Code for Year House Built/Heating

NHEATDD x H MIT x KYHSBREC

Storm Doors and Windows/Heating

NHEATDD x H MHT x NSDRSAWS

Air Conditioning

5,700 x

5,700 x

5,700 x

5,700 x

5,700 x

5,700 x

-

1 

1

1

1

1

1

1

1

x 1

x 2

x 7

x 18

x 40

x 5

x 12

0 

0 

30,764 

39,711

51,938

-

43,940

10,049

-27,611

-10,343

-

7,886 

8,136 

32,733 

21,177

49,691

45,810

37,891

13,278

-32,114

-13,148

33,424

1,839 

38,478 

14,271

-14,646

24,703

-

31,961

9,979

-

-7,755

11,910

138,448 204,764 110,740
gas to generate and deliver a Btu of electricity to a household. The difference 

between fuel oil and natural gas projected consumption statistics depends on 

the housing unit characteristics. If the heating systems for the hypothetical 

households were changed to systems that use radiators (KMHTEQRC = 1), the 

adjusted total for the fuel oil model would exceed the adjusted total for the 

natural gas model.

19
5. CONSUMPTION MODEL FOR OTHER HOUSING TYPES AND FUELS.

We decided that all housing type/fuel cells, except for single-family dwelling/ 

electricity, natural gas, and fuel oil, did not have enough households 

with good data to adequately fit a model with similar variables as those used 

in fitting the three excepted models. For those cells, we decided to use 

the same technique, but to condense the variables into three or fewer terms. 

These terms would be linear combinations of the variables that are parts of 

the entire solution of the models in the large cells.

For the electricity model for households living in housing types other

than single-family detached units, the model was based on the following three

terms:

ELBASE = 1,838.90

+1,542.91

+249.498

-46.1915

+1,800.27

+3,567.84

+5,010.04

+3,176.97

+3,246.81

+3,827.05

+4,456.46

+2,441.15

+108.336

+3,282.23

x NELCKDV

x KINCOME

x NAGE01

x NHSLDMEM

x HELWHT x NHSLDMEM

x HELWHT x HELDISHW

x NELFRIG

x HELDISHW

x HELCLSDY

x HSPFDFRZ

x HAUTOWSH

x NTOTAL

x HSBNMELH

ELHEATDD -2.56940 x NHEATDD x HELMUT x HELHTPUM 

+0.0437668 x NHEATDD x HELMHT x NAGE01

+2.16693 x NHEATDD x HELMHT x NBATHRMS 

-0.113379 x NHEATDD x HELMHT x NSDRSAWS 

+0.311507 x NHEATDD x HELMHT x NDRSAWS

ELCOOLDD 0.697939 x NCOOLDD x

+0.0702737 x NCOOLDD x

+0.412585 x NCOOLDD x

+0.125661 x NCOOLDD x

NRMELRAC

NRMELRAC x KINCOME

NRMELCAC

NRMELCAC x KINCOME

Note that these terms were derived intact from the solution to the electricity 

consumption model for single-family detached units. In using these three 

terms as the independent variables, we are assuming that ELBASE represents an 

index for electricity end uses that are not related to heating or cooling

20
degree-days, ELHEATDD is an index for electricity demand for primary spaceheating and ELCOOLDD is an index for electricity demand for cooling. The only 

other change in the model building technique was that the intercept was 

arbitrarily set equal to zero.

For the other fuel types, the heating component of the consumption models 

overshadows the other parts. For this reason, only one term was used in the 

cells with small numbers of households with good data. For natural gas and 

LPG, the single term used was the projected natural gas consumption given by 

the model for single-family detached dwellings. This projection is given by:

NGMODEL = 7,885.86

+478.570 x NGASNDX 

+8,183.13 x NHSLDMEM x HGASWHT 

+39,380.1 x HSBNMGSH 

+35,976.6 x HGSHTEQ1 

+21,177.3 x HGSHTEQ2 

+7,946.84 x HGSHTEQ3

+4.3589 x HGASMHT x NHEATDD x NBATHRMS 

+0.0582 x HGASMHT x NHEATDD x NAGE01

-1.1268 x HGASMHT x NHEATDD x KYHSBREC 

+1.1481 x HGASMHT x NHEATDD x NROOMS 

+0.3693 x HGASMHT x NHEATDD x NDRSAWS

-0.1922 x HGASMHT x NHEATDD x NSDRSAWS 

+3.9791 x NCOOLDD x NRMGASAC.

Here, HGSHTEQ1 is an indicator variable for gas main heating using radiators or 

hot water pipes; HGSHTEQ2 is an indicator variable for gas main heating using 

central forced-air; and HGSHTEQ3 is an indicator variable for other types of 

gas main heating equipment. For fuel oil and kerosene, the single term used 

was the projected fuel oil consumption given by the model for single-family 

detached dwellings. This projection is given by:

FOMODEL = 7,691.09 x HFOWHT x NHSLDMEM 

+80,537.60 x HFOMHT x HHEATEQ1 

+39,711.26 x HFOMHT x HHEATEQ2 

+21,614.87 x HFOMHT x HHEATEQ3

+4.5560 x HFOMHT x NHEATDD x NBATHRMS

+0.0441 x HFOMHT x NHEATDD x NAGE01

-0.9688 x HFOMHT x NHEATDD x KYHSBREC 

+0.4283 x HFOMHT x NHEATDD x NDRSAWS

-0.1512 x HFOMHT x NHEATDD x NSDRSAWS.

Here, HHEATEQ1 is an indicator variable for main space-heating using radiators 

or hot water pipes; HHEATEQ2 is an indicator variable for main space-heating 

using central forced-air; and HHEATEQ3 is an indicator variable for other types 

of main space-heating equipment. For kerosene, the terms HFOWHT and HFOMHT were 

changed to indicators for kerosene usage. In these cases, NGMODEL and FOMODEL 

represent indexes for potentia" nergy use.

21
The same technique was used as before including setting the intercept equal to 

zero.

Table 11 summarizes the results for the additional cells. The coefficients 

and their standard errors were obtained from the results of the final weighted 

least square regressions of the modeling procedures. A list of households 

rejected as outliers is given in Appendix B.

The standard errors shown in Table 11 are probably conservative in that they 

do not take the clustering in the sampling plan into account. They are shown 

in the table to give a bottom line to the precision of the estimates.

The listed coefficients in Table 11 are estimates of the proportion of

the single-family modeled consumption that we should expect in other cells.

For example, if the single-family electricity consumption model gives values

of ELBASE = 30,000 MBtu, ELHEATDD = 50,000 MBtu and ELCOOLDD = 20,000 MBtu,

then an estimate of the electricity consumption for a mobile home with

the same household and housing characteristics would be (30,000)(.96) +

(50,000)(1.00) + (20,000)(1.32) = 105,200 MBtu. If the single-family natural

gas consumption model gives an estimated consumption of 125,000 MBtu, then an

estimate for the LPG consumption for a household living in a single-family

detached dwelling that uses LPG for all of the same end uses and has the same

household and housing characteristics would be (125,000)(.81) = 101,250 MBtu.

The standard deviation of an estimated consumption for a household whose 

characteristics place it in a small cell should reflect not only the standard 

deviation of the proportion but also the standard deviation of the corresponding 

large cell consumption estimate. The impact of the second standard deviation 

tends to overshadow the first one.

The following general trends are illustrated in Table 11.

• Households living in large apartment buildings and paying their own 

utility bills tend to use less energy than households living in 

other housing types whose household characteristics are the same.

• The cooling degree-day component of the modeled yearly electricity 

consumption behaves differently than the heating degree-day component 

and the baseline component. In particular the coefficient for the 

cooling degree-day component tends to be larger than the other two 

components and larger than 1.0.

• Households that use LPG tend to use less energy than households with 

the same characteristics that use natural gas.

22
Table 11. Estimates of Coefficients (with Standard Errors).

Main Heating 

Fuel

N3

OJ

Housing lype ELBASE ELHEATDD ELCOOLDD NGMODEL FQMODEL

Electricity

Natural Gas

Fuel Oil

LPG

Kerosene

1 (Mobile Home) .96 (.04)

3 (Single-Family Attached) .84 (.03)

5 (Small Apartment Building) .86 (.03)

6 (Large Apartment Building) .68 (.03)

1

3

5

6

1

3

5

1

2

1

2

1.00 (.06) 1.32 (.20)

1.35 (.11) 1.31 (.16)

.80 (.09) 1.15 (.17)

.71 (.05) 1.17 (.17)

1.02 (

.90 (

1.02 (

.59 (

.77 (

.81 (

.05)

.04)

.03)

.03)

.06)

.03)

1.01 (.11)

1.01 (.11)

1.03 (.08)

1.01 (.06)

1.10 (.13)
6. DISCUSSION OF RESULTS

The reader must be careful not to place too much emphasis on the individual 

terms in the models. The coefficients for individual terms may be drastically 

altered by changing the set of independent variables in the regression equation 

or transforming the dependent variable. As a consequence, the coefficient for 

a particular independent variable could easily include the effect of other 

variables that are correlated with it. This applies to the three basic models 

as well as the modified models. It is much more relevant to consider the 

modeled total annual consumption of a hypothetical household as a value in 

itself and not as the sum of well-defined individual terms. The total itself 

is only meaningful for households whose independent variables are within the 

range used in constructing the model. The modeled consumption for a hypo 

thetical two-person household living in a house with eight bathrooms and 22 

other rooms may not be relevant.

The problems in using the individual terms in the consumption models can 

be illustrated by examining the term for the number of electric refrigerators 

in the electricity consumption model. The households used in constructing the 

electricity consumption model for households living in single-family detached 

houses can be broken down as follows: five of the households had no refri 

gerators; 1,735 had one; 393 had two; and 14 had three. Therefore, the 

coefficient for the term NELFRIG is based mainly on the comparison between the 

1,735 households with one refrigerator and the 393 households with two. It 

might be argued that the term applies mainly to the second refrigerator. The 

first refrigerator in the data set is the one the household designated as the 

most-used. In addition, the coefficient for NELFRIG may be measuring some 

other difference between the energy consumption of one- and two-refrigerator 

households. Even if the coefficient measured only the electricity consumption 

due to refrigerators, it would only be an average consumption. Refrigerators 

vary in size, age, design, and energy consumption. The model uses one value 

for all refrigerators.

The coefficients obtained for the modified models apply only to the linear 

combinations and not to the individual terms in the linear combinations. 

For example, the coefficients for NGMODEL in the natural gas consumption model 

for households living in large apartment buildings is .59. This does not 

imply that households living in apartments use 41 percent less hot water per 

capita than households living in single-family detached houses. It only 

implies that households paying their own utility bills and living in large 

apartment buildings use approximately 41 percent less natural gas annually 

than comparable households living in single-family detached homes.

24
Appendix A 

NIECS PUBLIC USE FILE VARIABLES USED IN CONSUMPTION MODELS

Table Al lists the household variables used in the construction of the 

consumption models. The variable names and values are documented in the NIECS 

public use file. Table A2 defines the variables used in the modeling process 

that are transformations of the variables in Table Al. Table A3 gives the 

codes for the variable KINCOME, household income, and the variable KYHSBREC, 

year house built. Table A4 gives the gas appliance index values for individual 

appliances. The value of NGASNDX, the gas appliance index, is the sum of the 

index values over all gas appliances in the housing unit.

25
Table Al. Household Variables Selected for Use in the Analysis of Natural 

GaS, Electricity, Fuel Oil, Kerosene, and LPG Consumption.

Variable Name Variable Description

HAUTOWSH

HCENTAC

HELCLSDY

HELDISHW

HELHTPUM

HELOVEN

HELRANGE

HROOMAC

HSPFDFRZ

KFLCNAC

KFLMHEAT

KFLSHEAT

KINCOME

KMHEATEQ

KREFRIG1

KREFRIG2

KWHEATFL

KYHSBREC

NAGE01

NCELYRB

Indicator Variable for Automatic Washing Machine

Indicator Variable for Central Air Conditioning

Indicator Variable for Electric Clothes Dryer

Indicator Variable for Electric Dish Washer

Indicator Variable for Electric Heat Pump

Indicator Variable for Electric Oven

Indicator Variable for Electric Range

Indicator Variable for Electric Room Air Conditioners

Indicator Variable for Separate Food Freezer

Code for Central Air Conditioning Fuel

Code for Main Heating System Fuel

Code for Secondary Heating System Fuel

Code for Household Income Level (see Table A3)

Code for Main Heating Equipment

Code for First Refrigerator Fuel

Code for Second Refrigerator Fuel

Code for Water Heating Fuel

Code for Year House Built (see Table A3)

Age of Respondent

Annual Consumption of Electricity in Thousands of Btu

26
Table Al. Household Variables Selected for Use in the Analysis of Natural 

Gas, Electricity, Fuel Oil, Kerosene, and LPG Consumption. 

(Continued)

Variable Name Variable Description

NCFKYRB

NCLPYRB

NCNGYRB

NCOMBATH

NCOOLDD

NDOORS1

NGASNDX

NHAFBATH

NHEATDD

NHSLDMEM

NREFRIG

NROOMAC

NROOMS

NSDOORS

NSTRMWIN

NSWINSGD

NUMWINDS

Annual Consumption of Fuel Oil and/or Kerosene in 

Thousands of Btu

Annual Consumption of LPG in Thousands of Btu

Annual Consumption of Natural Gas in Thousands of Btu

Number of Complete Bathrooms

Number of Cooling Degree-Days Based on 40-Year Average

Number of Outside Doors and Sliding Glass Doors

Gas Appliance Index (see Table A4)

Number of Half Bathrooms

Number of Heating Degree-Days Based on 40-Year Average

Number of Household Members

Number of Refrigerators

Number of Rooms Air Conditioned

Number of Rooms in House

Number of Storm Doors

Number of Storm Windows

Number of Storm Sliding Glass Doors

Number of Windows

27
Table A2. Household Variables Constructed For Use in the Analysis of Natural Gas, Electricity, Fuel 

Oil, Kerosene, and LPG Consumption.

00

Variable

HELFRIG1

HELFRIG2

HELFRIG3

HELHTPUM

HELMHT

HELWHT

HFOMHT

HFOWHT

HGASMHT

HGASWHT

Definition

1

0

1 

0

1 

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

if KREFRFL1 = 1 

otherwise

if KREFRFL2 = 1 

otherwise

if NREFRIG = 3 and KREFRFL1 = 1 

otherwise

if KMHEATEQ = 4 

otherwise

if KFLMHEAT = 5 

otherwise

if KWHEATFL = 5 

otherwise

if KFLMHEAT = 3 

otherwise

if KWHEATFL = 3 

otherwise

if KFLMHEAT = 1 

otherwise

if KWHEATFL = 1 

otherwise

Description

Indicator variable for electric 

refrigerator .

Indicator variable for electric 

refrigerator

Indicator variable for electric 

refrigerator.

Indicator variable for electric 

heat pump .

Indicator variable for electric 

main space-heating.

Indicator variable for electric 

water heating.

Indicator variable for fuel oil 

main space-heating

Indicator variable for fuel oil 

water heating.

Indicator variable for natural 

gas main space-heating.

Indicator variable for natural 

gas water heating .
Table A2. Household Variables Constructed For Use in the Analysis of Natural Gas, Electricity, Fuel 

Oil, Kerosene, and LPG Consumption (Continued).

VO

Variable

HKERMHT

HKERWHT

HLPMHT

HLPWHT

HSBNMELH

HSBNMGSH

HSBNMLPH

KMHTEQRC

Definition

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

2 

3

4

If KFLMHEAT = 4

otherwise

if KWHEATFL = 4

otherwise

If KFLMHEAT = 2

otherwise

if KWHEAT = 2

otherwise

if KFLSHEAT = 5 and KFLMHEAT £ 5

otherwise

if KFLSHEAT = 1 and KFLMHEAT ^ 1 

otherwise

if KFLSHEAT = 2 and KFLMHEAT jt 2

otherwise

if KFLMHEAT = 1 and KMHEATEQ = 1 

or 2 

if KFLMHEAT = 1 and KMHEATEQ = 3 

if KFLMHEAT = 1 and KMHEATEQ ^ 1, 

2, and 3 

if KFLMHEAT jt 1

Description

Indicator variable for kerosene

main space-heating .

Indicator variable for kerosene

water heating.

Indicator variable for LPG main

space-heating .

Indicator variable for LPG water

heating.

Indicator variable for electric

secondary but not main spaceheating .

Indicator variable natural gas 

secondary but not main spaceheating.

Indicator variable for LPG

secondary but not main spaceheating.

Class variable for gas main 

heating equipment. 

1 - System where heat is 

distributed by water 

2 - Central forced-air 

3 - Other (usually space-heater) 

4 - Nongas main heating
Table A2. Household Variables Constructed For Use in the Analysis of Natural Gas, Electricity, Fuel 

Oil, Kerosene, and LPG Consumption (Continued).

Variable

NBATHRMS

NDRSAWS

NELCKDV

NELFRIG

NRMELCAC

NRMELRAC

NRMGASAC

Definition

MCOMBATH +1/2 (NHAFBATH)

NDOORS1 + NUMWINDS

HELOVEN + HELRANGE

HELFRIG 1 + HELFRIG 2 + HELFRIG

0 if HCENTAC = 

0 if HCENTAC = 

NROOMAC-HROOMAC if HCENTAC =

0 if HROOMAC = 

1 if HROOMAC = 

NROOMAC if HROOMAC =

0 if HCENTAC = 

0 if HCENTAC = 

NROOMAC-HROOMAC if HCENTAC =

3

0 

1 and KFLCNAC = 1 

1 and KFLCNAC = 2

0 

1 and HCENTAC = 1 

1 and HCENTAC = 0

0 

1 and KFLCNAC = 2 

1 and KFLCNAC = 1

Description

Number of bathrooms .

Number of doors and windows.

Number of major electric cooking 

appliances.

Number of electric refrigerators.

Number of rooms potentially airconditioned by electric central 

units .

Number of rooms potentially airconditioned by electric room 

units .

Number of rooms potentially airconditioned by natural gas 

central units.

NSDRSAWS 

NTOTAL

NSDOORS + NSWINSGD + NSTRMWIN

NROOMS + NDOORS1 + NUMWINDS

Number of storm doors and windows.

Overall measure of the size of 

the house.
Table A3. Code for Household Income and Year House Built.

Variable Value Code

KINCOME

(Household Income)

KYHSBREC

(Year House Built)

1

2

3

4

5

6

7

8

9

10

11

12

13

14

1

2

3

4

5

6

7

Under

$3,000 -

$5,000 -

$8,000 -

$10,000 -

$12,000 -

$15,000 -

$20,000 -

$25,000 -

$30,000 -

$35,000 -

$40,000 -

$45,000 -

$50,000 or

In 1939 or

In 1940 -

In 1950 -

In 1960 -

In 1965 -

In 1970 -

In 1975 or

$3,000

$4,999

$7,999

$9,999

$11,999

$14,999

$19,999

$24,999

$29,999

$34,999

$39,999

$44,999

$49,999

more

earlier

1949

1959

1964

1969

1974

later

31
Table A4. Gas Appliance Index.

Appliance_______________________________Index Value 

Gas Clothes Dryer 7 

Gas Oven/Range 10 

Gas Refrigerator 12 

Outdoor Gas Light 18

32
Appendix B

OUTLIERS DETECTED IN ESTIMATING CONSUMPTION MODELS

The outliers detected in constructing the electricity and natural gas 

consumption models for households living in single-family detached houses are 

listed in Tables 3 and 6 of National Interim Energy Consumption Survey: 

Exploring the Variability in Energy Consumption, (DOE/EIA-0272). The outliers 

detected in constructing the other models are listed in Table Bl.

33
Table Bl. Households that Were Detected as Outliers.

Household ID of

Fuel

Fuel Oil

Electricity

Electricity

Electricity

Electricity

Housing Type Outliers (NSQIDDOE)

Single-Family Detached 1,278

3,772

Mobile Home 2,918

3,155

3,248

3,591

3,799

3,982

4,829

Single-Family Attached 1,174

2,648

2,854

3,757

4,688

Buildings with 2-4 units 1,359

1,597

2,123

3,897

3,946

Buildings with 5 or more units 3,102

3,310

LPG Single-Family Detached 2,520

•U.S. GOVERNMENT PRINTING OFFICE : 1981 0-361-068/1201

34
Other Reports Published by the Office of Energy Markets 

and End Use, End Use Energy Division;

Residential Energy Consumption Survey; Conservation, Feb. 1980, DOE/EIA-0207/3, 

GPO Stock No. 061-003-00087-8, $6.00.

Single-Family Households: Fuel Inventories and Expenditures; National Interim 

Energy Consumption Survey, Dec. 1979, DOE/EIA-0207/1, GPO Stock No. 061-003- 

00075-4, $1.75.

Residential Energy Consumption Survey; Characteristics of the Housing Stocks and 

Households, 1978, Feb. 1980, DOE/EIA-0207/2, GPO Stock No. 061-003-00093-2, $4.25.

Residential Energy Consumption Survey; Consumption and Expenditures, April 1979 

Through March 1979, July 1980, DOE/EIA-0207/5, GPO Stock No. 061-003-00131-9, 

$6.50.

Residential Energy Consumption Survey; Consumption Patterns of Household Vehicles, 

June to August, 1979, June 1980, DOE/EIA-0207/4, GPO Stock No. 061-003-00156-4, 

$3.75.

Nonresidential Buildings Energy Consumption Survey; Building Characteristics, 

March 1981, DOE/EIA-0246, GPO Stock No. 061-003-00171-8, $5.50.

Nonresidential Buildings Energy Consumption Survey; Fuel Characteristics and 

Conservation Practices, June 1981, DOE/EIA-0278, GPO Stock No. 061-003-00200-5, 

$8.00.

Residential Energy Consumption Survey; 1979-1980 Consumption and Expenditures, 

Part I; National Data (Including Conservation), April 1981, DOE/EIA-0262/1, GPO 

Stock No. 061-003-00191-2, $5.50.

Residential Energy Consumption Survey; 1978-1980 Consumption and Expenditures, 

Part II; Regional Data, May 1981, DOE/EIA-0262/2, GPO Stock No. 061-003-00189-1, 

$8.50.

The National Interim Energy Consumption Survey; Exploring the Variability in 

Energy Consumption, July 1981, DOE/EIA-0272, GPO Stock No. 061-003-00205-6, 

$4.25.

Copies of the above reports are available from:

Superintendent of Documents 

U.S. Government Printing Office 

Washington, D.C. 20402

National Interim Energy Consumption Survey; Household Interview File, DOE/DF-81-001 

(magnetic tape), available from the National Technical Information Service - Computer 

Products Division, 5285 Port Royal Road, Springfield, Virginia, Accession No. PB-81- 

108714, $125.00.
U.S. Department of Energy 

Energy Information Administration 

National Energy Information Center, El- 20 

Forrestal Building 

Washington, D.C. 20585

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