Energy Savings by Retrofitting Multi-Unit Residential ......in the Toronto Area 30 year design life...
Transcript of Energy Savings by Retrofitting Multi-Unit Residential ......in the Toronto Area 30 year design life...
Energy Savings by Retrofitting Multi-Unit Residential Buildings:
Case Studies
Marianne Touchie, Kim Pressnail & Ekaterina Tzekova University of Toronto
BEST 3, Atlanta, Georgia April 3rd, 2012
• Energy use in MURBs • Study Methodology • Assumptions • Case Studies: • Conclusions and Lessons Learned
Outline
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Rental Properties Condominium Properties
MURBs in Toronto, Canada
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MURB Housing starts in the Toronto Area
30 year design life
Housing Stock
Residential GHG Emissions
30%
40% 1950
1960
1970
1980
1990
2000
28,200
15,900
Figure Adapted from T. Kesik and I. Saleff. 2009. Tower renewal guidelines. University of Toronto.
Methodology
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• Building Owner/Manager Interviews
• Pre and Post-Retrofit Energy Consumption Analysis
• Weather normalization
• Energy Cost Savings
• Financial Performance of Retrofit Measures
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$0.50
$1.00
$1.50
$2.00
$2.50
$0.00
$0.10
$0.20
$0.30
$0.40
$0.50
2003
2004
2005
2006
2007
2008
2009
2010
Historical Utility Costs
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Cost
of W
ater
and
Was
tew
ater
/m3
Cost
of E
lect
ricity
/kW
h an
d N
atur
al G
as/m
3
Electricity
Natural Gas
Water Sources for Figure: City of Toronto. 2010. http://www.toronto.ca/utilitybill/water_rates.htm; E Ontario Energy Board 2010 http://www.ontarioenergyboard.ca/OEB/Consumers/Electricity/Electricity+Prices; Ontario Energy Board. 2010 http://www.oeb.gov.on.ca/OEB/Consumers/Natural+Gas/Natural+Gas+Rates/Natural+Gas+Rates+-+Historical;
Projected Utility Costs
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$-
$5
$10
$15
$20
$25
$30
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Aver
age
Util
ity C
ost p
er m
2
Electricity
Natural Gas
Water
Pre-Retrofit Condition:
32 suites Built in 1930’s High maintenance costs Frequent equipment breakdowns
Case Study 1 (Rental)
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Retrofit Strategy:
Windows
Attic insulation
Boiler controls and steam traps
Common area lighting
Faucets, showers, toilets
Case Study 1 (Rental)
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Actual Performance
Total Project Cost $74,200
Tonnes CO2e avoided/annum 46
Simple Payback 6.5 years
IRR over 10 years 10%
Net Present Value (4% Discount Rate)
$27,000
Case Study 1 (Rental)
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0
15,000
30,000
45,000
60,000
Nat
ural
Gas
Use
(m3 )
0
1,000
2,000
3,000
4,000
Wat
er U
se (m
3 )
50% 40%
Pre-Retrofit Condition:
128 suites Built in 1970 Roof reaching end of life Original, single-glazed windows
Case Study 2 (Rental)
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Retrofit Strategy:
Improved building envelope (replace windows, balcony doors and roof)
Reduced reliance on fossil fuels (install a solar thermal hot water system)
Case Study 2 (Rental)
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Case Study 2 (Rental)
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0
100,000
200,000
300,000
400,000
500,000
2007 2008 2009 2010 2011*
Annu
al N
atur
al G
as U
se (m
3 )
Projected Natural Gas Actual Natural Gas
21%
Actual Performance Total Project Cost (after incentives) $568,000
Tonnes CO2e avoided/annum 160
Payback based on energy cost savings 16 years
Payback based on energy cost savings and increased rental income
3 years
Pre-Retrofit Condition:
210 suites Built in 1974 Excessive energy bills Wanted to avoid borrowing costs
Case Study 3 (Condominium)
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Retrofit Strategy:
Boiler Replacement Air Handling Unit (AHU) Retrofit Toilet Replacement Chiller Replacement
Case Study 3 (Condominium)
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Actual Performance
Total Project Cost $678,000
Tonnes CO2e avoided/annum 277
Simple Payback 4 years
Net Present Value $267,000
Case Study 3 (Condominium)
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0
200,000
400,000
600,000
Nat
ural
Gas
Use
(m3 )
28%
0
30,000
60,000
90,000
Wat
er U
se (m
3)
29%
Pre-Retrofit Condition:
116 suite Occupied in 2001 Investigation into solar energy led to discovery of other energy savings measures
Case Study 4 (Condominium)
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Retrofit Strategy: Lighting Retrofit CO Monitor Installation Boiler Replacement Installation of Variable Frequency Drive on Make-Up Air Unit
Case Study 4 (Condominium)
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Case Study 4 (Condominium)
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Actual Performance Total Project Cost (after incentives) $146,000
Tonnes CO2e avoided/annum 153
Simple Payback 2.4 years
IRR over 10 years 45%
Net Present Value $260,000
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400,000
800,000
1,200,000
1,600,000
Elec
tric
ity U
se (k
Wh)
12%
-
100,000
200,000
300,000
400,000
Nat
ural
Gas
Use
(m3 )
31%
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$83/tCO2
Summary of Retrofit Impacts
Boiler Controls/Wndw Replace/Attic
insulation (Bldg 1) Boiler Replacement
(Bldg 3)
Boiler Replacement (Bldg 4)
Lighting Retrofit (Bldg 1)
Lighting/ Exhaust /MAU
(Bldg 4)
Water Fixture Replacement (Bldg 1)
Toilet Replacement (Bldg 3)
Chiller upgrade (Bldg 3)
$-
$200
$400
$600
$800
$1,000
$1,200
0 2 4 6 8 10
Cost
of A
void
ed G
HG E
miss
ions
($/t
CO2 e
)
Simple Payback (yrs)
Planning:
Whole Building Approach Establish Baseline Utility Use Enhance Existing Maintenance Projects Quick Payback + Longer Payback Items http://www.stlucieco.gov/planning/planning.htm
Lessons Learned
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Financing:
Energy Conservation Incentives
Financial Analysis Tools Construction:
COMMUNICATION! Operations:
Ongoing control
hwww.mediatonet.com/Financing.html, www.reggin.ca/hvac.htm, www.afmcontrols.com/, ableandbakerdesign.blogspot.com/2009/09/1968-airstream-retrofit-window.html
Lessons Learned
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For more information…
Energy Retrofit Case Studies on the TowerWise Website towerwise.ca/case_studies
Marianne Touchie
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