ENERGY STAR® FOR WINDOWS, DOORS, AND SKYLIGHTS
COST AND ENERGY SAVINGS:
National, Regional, and City Estimates, Factoids, and Their Use
ENERGY STAR
INSIDE
Usage Guidelines	page 1
National Savings Estimates	1
Regional Savings Estimates	2
City Savings Estimates	4
•	Factoids	7
•	Methodology	9
For More Information	9
February 2005

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OVERVIEW The U.S. Department of Energy (DOE) is pleased
to provide partners with new cost and energy
savings estimates for use in marketing ENERGY
STAR qualified windows. Below you will find
annual national, regional, and local savings
estimates for choosing ENERGY STAR when
replacing single pane or double pane, clear
glass windows in existing construction or as an
alternative to double pane, clear glass windows
in new construction, as well as sample factoids
based on these estimates. These estimates
were calculated using RESFEN 3.11 with default
assumptions for a typical home, U.S. Census
2000 data, and August 2004 state average
utility rates.
Choosing to install ENERGY
STAR qualified windows
saves homeowners
money and energy nearly
everywhere in the U.S.
This document provides
the raw materials to best
communicate these savings
to buyers—cost and energy
savings estimates expressed
in dollar and energy terms
and related factoids.
USAGE GUIDELINES Partners who wish to use the official savings estimates and related factoids should:
•	Use the data and statements provided. Do not alter the meaning of the savings
estimates. Statements may be reworded if this rewording does not expand or
alter the meaning. Rewording must be done carefully as even slight alterations
can make a statement inaccurate. Do not round the numbers.
•	Use the savings range when provided (e.g. national savings). Do not cite a
single number or use "up to" terminology when a range is provided as it can be
misleading given the variation in the savings estimates from region to region.
•	Always cite the data source. Citations are provided below. Supplying
information about assumptions is recommended but not required.
•	Use the data for the promotion of residential windows only. The data only apply
to windows and should not be used for promoting doors or skylights.
NATIONAL
SAVINGS ESTIMATES Table 1 presents the national costsavings estimates for using ENERGY STAR
qualified windows underthree conditions: relative to single pane, relative to a
typical alternative (clear glass, double pane) in replacement, and relative to a
typical alternative (clear glass, double pane) in new construction.
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 1

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TABLE 1. National Savings Estimates

Relative to
Relative to Typical Alternative
Single Pane
Replacement New Construction
Official Savings
Statements:
Choose ENERGY
STAR® and save
$125-$340 a year
when replacing
single pane
windows
Choose ENERGY
STAR® and save
$20-$70 a year
over double
pane, clear glass
replacement
windows
Choose ENERGY
STAR® and save
$15-$65 a year
over double
pane, clear glass
windows in new
construction
REGIONAL
SAVINGS ESTIMATES
CITATION FOR NATIONAL SAVINGS ESTIMATES
U.S. Department of Energy (2005). www.energystar.gov/windows.
ASSUMPTIONS
Relative to Single Pane: Savings estimates based on population-weighted regional
average annual energy use for a 2,000 sq. ft., single story, detached house with 15%
glazing, gas heat and electric air conditioning. Estimates use August 2004 state average
utility rates. Actual savings will vary by climate region and home characteristics.
Relative to Typical Alternative: Savings estimates based on population-weighted
regional average annual energy use for a 2,000 sq. ft., single story, detached house
with 15% glazing, gas heat and electric air conditioning. Estimates use August 2004
state average utility rates. The typical alternative (clear glass, double pane) may not
be applicable to all jurisdictions due to mandatory building codes. Actual savings will
vary by climate region and home characteristics.
Regional cost and energy savings estimates have been calculated forthe eleven
modified census divisions shown in Figure 1.
FIGURE 1. Modified U.S. Census Divisions2
NORTHWEST
WEST NORTH
MOUNTAIN
CENTRAL
EAST NORTH
CENTRAL
ENGLAND
•	^ MIDDLE
*	ATLANTIC
SOUTH
ATLANTIC
FLORIDA
WEST SOUTH
EAST SOUTH
CENTRAL
CENTRAL
CALIFORNIA h
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 2

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Table 2 presents the regional cost ($) and energy (Btu3) savings estimates for using
ENERGY STAR qualified windows under three conditions: relative to single pane,
relative to a typical alternative (clear glass, double pane) in replacement, and
relative to a typical alternative (clear glass, double pane) in new construction.
TABLE 2. Regional Savings Estimates

Relative to
Relative to Typical Alternative

Single Pane
Replacement
New Construction
Official Savings
Statements:
Choose ENERGY
STAR® and save
[insert$ or Btu]
a year when
replacing single
pane windows
Choose ENERGY
STAR® and save
[insert$ or Btu]
a year over double
pane, clear glass
replacement
windows
Choose ENERGY
STAR® and save
[inserts or Btu]
a year over double
pane, clear glass
windows in new
construction
REGION
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
California
$125
9.9
$20
0.3
$15
0.4
East North Central
$270
24.8
$60
4.7
$55
4.5
East South Central
$260
18.9
$45
2.4
$40
2.4
Florida
$150
6.1
$60
2.3
$55
2.2
Middle Atlantic
$300
21.8
$70
3.9
$65
3.8
Mountain
$295
24.5
$50
2.9
$45
2.7
New England
$340
23.5
$65
3.9
$65
3.8
Northwest
$285
30.9
$35
3.6
$35
3.5
South Atlantic
$325
20.1
$45
2.2
$45
2.2
West North Central
$290
25.1
$65
4.8
$60
4.6
West South Central
$210
12.5
$65
2.2
$60
2.1
CITATION FOR REGIONAL SAVINGS ESTIMATES
U.S. Department of Energy (2005). www.energystar.gov/windows.
ASSUMPTIONS
Same assumptions as national savings estimates (page 2).
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 3

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CITY
SAVINGS ESTIMATES
Table 3 lists cost and energy savings estimates for 93 U.S. cities.
TABLE 3. City Savings Estimates4
Official Savings
Statements:
Relative to
Single Pane
Choose ENERGY
STAR® and save
[insert$ or Btu] a year
when replacing single
pane windows
Relative to Typical Alternative
Replacement New Construction
Choose ENERGY
STAR® and save
[insert$ or Btu] a
year over double
pane, clear glass
replacement windows
Choose ENERGY
STAR® and save
[insertS or Btu] a year
over double pane,
clear glass windows
in new construction
CITY
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
AK, Anchorage
$270
54
$40
7.6
$40
7.8
AK, Fairbanks
$350
69
$50
9.4
$60
11.3
AL, Birmingham
$240
14.8
$35
1.8
$35
1.8
AL, Mobile
$120
6.2
$35
0.8
$35
0.7
AR, Little Rock
$275
18
$40
2.2
$45
2.3
AZ, Phoenix
$275
12.9
$70
2.7
$80
3.1
AZ, Flagstaff
$410
28.6
$20
1.1
$20
1.2
AZ, Tucson
$245
12.7
$50
1.9
$60
2.2
CA, Fresno
$225
15.1
$50
1.9
$60
2.1
CA, Los Angeles 5-6
$70
5.9
$5
-0.1
$10
-0.2
CA, Red Bluff
$265
19
$55
2.4
$65
2.8
CA, San Diego
$70
4.8
$10
0.2
$15
0.2
CA, San Francisco
$120
12.8
($5)
-0.6
($10)
-1.2
CA, Areata
$160
17.6
$0
-0.3
($5)
-0.6
CA, Bakersfield
$215
12.7
$50
1.5
$60
2.0
CA, Daggett
$255
13.3
$60
1.6
$70
1.8
CA, Sacramento
$195
15.1
$35
1.4
$40
1.5
CO, Denver
$305
30.2
$35
2.7
$40
2.8
CO, Grand Junction
$295
27.5
$40
2.8
$45
3.0
CT, Hartford
$365
23.3
$75
4.0
$80
4.3
DC, Washington
$405
27.5
$55
3.1
$60
3.3
DE, Wilmington
$440
28.1
$55
3.1
$60
3.2
FL, Jacksonville
$150
6.3
$50
1.6
$53
1.5
FL, Miami
$165
6.3
$115
4.4
$130
4.8
FL, Daytona Beach
$135
5.5
$65
2.2
$70
2.3
FL, Tallahassee
$145
6.1
$40
1.1
$40
1.0
FL, Tampa
$155
6.2
$85
2.9
$90
3.1
GA, Atlanta
$295
16.9
$40
1.9
$40
2.0
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 4

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CITY
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
GA, Savannah
$225
12.3
$40
1.7
$40
1.9
IA, Des Moines
$320
25
$70
4.6
$70
4.8
ID, Boise
$300
31.7
$35
3.4
$40
3.6
IL, Chicago
$285
25.1
$60
4.7
$65
5.0
IL, Springfield
$275
23.2
$60
4.3
$65
4.5
IN, Indianapolis
$250
21.9
$55
4.0
$55
4.2
KS, Wichita
$265
20
$55
3.4
$60
3.6
KY, Lexington
$355
26.8
$50
3.4
$50
3.4
KY, Louisville
$320
24
$45
3.1
$45
3.1
LA, Lake Charles
$140
7.5
$55
1.7
$60
1.7
LA, New Orleans
$120
6.2
$50
1.5
$55
1.4
LA, Shreveport
$210
13.8
$40
2.0
$45
2.1
MA, Boston
$335
23
$60
3.6
$60
3.6
MD, Baltimore
$435
27.1
$50
2.9
$55
3.0
ME, Portland
$320
24.9
$55
3.7
$55
3.6
Ml, Detroit
$240
26
$50
4.7
$50
4.9
Ml, Grand Rapids
$250
27.4
$55
5.2
$55
5.4
Ml, Houghton
$280
31
$60
5.9
$55
5.9
MN, Minneapolis
$310
29.9
$65
5.6
$70
5.8
MN, Duluth
$370
37
$75
7.0
$70
6.7
MO, Kansas City
$265
20.5
$60
3.8
$60
4.0
MO, St. Louis
$265
20.5
$60
3.8
$60
4.0
MS, Jackson
$205
14.7
$40
2.0
$40
2.1
MT, Great Falls
$440
44.2
$55
5.2
$60
5.2
MT, Billings
$425
41.8
$55
4.7
$55
4.8
NC, Raleigh
$280
18.8
$40
2.1
$40
1.9
ND, Bismarck
$300
32.1
$60
6.0
$65
6.1
NE, Omaha
$245
23.6
$55
4.4
$55
4.6
NH, Concord
$345
25
$70
4.2
$70
4.3
NJ, Atlantic City
$240
18.6
$50
2.8
$50
2.7
NM, Albuquerque
$250
20.2
$30
1.4
$35
1.5
NV, Las Vegas
$260
15
$55
1.7
$60
2.0
NV, Reno
$275
23.5
$30
1.7
$35
1.8
NY, Buffalo
$365
26.7
$80
5.2
$85
5.3
NY, New York
$290
20
$65
3.3
$65
3.4
NY, Albany
$355
25.7
$80
4.8
$80
4.9
OH, Dayton
$260
22.9
$55
4.1
$60
4.4
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use	PAGE 5

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CITY
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
Utility
Dollars
Btu
(millions)
0H, Cleveland
$275
24
$60
4.7
$60
4.8
OK, Oklahoma City
$290
22.2
$40
2.4
$40
2.4
OR, Medford
$270
23.6
$40
3.0
$40
2.9
OR, Portland
$265
24.6
$35
2.9
$35
2.7
PA, Philadelphia
$285
19.6
$60
3.3
$60
3.5
PA, Pittsburgh
$325
22.7
$70
4.3
$75
4.6
PA, Williamsport
$320
22.3
$65
4.1
$70
4.2
Rl, Providence
$310
22.5
$55
3.4
$60
3.5
SC, Charleston
$210
13.3
$35
1.6
$35
1.5
SC, Greenville
$250
16.9
$35
1.9
$35
1.7
SD, Pierre
$305
27.9
$60
4.9
$65
5.1
TN, Memphis
$235
17.8
$40
2.3
$40
2.1
TN, Nashville
$280
22.5
$45
3.0
$45
2.9
TX, Brownsville
$185
7.6
$110
3.7
$120
4.1
TX, El Paso
$230
13.9
$40
1.5
$50
1.7
TX, Fort Worth
$245
14.9
$50
1.9
$55
2.1
TX, San Antonio
$170
7.9
$80
2.0
$85
2.2
TX, Houston
$160
7.5
$75
2.2
$85
2.3
TX, Lubbock
$280
19.8
$40
1.8
$40
1.9
UT, Salt Lake City
$275
29.7
$40
3.3
$45
3.5
UT, Cedar City
$250
27.8
$30
2.3
$30
2.4
VA, Richmond
$385
21.7
$45
2.2
$50
2.3
VT, Burlington
$330
28.2
$70
5.2
$70
5.2
WA, Seattle
$355
27.6
$20
2.9
$30
2.9
WA, Spokane
$350
37.5
$45
4.3
$45
4.4
Wl, Madison
$295
27.4
$60
5.0
$65
5.1
WV, Charleston
$290
24.2
$35
2.7
$40
3.1
WY, Cheyenne
$340
41.4
$40
3.7
$40
3.7
CITATION FOR CITY SAVINGS ESTIMATES
U.S. Department of Energy (2005). www.energystar.gov/windows.
ASSUMPTIONS
Relative to Single Pane: Savings estimates based on average annual energy use for a 2,000
sq. ft., single story, detached house with 15% glazing, gas heat and electric air conditioning.
Estimates use state average utility rates. Actual savings will vary by home characteristics.
Relative to Typical Alternative: Savings estimates based on average annual energy use for a 2,000 sq.
ft., single story, detached house with 15% glazing, gas heat and electric air conditioning. Estimates
use state average utility rates. The typical alternative (clear glass, double pane) may not be applicable
to all jurisdictions due to mandatory building codes. Actual savings will vary by home characteristics.
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 6

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FACTOIDS For partners who prefer factoids, DOE has created a set of sample factoids (Figure 2)
and a factoid generator for a common set of factoids (Table 4).
FIGURE 2. Cost and Energy Factoids for Replacing Single Pane with
ENERGY STAR Qualified Windows in Select Cities
Replacing single pane windows with ENERGY STAR® qualified windows in the
typical home saves each year:
In Seattle, enough energy In Chicago, enough	In Boston, enough money
to brew a lifetime's worth money to take 14 friends to pick up the paper and
of coffee for 18 people7	to see the Cubs8	commute on the T for nearly
six months9

In San Francisco, I	jAr
enough money to I ¦	In Philadelphia,
cheese steaks10
In Phoenix, enough I	hHF
money for three V/
rounds at a top [	/	~		
rated golf course14 |	/	^	In Atlanta, enough
			energy for a year
In Denver, enough	^	and a ha,fs worth
money to outfit a	In Miami, enough	0f hot showers for
family of six with ski energy to keep a	g famj| Qf f(jurll
hats and gloves13 refrigerator full of
beverages frosty for
more than four years12
CITATION FOR FACTOIDS
U.S. Department of Energy (2005). www.energystar.gov/windows.
ASSUMPTIONS
Same assumptions as national, regional, or city savings estimates (above) plus any
additional assumptions used in the factoid, as shown in the Figure 2 end notes.
GENERATE YOUR OWN FACTOIDS
Follow the directions in Table 4 to generate your own factoids using the national,
regional or city savings estimates in Tables 1,2, and 3.
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 7

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TABLE 4. Factoid Generator
1.
Choose Condition
2.
Choose Factoid
3.
Calculate
4.
Add Citation
Replacing single pane
windows with ENERGY
...Enough money to
take	friends to see
[sporting event]
Utility dollar savings
from Tables 1, 2, 3
¦r [cost per ticket]
See citation for
Chicago in Figure 2
STAR® qualified
windows in the typical
home will save each
...Enough energy
to brew	cups
of coffee
Million Btu savings
from Tables 1, 2, 3
¦r 70 Btu
See citation for
Seattle in Figure 2
year....
Choosing ENERGY
STAR® qualified
windows over double
pane, clear glass when
replacing windows in
the typical home will
save each year...
...Enough energy to
keep a refrigerator
full of beverages
deliciously frosty
for	(years)
Million Btu savings
from Tables 1, 2, 3
¦r 1.5 million Btu
See citation for
Miami in Figure 2
...Enough energy for
	hot showers
Million Btu savings
from Tables 1, 2, 3
¦=¦11,070 Btu
See citation for
Atlanta in Figure 2
...Enough money to
buy	 [climate or
region appropriate
apparel or object]
Utility dollar savings
from Tables 1, 2, 3
¦r [cost of apparel
or object]
See citation for
Denver in Figure 2
Choosing ENERGY
STAR® qualified
windows over double
...Enough money to
enjoy	[ice cream
cones, hot cocoas, or
local treats]
Utility dollar savings
from Tables 1, 2, 3
¦r [cost of treat]
See citation for
Philadelphia in
Figure 2
pane, clear glass when
installing windows in
new construction in the
...Enough money to
play	rounds of golf
at [local course]
Utility dollar savings
from Tables 1, 2, 3
¦r [cost of round]
See citation for
Phoenix in Figure 2
typical home will save
each year...
...Enough money
to commute for
	(months)
Utility dollar savings
from Tables 1, 2, 3
¦r [average cost of
month's commute]
See citation for
Boston in Figure 2

...Enough money to
take a	day trip to
[exotic, warm, snowy
place or national park]
Utility dollar savings
from Tables 1, 2, 3
¦r [cost of trip]
See citation for
San Francisco in
Figure 2
Note: Be careful to follow these guidelines when using and generating factoids. Check
state and local building codes to ensure that double pane, clear glass windows are code
compliant and a legitimate alternative in that jurisdiction.
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 8

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METHODOLOGY The cost and energy savings estimates have as their base cost and energy
calculations performed by Lawrence Berkeley National Laboratory (LBNL) using
RESFEN 3.1 for a typical home in 93 U.S. cities. RESFEN, uses a DOE 2.1E calculation
engine and is the standard software program used for calculating the impact of
windows on heating and cooling costs for residential new construction or existing
housing stock. The typical home is defined as the RESFEN default home—a 2,000
square foot, single story, detached house with 300 square feet of window area
(15% of floor area), gas heat and electric air conditioning with RESFEN default
operational assumptions.16
Representative windows were selected from the RESFEN window library. For
ENERGY STAR qualified windows, types were selected for each city based on
the city's ENERGY STAR climate zone (Northern, North/Central, South/Central,
Southern). For single pane windows, types from the library closest to the dominant
type reported in the Energy Information Administration (EIA) 1997 Residential Energy
Consumption Survey (RECS 97) were selected—wood/vinyl frame for the Northeast
and Midwest census regions and aluminum frame for the West and South census
regions. For typical alternative windows, double pane, clear glass windows were
selected from the library with wood/vinyl frames for the Northern, North/Central,
and South/Central climate zones and aluminum frames for the Southern climate
zone. Where more than one library window qualified, the window that generated the
lowest (most conservative) savings estimates was selected.
Regional population-weighted savings estimates were created by first setting
performance for each U.S. county equal to the performance of the nearest RESFEN
city with a similar climate as defined by the climate zones in the Residential
International Conservation Code (RICC) code change proposal. ENERGY STAR climate
zones are based on RICC climate zones and the RICC code change proposal was
adopted into the 2004 Supplement to the 2003 International Energy Conservation Code.
U.S. Census 2000 county level population data were then used in combination with this
data setto calculate regional population-weighted averages. All calculations used
August 2004 EIA electric and gas utility prices for the corresponding state.
Hawaii was excluded from this analysis as RESFEN operational assumptions applied
in the base data set diverge significantly from the norm in Hawaii and generated
unrealistic savings estimates. Cost savings were rounded to the nearest multiple
of five and energy savings were rounded to the nearest 100,000 Btu to reflect their
characterization as estimates.
FOR MORE For more information on cost and energy savings from ENERGY STAR qualified
INFORMATION windows, visit the ENERGY STAR Web site, www.energystar.gov/windows, or
email windows@energystar.gov.
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
PAGE 9

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END NOTES
1A software program developed by Lawrence Berkeley National Laboratory for calculating the heating and cooling impacts of
windows in residential buildings for climates throughout the U.S. using a version of the DOE 2.1E building energy calculation
engine (http://windows.lbl.gov/software/resfen/default.htm).
2The American Architectural Manufacturers Association (AAMA) and Window and Door Manufacturers Association (WDMA)
industry market studies classify geographical data by modified U.S. census divisions; that organizational scheme is maintained
here with the exception of Hawaii (see Methodology).
3 Btu savings account for home heating and cooling savings, based on gas heat and electric air conditioning.
4These cities were included in the data set provided by Lawrence Berkeley National Laboratory.
5	Anomalies such as negative savings (costs) occur when the cooling energy savings from ENERGY STAR qualified windows are
less than the heating energy penalty, resulting in slightly greater average energy use than double clear windows.
6	Negative energy savings (increased energy use) and positive dollar savings occur simultaneously because electric cooling
cD
of electricity outweigh the increased heating costs leading to overall monetary savings.
Seattle energy savings relative to single pane = 28 million Btu, based on average annual energy use for a 2,000 sq. ft., single
stD
savings will vary by home characteristics. Energy to brew one cup of coffee = 70 Btu.
Chicago cost savings relative to single pane = $285, based on average annual energy use for a 2,000 sq. ft., single story,
detached house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual
savings will vary by home characteristics. Cubs ticket = $19.
Boston cost savings relative to single pane = $335, based on average annual energy use for a 2,000 sq. ft., single story, detached
housD
by home characteristics. T rail = $1,25/trip, newspaper = $0.35.
Philadelphia cost savings relative to single pane = $285, based on average annual energy use for a 2,000 sq. ft., single story,
detached house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual
savings will vary by home characteristics. Cheese steak sandwich = $6.
Atlanta energy savings relative to single pane = 17 million Btu, based on average annual energy use for a 2,000 sq. ft., single story,
detached house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual savings will
vary by home characteristics. Gas water heating, shower = 8.2 minutes, water flow = 2.2 gpm,0.67 showers/day.
Miami energy savings relative to single pane = 6.3 million Btu, based on average annual energy use for a 2,000 sq. ft., single story,
detached house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual savings
will vary by home characteristics. Average ENERGY STAR qualified standard refrigerator = 442 kWh/year.
Denver cost savings relative to single pane = $305, based on average annual energy use for a 2,000 sq. ft., single story, detached
house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual savings will vary by
home characteristics. Adult ski hat = $20, adult ski gloves = $55, youth ski hat = $15, youth ski gloves = $20.
Phoenix cost savings relative to single pane = $275, based on average annual energy use for a 2,000 sq. ft., single story, detached
house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual savings will vary by home
characteristics. Golf (in season) = $90.
San Francisco cost savings relative to single pane = $120, based on average annual energy use for a 2,000 sq. ft., single story, detached
house with 15% glazing, gas heat and electric air conditioning. Estimates use state average utility rates. Actual savings will vary by home
characteristics. Park entrance fee = $20. Camping = $18/night.
16Modeling assumptions are described in the RESFEN 3.1 Manual (http://windows.lbl.gov/software/resfen/resfen31.pdf).
COST & ENERGY SAVINGS: National, Regional, and City Estimates, Factoids, and Their Use
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