### CHAPTER 11. LIFE-CYCLE COST SUBGROUP ANALYSIS
TABLE OF CONTENTS
11.1 INTRODUCTION .................................................... 11-1 11.2 SENIOR AND LOW-INCOME HOUSEHOLDS ............................ 11-1 11.2.1 Subgroups Definition ............................................ 11-1 11.2.2 Inputs to the Subgroup Analysis for Senior-Only and Low-Income Households .................................................... 11-2 11.2.3 Results for Senior-Only and Low-Income Households .................. 11-3 11.3 NORTHERN AND SOUTHERN HOUSEHOLDS .......................... 11-5 11.3.1 Subgroups Definition ............................................ 11-5 11.3.2 Inputs to the Subgroup Analysis for Northern and Southern Households .... 11-7 11.3.3 Results for Northern and Southern Households

....................... 11-8 

### LIST OF TABLES
Table 11.2.1 RECS 2001 Definitions of Low-Income Households ................... 11-2 Table 11.2.2 Comparison of Input Values for All Households, Senior-Only Households,

and Low-Income Households ..................................... 11-3 Table 11.2.3 Non-Weatherized Gas Furnaces: LCC and PBP Results for Senior

Households .................................................... 11-4 Table 11.2.4 Non-Weatherized Gas Furnaces: LCC and PBP Results for Low-Income

Households .................................................... 11-5 Table 11.3.1 Definition of Northern and Southern Regions using 5,000 HDD Criteria ... 11-6 Table 11.3.2 Definition of Northern and Southern Regions using 6,000 HDD Criteria ... 11-7 Table 11.3.3 Comparison of Input Values for All Households, Northern, and Southern

Households .................................................... 11-8 Table 11.3.4 Non-Weatherized Gas Furnaces: LCC and PBP Results for Northern

Households (greater than 5,000 HDD) .............................. 11-9 Table 11.3.5 Non-Weatherized Gas Furnaces: LCC and PBP Results for Southern

Households (less than 5,000 HDD) ................................ 11-10 Table 11.3.6 Non-Weatherized Gas Furnaces: LCC and PBP Results for Northern



### Households (greater than 6,000 HDD) ............................. 11-11 Table 11.3.7 Non-Weatherized Gas Furnaces: LCC and PBP Results for Southern

Households (less than 6,000 HDD) ................................ 11-12 

### CHAPTER 11. LIFE-CYCLE COST SUBGROUP ANALYSIS
TABLE OF CONTENTS
11.1 INTRODUCTION

.................................................... 11-1 11.2 SENIORAND LOW-INCOME HOUSEHOLDS

............................ 11-1 11.2.1 Subgroups Definition

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-1 11.2.2 Inputs to the Subgroup Analysis for Senior-Only and Low-Income Households

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2 11.2.3 Results for Senior-Only and Low-Income Households

.................. 11-3 11.3 NORTHERN AND SOUTHERN HOUSEHOLDS

.......................... 11-5 11.3.1 Subgroups Definition

............................................ 11-5 11.3.2 Inputs to the Subgroup Analysis for Northern and Southern Households

.... 11-7 11.3.3 Results for Northern and Southern Households

....................... 11-8
LIST OFTABLES
Table 11.2.1 RECS 2001 Definitions ofLow-Income Households

................... 11-2 Table 11.2.2 Comparison ofInputValues for All Households, Senior-Only Households, and Low-Income Households

..................................... 11-3 Table 11.2.3 Non-Weatherized Gas Furnaces: LCC and PBP Results for Senior Households

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-4 Table 11.2.4 Non-Weatherized Gas Furnaces: LCC andPBP Results for Low-Income Households.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-5 Table 11.3.1 Definition ofNorthern and Southern Regions using 5,000 HDD Criteria .,. 11-6 Table 11.3.2 Definition ofNorthern and SouthernRegions using 6,000 HDD Criteria

... 11-7 Table 11.3.3 Comparison ofInputValues for All Households, Northern, and Southern Households.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-8 Table 11.3.4 Non-Weatherized Gas Furnaces: LCC and PBP Results for Northern Households (greaterthan 5,000 HDD)

.............................. 11-9 Table 11.3.5 Non-Weatherized Gas Furnaces: LCC and PBP Results for Southern Households (less than 5,000 HDD)

............................... , 11-10 Table 11.3.6 Non-Weatherized Gas Furnaces: LCC andPBP Results for Northern Households (greaterthan 6,000 HDD)

............................. 11-11 Table 11.3.7 Non-Weatherized Gas Furnaces: LCC and PBP Results for Southern Households (less than 6,000 HDD)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11-12

ll-i

### CHAPTER 11. LIFE-CYCLE COST SUBGROUP ANALYSIS

11.1 INTRODUCTION The intent of the consumer subgroup analysis is to evaluate impacts to identifiable groups of consumers who may be disproportionately affected by revised national energy efficiency standards. This is accomplished in part by analyzing the life-cycle cost (LCC) and payback periods (PBPs) for those households that fall into identifiable groups of consumers. In particular, DOE wishes to avoid negative impacts on identifiable population groups, such as senior-only and low-income households, that may not be able to afford significant increases in equipment price. For customers that are sensitive to price increases, increases in first costs of a product can preclude the purchase of a new model of that product. As a result, some customers may retain existing equipment longer than they otherwise would. These older products are generally less efficient to begin with, and their efficiency may deteriorate further if they are retained beyond their useful life. 

### DOE is also sensitive to the potential for revised national energy efficiency standards to have differential impacts on households in different regions of the country. Therefore, itevaluated the impacts of a revised standard for non-weatherized gas furnaces on northern (coldclimate) and southern (warm-climate) States. DOE evaluated only non-weatherized gas furnaces for the consumer subgroup analysis, since these units comprise the predominant product class, with shipments much larger than the other product classes.

11.2 SENIOR AND LOW-INCOME HOUSEHOLDS 11.2.1 Subgroups Definition The consumer subgroup analysis evaluated households with senior-only occupants or low income levels using non-weatherized gas furnaces. Senior-only households have occupants who are all at least 65 years of age. As defined in DOE's Energy Information Administration (EIA)'s Residential Energy Consumption Survey of 2001 (RECS 2001),' low-income households are considered to be those at or below the "poverty line." The "poverty line" varies with household size, head of household age, and family income. Table 11.2.1 summarizes the criteria given for selecting low-income households from the RECS 2001 sample. DOE applied an additional criterion to select only those low-income households who own their home, since renters do not purchase furnaces.

11-1 

### CHAPTER 11. LIFE-CYCLE COST SUBGROUPANALYSIS

11.1 INTRODUCTION
The intent ofthe consumer subgroup analysis is to evaluate impacts to identifiable groups ofconsumers who maybe disproportionately affected byrevised national energy efficiency standards. This is accomplished inpartby analyzing the life-cycle cost (LCC) andpayback periods (PBPs) for those households that fall into identifiable groups ofconsumers.
Inparticular, DOEwishes to avoid negative impacts onidentifiable population groups, such as senior-only and low-income households, thatmay notbe able to afford significant increases in equipment price. For customers that are sensitive to price increases, increases in first costs ofaproduct canpreclude the purchase ofa newmodel ofthatproduct. As a result, some customers may retain existing equipment longer than they otherwise would. These older products are generally less efficient to begin with, and their efficiency may deteriorate further if they are retainedbeyondtheiruseful life.
DOE is also sensitive to the potential for revisednational energy efficiency standards to have differential impacts onhouseholds in differentregions ofthe country. Therefore, it evaluated the impacts ofa revised standard for non-weatherized gas furnaces onnorthern (coldclimate) and southern (warm-climate) States.
DOE evaluated onlynon-weatherized gas furnaces for the consumer subgroup analysis, since these units comprise the predominantproduct class, with shipments much largerthanthe otherproduct classes.



### 11.2 SENIORAND LOW-INCOME HOUSEHOLDS
11.2.1 Subgroups Definition
The consumer subgroup analysis evaluatedhouseholds with senior-only occupants orlow income levels using non-weatherized gas furnaces. Senior-onlyhouseholds have occupants who are all atleast 65 years ofage. As defined in DOE'sEnergy InformationAdministration (EIA)'s Residential Energy Consumption Survey of2001 (RECS 2001),1 low-income households are consideredto bethose at orbelowthe "povertyline." The "poverty line" varies withhousehold size, head ofhousehold age, and family income. Table 11.2.1 summarizes the criteria given for selecting low-income households from the RECS 2001 sample. DOE applied an additional criterion to select onlythose low-income households who own theirhome, since renters do not purchase furnaces.

11-1

### Table 11.2.1 RECS 2001 Definitions of Low-Income Households Household Size Owner Age Family Income 1 65 and over less than $7,525 1 64 and under less than $8,163 2 65 and over less than $9,491 2 64 and under less than $10,507 3 Any less than $12,516 4 Any less than $16,036 5 Any less than $18,952 6 Any less than $21,389 7 Any less than $24,268 8 Any less than $27,091 9 or more Any less than $31,971



### 11.2.2 Inputs to the Subgroup Analysis for Senior

-Only and Low-Income Households DOE performed the consumer subgroup analysis by analyzing the LCC and payback periods of senior-only or low-income households with the spreadsheet models used for the LCC analysis. DOE used the same inputs in the subgroup analysis as it used in the LCC and PBP analysis (as described in Chapter 8) for non-weatherized gas furnace households considered to be senior-only or low-income.

### Table 11.2.2 summarizes the weighted-average input values for the senior-only and lowincome households analyzed in the consumer subgroup analysis and compares them to the weighted-average input values for all households in RECS 2001 using non-weatherized gas furnaces. The inputs for the senior-only and low-income subgroups do not differ significantly from the overall sample. 

### Table 11.2.1 RECS 2001 Definitions ofLow-Income Households Household Size



### 2 2 3 4 

### 5 6 7 8 9 ormore OwnerAge 65 and over 64 andunder 65 and over 64 andunder Any Any Any Any Any Any Any Family Income less than $7,525 less than $8,163 less than $9,491 less than $10,507 less than $12,516 less than $16,036 less than $18,952 less than $21,389 less than $24,268 less than $27,091 less than $31,971



### 11.2.2 Inputs to the Subgroup Analysis for Senior-Only andLow-Income Households
DOEperformed the consumer subgroup analysis by analyzing the LCC andpayback periods ofsenior-only orlow-income households with the spreadsheetmodels used for the LCC analysis. DOE usedthe same inputs inthe subgroup analysis as itused in the LCC and PBP analysis (as described in Chapter 8) for non-weatherized gas furnace households considered to be senior-only orlow-income.
Table 11.2.2 summarizes the weighted-average input values for the senior-only and lowincome households analyzed inthe consumer subgroup analysis and compares them to the weighted-average input values for all households inRECS 2001 using non-weatherized gas furnaces. The inputs for the senior-only and low-income subgroups do not differ significantly from the overall sample.

11-2

### Table 11.2.2 Comparison of Input Values for All Households, Senior-Only Households, and Low-Income Households Non-Weatherized Gas Furnace (NWGF) Category All Households Senior

-Only Low-Income Household Population Data Number of Household Records Sum of Weights (million households) Percent of NWGF Household Population 1880 43.5 100% 337

7.8 17.9% 152 3.4 7.8% Weighted

-Average Annual Energy Use for Baseline Furnace Space-Heating Natural Gas Use (MMBtu) Space-Heating Electricity Use (kWh) 56.6 496 55.3

508 51.5

488 Weighted

-Average Natural Gas Prices (2006$) Average Natural Gas Price ($/therm) Marginal Natural Gas Price ($/therm) 1.14 1.01 1.15

1.06 1.19

1.05 Weighted

-Average Electricity Prices (2006$) Average Electricity Price (0/kWh) Marginal Electricity Price (0/kWh) 10.8 10.7 11.0

10.4 11.2

10.5



### 11.2.3 Results for Senior-Only and Low-Income Households Tables 11.2.3 and 11.2.4 summarize the LCC results for senior-only and low-income households with non-weatherized gas furnaces. These results can be compared to the overall results in Table 8.4.1 in Chapter 8. The tables provide the average or mean LCC and PBP, the LCC savings relative to the base case, and the percentage of consumers for whom the LCC will decrease compared to the base case forecast (positive benefit), those for whom the LCC will increase compared to the base case forecast (negative impact), and those for whom the LCC will not change because the specific design option is less efficient or the same as the base case forecast for that house (and therefore the standard has no impact). The senior-only and low-income consumer subgroups show the same general pattern in average LCC savings and consumer impacts (i.e., percentage of consumers with net cost or benefit) as the overall population. For the 81 percent annual fuel utilization efficiency (AFUE) level, the average LCC savings and the percent of households that benefit for the subgroups is approximately the same as for all households with non-weatherized gas furnaces (see Table 8.4.1 in Chapter 8). For the 90 percent AFUE level, the average LCC savings and the percent of households that benefit is less favorable for senior and low-income households than for all households. This is due to the fact that the average baseline space-heating energy use is smallerfor senior and low-income households than for all households (mainly because senior and lowincome households tend to have smaller houses), so efficiency improvement yields less energy savings.

11-3 

### Table 11.2.2 Comparison ofInputValues for AU 

### Households, Senior-OnlyHouseholds, and Low-Income Households Non-Weatherized Gas Furnace (NWGF) Category All Households Senior-Only Low-Income Household Population Data Number ofHousehold Records Sum ofWeights (million households) Percent ofNWGF Household Population 1880 43.5 100% Weighted-AverageAnnualEnergy Use for Baseline Furnace Space-Heating Natural Gas Use (MMBtu) 56.6 Space-Heating ElectricityUse (kWh) Weighted-AverageNatural Gas Prices (2006$) Average Natural Gas Price ($/therm) MarginalNatural Gas Price ($/therm) Weighted-Average ElectricityPrices (2006$) Average Electricity Price (¢/kWh) Marginal Electricity Price (¢/kWh) 496

1.14 l.01

10.8 10.7



### 11.2.3 Results for Senior-Only and Low-Income Households 337 152 7.8 3A 17.9% 7.8%

55.3 5l.5 508 488

1.15 1.19 l.06 l.05

1l.0 11.2 lOA 10.5



### Tables 11.2.3 and 11.2.4 summarize the LCC results for senior-only and low-income households with non-weatherized gas furnaces. Theseresults canbe comparedto the overall results inTable 8.4.1 in Chapter 8. The tables provide the average ormeanLCC and PBP, the LCC savings relative to the base case, andthe percentage ofconsumers for whomthe LCC will decrease compared to the base case forecast (positive benefit), those for whomthe LCC will increase compared to the base case forecast (negative impact), and those for whomthe LCC will not change because the specific design optionis less efficient orthe same as the base case forecast for thathouse (and therefore the standardhas no impact).
The senior-only and low-income consumer subgroups showthe same generalpatternin average LCC savings and consumerimpacts (i.e., percentage ofconsumers withnet cost or benefit) as the overall population. Forthe 81 percent annual fuel utilization efficiency (AFUE) level, the average LCC savings andthepercent ofhouseholds thatbenefit for the subgroups is approximately the same as for all households withnon-weatherized gas furnaces (see Table 8.4.1 in Chapter 8). Forthe 90percentAFUE level, the average LCC savings andthe percent of households thatbenefit is less favorable for senior and low-income households than for all households. This is due to the fact that the averagebaseline space-heating energyuse is smaller for senior and low-income households than for all households (mainly because senior and lowincome households tend to have smallerhouses), so efficiency improvementyields less energy savmgs.

11-3

### Table 11.2.3 Non-Weatherized Gas Furnaces: LCC and PBP Results for Senior Households

Life-Cycle Cost Life-Cycle Cost Savings Payback Period (Years)** Design Option Average Average Households with Average Avera e by AFUE Installed Operating LCC g Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $1,910 $10,010 $11,920 80% $1,918 $9,810 $11,728 $1 0% 99% 1% 0.7 0.8 80% Modulation $2,195 $9,892 $12,087 -$246 67% 32% 1% 42 73 (Two-Stage) 81% $1,989 $9,713 $11,702 $11 32% 32% 36% 11 22 81% Modulation $2,266 $9,796 $12,062 -$238 65% 32% 3% 39 73 (Two-Stage) 90% $2,566 $9,007 $11,573 $36 38% 32% 30% 12 18 92% $2,728 $8,854 $11,582 $17 43% 26% 31% 13 20 92% Modulation $2,965 $8,965 $11,930 -$323 80% 2.7% 17% 20 47 (Two-Stage) 92% Modulation $3,004 $9,090 $12,094 -$481 85% 2.7% 12% 22 59 (Continuous) 96% Modulation $3,614 $8,812 $12,426 -$806 88% 2.7% 10% 30 74 (Continuous) * "No impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. ** Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator. 

### Table 11.2.3 Non-Weatherized GasFurnaces: LCC andPBPResults for Senior Households Life-Cycle Cost Life-Cycle CostSavings PaybackPeriod (Years)** Design Option Average Average Households with by AFUE Installed Operating Average Average LCC Savings Net No *

# I**B:~t** Median Average Price Cost Cost Impact* eftt 78% $1,910 $10,010 $11,920 80% $1,918 $9,810 $11,728 $1 0% 99% 1% 0.7 0.8 80% Modulation $2,195 $9,892 $12,087 -$246 67% 32% 1% 42 73 (Two-Stage) 81% $1,989 $9,713 $11,702 $11 32% 32% 36% 11 22 81%Modulation $2,266 $9,796 $12,062 -$238 65% 32% 3% 39 73 (Two-Stage) 90% $2,566 $9,007 $11,573 $36 38% 32% 30% 12 18 92% $2,728 $8,854 $11,582 $17 43% 26% 31% 13 20 92% Modulation $2,965 $8,965 $11,930 -$323 80% 2.7% 17% 20 47 (Two-Stage) 92% Modulation $3,004 $9,090 $12,094 -$481 85% 2.7% 12% 22 59 (Continuous) 96% Modulation $3,614 $8,812 $12,426 -$806 88% 2.7% 10% 30 74 (Continuous) 

## * "No Impact" means that the base case forecast furnace assigned to the household has greater efficIency than the level indicated, so the household is not affected. 

## ** Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator.

11-4

### Table 11.2.4 Non-Weatherized Gas Furnaces: LCC and PEP Results for Low-Income Households

Life-Cycle Cost Life-Cycle Cost Savings Payback Period (Years) Design Option Average Average Households with Average Avera e by AFUE Installed Operating LCC g Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $1,877 $9,233 $11,111 80% $1,885 $9,052 $10,937 $2 0% 98% 2% 1.4 2.4 80%Modulation $2,156 $9,146 $11,302 -$260 69% 28% 3% 36 70 (Two-Stage) 81% $1,955 $8,965 $10,920 $11 35% 28% 37% 12 31 81%Modulation $2,226 $9,058 $11,285 -$252 67% 27% 5% 34 71 (Two-Stage) 90% $2,519 $8,328 $10,847 $39 46% 27% 26% 17 29 92% $2,675 $8,190 $10,865 $20 52% 20% 29% 17 32 92% Modulation $2,906 $8,308 $11,214 -$324 80% 1.3% 18% 26 70 (Two-Stage) 92% Modulation $2,944 $8,426 $11,370 -$477 84% 1.3% 15% 29 92 (Continuous) 96%Modulation $3,536 $8,180 $11,716 -$821 86% 1.3% 12% 38 111 (Continuous) "No impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator.



### 11.3 NORTHERN AND SOUTHERN HOUSEHOLDS 11.3.1 Subgroups Definition DOE analyzed the impact of standards for non-weatherized gas furnaces on households located in northern (cold-climate) and southern (warm-climate) regions. To conduct this analysis, DOE divided the States into northern and southern regions. It defined the southern region as comprising States with an average of fewer than 5,000 heating degree days (HDD), and the northern region as comprising states with an average of more than 5,000 HDD (Table 11.3.1). DOE also performed an analysis using a definition of the southern region as comprising States with an average of fewer than 6,000 HDD, and a definition of the northern region as comprising states with an average of more than 6,000 HDD (Table 11.3.2.).

11-5 

### Table 11.2.4 Non-Weatherized Gas Furnaces: LCC andPBPResults for Low-Income Households Life-Cycle Cost Life-Cycle CostSavings PaybackPeriod (Years)** Design Option Average Average Households with byAFUE Installed Operating Average Average LCC Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $1,877 $9,233 $11,111 80% $1,885 $9,052 $10,937 $2 0% 98% 2% 1.4 2.4 80% Modulation $2,156 $9,146 $11,302 -$260 69% 28% 3% 36 70 (Two-Stage) 81% $1,955 $8,965 $10,920 $11 35% 28% 37% 12 31 81% Modulation $2,226 $9,058 $11,285 -$252 67% 27% 5% 34 71 (Two-Stage) 90% $2,519 $8,328 $10,847 $39 46% 27% 26% 17 29 92% $2,675 $8,190 $10,865 $20 52% 20% 29% 17 32 92% Modulation $2,906 $8,308 $11,214 -$324 80% 1.3% 18% 26 70 (Two-Stage) 92% Modulation $2,944 $8,426 $11,370 -$477 84% 1.3% 15% 29 92 (Continuous) 96% Modulation $3,536 $8,180 $11,716 -$821 86% 1.3% 12% 38 III (Continuous) 

## * "No Impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. 

## * * Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably abetter indicator.



### 11.3 

### NORTHERNAND SOUTHERNHOUSEHOLDS
11.3.1 

### SubgroupsDefinition
DOE analyzedthe impact ofstandards for non-weatherized gas furnaces onhouseholds located in northern (cold-climate) and southern (warm-climate) regions. To conduct this analysis, DOE divided the States into northern and southernregions. It

### definedthe southern region as comprising States with an average offewer than 5,000 heating degree days (HDD), and the northernregion as comprising states with an average ofmore than 5,000 HDD (Table 11.3.1). DOE also performed an analysis using a definition ofthe southernregion as comprising States with an average offewer than 6,000 HDD, and a definition ofthe northernregion as comprising states with an average ofmore than 6,000 HDD (Table 11.3.2.).

11-5

### Table 11.3.1 Definition of Northern and Southern Regions using 5 ,000 TODD Criteria Region Census Divisions and States Represented

Four Large States New England Connecticut, Maine, Massachusetts, New Hampshire, Vermont, and Rhode Island Middle Atlantic' New Jersey and Pennsylvania Northern East North Central Illinois, Indiana, Michigan, Ohio, and Wisconsin (cold-climate) West North Central Iowa Kansas Minnesota Missouri Nebraska North Dakota and States , , , , , , South Dakota Mountain (HDD>5,000)b Colorado, Idaho, Montana, Nevada, Utah, and Wyoming Pacific` Alaska, Oregon, and Washington New York New York South Atlantic' Delaware, the District of Columbia, Georgia, Maryland, North Carolina, South Carolina, Virginia, and West Virginia East South Central Alabama, Kentucky, Mississippi, and Tennessee Southern West South Central' Arkansas, Louisiana, and Oklahoma (warm-climate) Mountain (HDD<5 000)b Arizona and New Mexico States ,

California California Texas Texas Florida Florida (a) Not including New York, which is included separately as one of the four large States. (b) DOE assumed that, using this criterion, most households in the northern region would come from Colorado, Idaho, Montana, Nevada, Utah and Wyoming, while most households in the southern region would come from Arizona and New Mexico. (c) Not including California, which is included separately as one of the four large States.. (d) Not including Texas, which is included separately as one of the four large States. West Virginia is included in the southern region, even though it has an average of more than 5,000 HDDs. (e) Not including Florida, which is included separately as one of the four large States. 

### Table 11.3.1 Definition ofNorthern and SouthernRegions using 5,000 HDD Criteria Region

Northern (cold-climate) States Census Divisions and Four Large States NewEngland

Middle Atlantica EastNorth Central WestNorth Central

Mountain (HDD>5,000)b PacificC NewYork South Atlanticd

East South Central Southern West South Centrale (warm-climate) Mountain (HDD<5,000)b States California Texas Florida States Represented
Connecticut, Maine, Massachusetts, NewHampshire, Vermont, and Rhode Island NewJersey and Pennsylvania Illinois, Indiana, Michigan, Ohio, andWisconsin Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota Colorado, Idaho, Montana, Nevada, Utah, andWyoming Alaska, Oregon, andWashington NewYork Delaware, the District ofColumbia, Georgia, Maryland, North Carolina, South Carolina, Virginia, and WestVirginia Alabama, Kentucky, Mississippi, and Tennessee Arkansas, Louisiana, and Oklahoma Arizona andNewMexico California

Texas Florida (a) NotincludingNewYork, which is included separately as one ofthe four large States. (b) DOE assumed that, using this criterion, mosthouseholds in the northern region would come from Colorado, Idaho, Montana, Nevada, Utah andWyoming, while most households in the southern region would come from Arizona and NewMexico. (c) Notincluding California, which is included separately as one ofthe four large States

.. (d) Not including Texas, which is included separately as one ofthe four large States. West Virginia is included in the southern region, even though ithas an average ofmore than 5,000 HDDs. (e) Notincluding Florida, which is included separately as one ofthe four large States.

11-6

### Table 11.3.2 Definition of Northern and Southern Regions using 6,000 HDD Criteria



### Region Census Divisions

and Four Large States 

### States Represented

northern cold-climate) States

southern (warm-climate) States New England

(HDD>6,000)a East North Central West North Central Mountain Pacific' New York New England (HDD>6,000)' Middle Atlantic' East North Central West North Central South Atlantic'

East South Central West South Central' Mountain(HDD<6, 000)b Pacific' California
Texas Florida Connecticut, Maine, Massachusetts, New Hampshire, and Vermont
Illinois, Michigan, and Wisconsin Iowa, Minnesota, Nebraska, North Dakota, and South Dakota Colorado, Idaho, Montana, Utah, and Wyoming

Alaska New York Rhode Island
New Jersey and Pennsylvania Indiana and Ohio Kansas and Missouri Delaware, the District of Columbia, Georgia, Maryland, North Carolina, South Carolina, Virginia, and West Virginia Alabama, Kentucky, Mississippi, and Tennessee Arkansas, Louisiana, and Oklahoma Arizona, Nevada, and New Mexico Hawaii, Oregon, and Washington

California Texas Florida (a) DOE assumed that, using this criterion, most households in the northern region would come from Connecticut, Maine, Massachusetts, New Hampshire, and Vermont, while most households in the southern region would come from Rhode Island

. The same criterion applies to the other split divisions. (b) Not including California, which is included separately as one of the four large States. (c) Not including New York, which is included separately as one of the four large States. (d) Not including Texas, which is included separately as one of the four large States. (e) Not including Florida, which is included separately as one of the four large States.


### 11.3.2 Inputs to the Subgroup Analysis for Northern and Southern Households DOE performed the consumer subgroup analysis by analyzing the LCC and PBP of northern and southern households with the spreadsheet models used for the LCC analysis. DOE used the same inputs in the subgroup analysis as it used in the LCC and PBP analysis (as described in Chapter 8) for non-weatherized gas furnace households considered to be northern or southern households.

11-7 

### Table 11.3.2 Definition ofNorthern and SouthernRegions using 6,000 HDD Criteria Region Census Divisions States Represented andFourLarge

northern (cold-climate) States

southern (warm-climate) States 

### States NewEngland (HDD>6,OOO)" EastNorth Central WestNorth Central Mountain

Pacificb
NewYork NewEngland (HDD>6,ooo)a Middle AtianticC
EastNorth Central WestNorth Central

South Atlanticd

East South Central West South Centrale Mountain(HDD<6,OOO)b PacificC California

Texas Florida Connecticut, Maine, Massachusetts, New Hampshire, and Vermont
Illinois, Michigan, andWisconsin Iowa, Minnesota, Nebraska, NorthDakota, and South Dakota Colorado, Idaho, Montana, Utah, andWyoming Alaska New York Rhode Island

NewJersey and Pennsylvania Indiana and Ohio Kansas and Missouri Delaware, the District ofColumbia, Georgia, Maryland, North Carolina, South Carolina, Virginia, andWestVirginia Alabama, Kentucky, Mississippi, andTennessee Arkansas, Louisiana, and Oklahoma Arizona, Nevada, andNewMexico

Hawaii, Oregon, andWashington California

Texas Florida (a) DOE assumed that, using this criterion, mosthouseholds in the northern region would come from Connecticut, Maine, Massachusetts, New Hampshire, andVermont, while mosthouseholds in the southern region would come fromRhode Island. The same criterion applies to the other split divisions. (b) Notincluding California, which is included separately as one ofthe four large States. (c)NotincludingNew York, which is included separately as one ofthe four large States. (d) Not including Texas, which is included separately as one ofthe four large States. (e) NotincludingFlorida, which is included separately as one ofthe four large States.

11.3.2 

### Inputsto the Subgroup Analysis for Northern and SouthernHouseholds
DOE performedthe consumer subgroup analysis by analyzing the LCC and PBP of northern and southern households with the spreadsheet models used for the LCC analysis. DOE used the same inputs in the subgroup analysis as it used inthe LCC and PBP analysis (as described in Chapter 8) for non-weatherized gas furnace households considered to be northern or southernhouseholds.

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### Table 11.3.3 summarizes the weighted-average input values for the northern and southern

households analyzed in the consumer subgroup analysis and compares them to the weightedaverage input values for all households in RECS 2001 using non-weatherized gas furnaces. The northern households have, on average, higher energy use and lower energy prices than the southern households. Northern households have much greater average natural gas use than southern households.
Table 11.3

.3 Comparison of Input Values for All Households, Northern, and Southern

Households

Category All Households Northern Households Southern Households 

### >5000 >6000 <5000 <6000 Household Population Data Number of Household Records 1880 1067 463 814 1417 Sum of Weights (million households) 43.5 24.1 9.6 19.4 33.9 Percent of NWGF Household Population 100% 55.4% 22.0% 44.6% 78.0% Weighted-Average Annual Energy Use for Baseline Furnace Space-Heating Natural Gas Use (MMBtu) Space-Heating Electricity Use (kWh) 56.6 71.0 73.0 38.7 496 619 639 346 51.9 456 Weighted

-Average Natural Gas Prices Average Natural Gas Price ($/therm) Marginal Natural Gas Price ($/therm) 1.14 1.06 1.04 1.24 1.01 0.92 0.92 1.08 1.16 1.05 Weighted

-Average Electricity Prices Average Electricity Price (0/kWh) Marginal Electricity Price (0/kWh) 10.8 9.4 11.2 11.0 10.7 8.5 9.0 12.0 10.7 11.1



### 11.3.3 Results for Northern and Southern Households Tables 11.3.4 through 11.3.7 summarize the LCC results for the northern and southern households for non-weatherized gas furnaces, using the alternative definitions of northern and southern regions. These results can be compared to the overall results in Table 8.4.1 in Chapter 8. The tables provide the average or mean LCC and PBP, the LCC savings relative to the base case, and the percentage of consumers for whom the LCC will decrease compared to the base case forecast (positive benefit), those for whom the LCC will increase compared to the base case forecast (negative impact), and those for whom the LCC will not change because the specific design option is less efficient or the same as the base case forecast for that house (and therefore the standard has no impact). The northern and southern consumer subgroups (using 5,000 HDD criteria) differ significantly in terms of average LCC savings and consumer impacts (i.e., percentage of

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### Table 11.3.3 summarizes the weighted-average inputvalues for the northern and southern households analyzed in the consumer subgroup analysis and compares them to the weightedaverage inputvalues for all households in RECS 2001 using non-weatherized gas furnaces. The northern households have, on average, higher energy use and lower energyprices thanthe southernhouseholds. Northernhouseholds have much greater average natural gas use than southernhouseholds.


### Table 11.3.3 Comparison ofInputValues for All Households, Northern, and Southern Households

Northern Southern Category All Households Households Households 

### >5000 >6000 <5000 <6000 Household Population Data Number ofHousehold Records 1880 1067 463 814 1417 Sum ofWeights (million households) 43.5 24.1 9.6 19.4 33.9 Percent ofNWGF Household Population 100% 55.4% 22.0% 44.6% 78.0% 

### Weighted-AverageAnnual Energy Use for Baseline Furnace Space-HeatingNatural Gas Use (MMBtu) 56.6 71.0 73.0 38.7 51.9 Space-Heating ElectricityUse (kWh) 496 619 639 346 456 

### Weighted-AverageNatural Gas Prices AverageNatural Gas Price ($/thenn) 1.14 1.06 1.04 1.24 1.16 Marginal Natural Gas Price ($/thenn) 1.01 0.92 0.92 1.08 1.05 

### Weighted-Average Electricity Prices Average Electricity Price (¢/kWh) 10.8 9.4 11.2 11.0 10.7 Marginal Electricity Price (¢/kWh) 10.7 8.5 9.0 12.0 11.1



### 11.3.3 Results for Northern and SouthernHouseholds
Tables 11.3.4 through 11.3.7 summarize the LCC results for the northern and southern households for non-weatherized gas furnaces, using the alternative definitions ofnorthern and southernregions. Theseresults canbe compared to the overall results in Table 8.4.1 in Chapter 8. The tables provide the average ormeanLCC and PBP, the LCC savings relative to the base case, andthe percentage ofconsumers for whomthe LCC will decrease comparedto the base case forecast (positive benefit), those for whomthe LCCwill increase compared to the base case forecast (negative impact), andthose for whomthe LCC will not changebecause the specific design option is less efficient orthe same as the base case forecast for thathouse (and therefore the standardhas no impact).
The northern and southern consumer subgroups (using 5,000 HDD criteria) differ significantly interms ofaverage LCC savings and consumerimpacts (i.e., percentage of

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### consumers with net cost or benefit). For the 90 percent AFUE level, in the northern households

the average LCC savings is $178 and the percent of households with net cost (negative impact) is 23 percent, while the southern households have an average LCC cost of $82 and the percent of households with net cost is 55 percent. The higher LCC savings and lower economic impact in the northern households as compared to southern households is due to the much greater energy consumption in the north, which allows for more energy savings from higher furnace efficiency.
Table 11.3.4 Non-Weatherized Gas Furnaces : LCC and PBP Results for Northern

Life-Cycle Cost Life-Cycle Cost Savings Payback Period (years)" Design Option Average Average Households with Avera e Avera e by AFUE Installed Operating g LCC g Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,045 $13,098 $15,143 80% $2,054 $12,829 $14,883 $2 0% 99% 1% 0.6 0.7 80% Modulation $2,360 $12,890 $15,251 -$195 52% 47% 2% 40 73 (Two-Stage) 81% $2,128 $12,700 $14,828 $28 20% 47% 34% 9 14 8 1 % Modulation $2,434 $12,761 $15,195 -$169 49% 47% 4% 32 62 (Two-Stage) 90% $2,751 $11,740 $14,491 $178 23% 47% 31% 10 13 92% $2,930 $11,536 $14,466 $184 33% 34% 33% 12 15 92% Modulation $3,195 $11,634 $14,829 -$170 77% 2.6% 21% 18 35 (Two-Stage) 92%Modulation $3,239 $11,778 $15,016 -$353 83% 2.6% 14% 19 39 (Continuous) 96%Modulation $3,918 $11,404 $15,322 -$653 85% 2.6% 12% 30 60 (Continuous) 

### Households (greater than 5,000 HDD)

* "No impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. ** Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator. 

### consumers with net cost orbenefit). Forthe 90 percentAFUE level, in the northernhouseholds the average 

## Lee savings is $178 and the percent ofhouseholds with net cost (negative impact) is 23 percent, while the southern households have an average 

## Lee cost of$82 andthe percent of households with net cost is 55 percent. The higher

## Lee savings and lower economic impact in the northern households as comparedto southernhouseholds is due to the much greater energy consumptionin the north, which allows for more energy savings from higher furnace efficiency.


### Table 11.3.4 Non-Weatherized GasFurnaces: 

# Lee andPBP Results for Northern Households (greaterthan 5,000 HDD) Life-Cycle Cost Life-Cycle CostSavings PaybackPeriod (Years)** Design Option Average Average Households with Average Average byAFUE Installed Operating LCC Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,045 $13,098 $15,143 80% $2,054 $12,829 $14,883 $2 0% 99% 1% 0.6 0.7 80% Modulation $2,360 $12,890 $15,251 -$195 52% 47% 2% 40 73 (Two-Stage) 81% $2,128 $12,700 $14,828 $28 20% 47% 34% 9 14 81% Modulation $2,434 $12,761 $15,195 -$169 49% 47% 4% 32 62 (Two-Stage) 90% $2,751 $11,740 $14,491 $178 23% 47% 31% 10 13 92% $2,930 $11,536 $14,466 $184 33% 34% 33% 12 15 92% Modulation $3,195 $11,634 $14,829 -$170 77% 2.6% 21% 18 35 (Two-Stage) 92% Modulation $3,239 $11,778 $15,016 -$353 83% 2.6% 14% 19 39 (Continuous) 96% Modulation $3,918 $11,404 $15,322 -$653 85% 2.6% 12% 30 60 (Continuous) 

## * "No Impact" means thatthe base case forecast furnace assignedto the household has greater effiCIency than the level indicated, so the household is not affected. 

## ** Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably abetter indicator.

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### Table 11.3.5 Non-Weatherized Gas Furnaces : LCC and PBP Results for Southern

Life-Cycle Cost Life-Cycle Cost Savings Payback Period (Years)** Design Option Average Average Households with Avera e Avera e by AFUE Installed Operating g LCC g Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,021 $8,418 $10,439 80% $2,030 $8,255 $10,285 $2 0% 98% 2% 1.7 2.2 80% Modulation $2,331 $8,374 $10,706 -$322 76% 23% 1% 62 102 (Two-Stage) 81% $2,103 $8,176 $10,280 $1 40% 23% 37% 15 29 81% Modulation $2,405 $8,296 $10,701 -$330 77% .21% 2% 59 98 (Two-Stage) 90% $2,715 $7,629 $10,345 -$82 55% 21% 23% 18 26 92% $2,892 $7,505 $10,397 -$130 60% 17% 23% 20 28 92%Modulation $3,151 $7,657 $10,808 -$536 87% 1.4% 11% 30 61 (Two-Stage) 92% Modulation $3,194 $7,759 $10,953 -$679 90% 1.4% 9% 34 84 (Continuous) 96%Modulation $3,860 $7,529 $11,389 -$1,108 92% 1.4% 7% 44 101 (Continuous) 

### Households (less than 5,000 HDD

"No impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator. 

### Table 11.3.5 Non-Weatherized Gas Furnaces: LCC andPBP Results for Southern Households (less than 5,000 HDD) Life-Cycle Cost Life-Cycle CostSavings PaybackPeriod (Years)** Design Option Average Average Households with Average Average by AFUE Installed Operating LCC Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,021 $8,418 $10,439 80% $2,030 $8,255 $10,285 $2 0% 98% 2% l.7 2.2 80% Modulation $2,331 $8,374 $lO,706 -$322 76% 23% 1% 62 102 (Two-Stage) 81% $2,103 $8,176 $10,280 $1 40% 23% 37% 15 29 81% Modulation $2,405 $8,296 $10,701 -$330 77% 21% 2% 59 98 (Two-Stage) 90% $2,715 $7,629 $10,345 -$82 55% 21% 23% 18 26 92% $2,892 $7,505 $10,397 -$l30 60% 17% 23% 20 28 92% Modulation $3,151 $7,657 $10,808 -$536 87% 1.4% 11% 30 61 (Two-Stage) 92% Modulation $3,194 $7,759 $lO,953 -$679 90% 1.4% 9% 34 84 (Continuous) 96% Modulation $3,860 $7,529 $11,389 -$1,108 92% 1.4% 7% 44 101 (Continuous) 

## * "No impact" means thatthe base case forecast furnace assigned to the householdhas greaterefficiency than the level indicated, so the household is not affected. 

## ** Based on the payback calculation, a very small change in operating cost canresult in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably abetter indicator.

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### Using a 6,000 HDD criteria yields somewhat different results. For the 90 percent AFUE

level, in the northern households the average LCC savings is $212 and the percent of households with net cost is 22 percent, while in the southern households the average LCC savings is $5 and the percent of households with net cost is 42 percent.
Table 11.3.6 Non-Weatherized Gas Furnaces : LCC and PBP Results for Northern

Life-Cycle Cost Life-Cycle Cost Savings Payback Period (Years)** Design Option Average Average Households with Avera e Avera e by AFUE Installed Operating g LCC g Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,041 $13,451 $15,492 80% $2,050 $13,172 $15,222 $3 0% 98% 2% 0.7 0.7 80% Modulation $2,355 $13,231 $15,586 -$188 51% 47% 3% 36 68 (Two-Stage) 81% $2,124 $13,037 $15,161 $32 20% 47% 34% 9 14 8 1 % Modulation $2,429 $13,096 $15,525 -$160 48% 47% 5% 29 59 (Two-Stage) 90% $2,744 $12,035 $14,779 $212 22% 47% 31% 11 13 92% $2,923 $11,822 $14,745 $224 32% 35% 33% 12 15 92%Modulation $3,186 $11,917 $15,103 -$126 77% 2.4% 21% 19 35 (Two-Stage) 92% Modulation $3,230 $12,063 $15,293 -$311 82% 2.4% 16% 20 43 (Continuous) 96% Modulation $3,906 $11,676 $15,582 -$598 84% 2.4% 13% 32 61 (Continuous) 

### Households (greater than 6,000 HDD)

* "No impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. ** Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator. 

### Using a 6,000 HDD criteriayields somewhat differentresults. Forthe 90 percentAFUE level, in the northern households the average 

## Lee savings is $212 and the percent ofhouseholds with net cost is 22 percent, while in the southernhouseholds the average 

## Lee savings is $5 and the percent ofhouseholds with net cost is 42 percent. 

### Table 11.3.6 Non-Weatherized Gas Furnaces: LCC andPBPResults for Northern H h ld ( t th 6 000 HDD)

ouse 0 

### s 19rea er an 

# , Life-Cycle Cost Life-Cycle CostSavings PaybackPeriod (Years)** Design Option Average Average Households with by AFUE Installed Operating Average Average LCC Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,041 $13,451 $15,492 80% $2,050 $13,172 $15,222 $3 0% 98% 2% 0.7 0.7 80% Modulation $2,355 $13,231 $15,586 -$188 51% 47% 3% 36 68 (Two-Stage) 81% $2,124 $13,037 $15,161 $32 20% 47% 34% 9 14 81% Modulation $2,429 $13,096 $15,525 -$160 48% 47% 5% 29 59 (Two-Stage) 90% $2,744 $12,035 $14,779 $212 22% 47% 31% 11 13 92% $2,923 $11,822 $14,745 $224 32% 35% 33% 12 15 92% Modulation $3,186 $11,917 $15,103 -$126 77% 2.4% 21% 19 35 (Two-Stage) 92% Modulation $3,230 $12,063 $15,293 -$311 82% 2.4% 16% 20 43 (Continuous) 96% Modulation $3,906 $11,676 $15,582 -$598 84% 2.4% 13% 32 61 (Continuous) 

## * "No impact" means that the base case forecast furnace assIgned to the household has greater efficIency than the level indicated, so the household is not affected. 

## ** Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. Inthese cases, median is probably a better indicator.

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### Table 11.3.7 Non-Weatherized Gas Furnaces : LCC and PBP Results for Southern

Life-Cycle Cost Life-Cycle Cost Savings Payback Period (Years)** Design Option Average Average Households with Avera e Avera e by AFUE Installed Operating g LCC g Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,035 $10,223 $12,257 80% $2,044 $10,021 $12,065 $1 0% 99% 1% 1.6 2.0 80%Modulation $2,348 $10,115 $12,463 -$270 66% 33% 1% 53 87 (Two-Stage) 81% $2,117 $9,924 $12,041 $9 32% 33% 35% 13 24 81% Modulation $2,422 $10,019 $12,440 -$266 65% 32% 2% 46 84 (Two-Stage) 90% $2,735 $9,226 $11,962 $5 42% 32% 26% 15 21 92% $2,913 $9,073 $11,986 -$23 49% 24% 27% 16 23 92% Modulation $3,176 $9,203 $12,379 -$408 83% 2.1% 15% 24 49 (Two-Stage) 92% Modulation $3,219 $9,324 $12,543 -$568 87% 2.1% 10% 27 66 (Continuous) 96% Modulation $3,892 $9,041 $12,933 -$952 90% 2.1% 8% 37 84 (Continuous) 

### Households (less than 6,000 HOD

"No impact" means that the base case forecast furnace assigned to the household has greater efficiency than the level indicated, so the household is not affected. Based on the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skew the average payback. In these cases, median is probably a better indicator. 

### Table 11.3.7 Non-Weatherized Gas Furnaces: LCC andPBP Results for Southern Households (less than 6,000 HDD) Life-Cycle Cost Life-Cycle CostSavings PaybackPeriod (Years)** Design Option Average Average Households with by AFUE Installed Operating Average Average LCC Savings Net No Net Median Average Price Cost Cost Impact* Benefit 78% $2,035 $10,223 $12,257 80% $2,044 $10,021 $12,065 $1 0% 99% 1% 1.6 2.0 80% Modulation $2,348 $10,115 $12,463 -$270 66% 33% 1% 53 87 (Two-Stage) 81% $2,117 $9,924 $12,041 $9 32% 33% 35% 13 24 81% Modulation $2,422 $10,019 $12,440 -$266 65% 32% 2% 46 84 (Two-Stage) 90% $2,735 $9,226 $11,962 $5 42% 32% 26% 15 21 92% $2,913 $9,073 $11,986 -$23 49% 24% 27% 16 23 92% Modulation $3,176 $9,203 $12,379 -$408 83% 2.1% 15% 24 49 (Two-Stage) 92% Modulation $3,219 $9,324 $12,543 -$568 87% 2.1% 10% 27 66 (Continuous) 96% Modulation $3,892 $9,041 $12,933 -$952 90% 2.1% 8% 37 84 (Continuous) 

## * "No Impact" means that the base case forecast furnace assignedto the household has greaterefficiency than the level indicated, so the household is not affected. 

## ** Basedon the payback calculation, a very small change in operating cost can result in a few extremely large paybacks, which will skewthe average payback. In these cases, median is probably a better indicator.

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### REFERENCES U.S. Department of Energy - Energy Information Administration. Residential Energy Consumption Survey: Household Energy Consumption and Expenditures 2001. 2001. (Last accessed May 18, 2005.) <http://www.eia.doe.gov/emeu/recs/recs2001/publicuse2OOI.html> 

### REFERENCES
1. U.S. Department ofEnergy

- Energy InformationAdministration. ResidentialEnergy Consumption Survey: HouseholdEnergy Consumption andExpenditures 2001.2001. (Last accessedMay 18,2005.) <http://www.eia.doe.gov/emeu/recs/recs200l/publicuse200l.html>

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