Thermal System and Net-Zero-Carbon Least-Cost Design Optimization of New Detached Houses in Canada
<p>LCC vs. GHG optimization analysis representation.</p> "> Figure 2
<p>Optimization schedule by location and thermal system type; NZC (net-zero carbon) is the overall least LCC all-electric design + PV. In this figure, VN stands for Vancouver, ED for Edmonton, TO for Toronto, ML for Montreal, HX for Halifax.</p> "> Figure 3
<p>Model geometry-clockwise from top left: north, south, west, east (green = conditioned volume).</p> "> Figure 4
<p>Reference model SHDI and EUI values.</p> "> Figure 5
<p>Reference model EUI Breakdown by end-use for thermal-system-specific Toronto baseline models (hatching = natural gas, solid = electricity).</p> "> Figure 6
<p>Toronto MSHP design cash flows (chart excludes residual value: <span>$</span>79,938 in year 30, i.e., a negative cost).</p> "> Figure 7
<p>Gas-TO optimization plot with exterior wall insulation sensitivity frontiers.</p> "> Figure 8
<p>The optimal design arranged from left to right and top to bottom, starting with Vancouver, followed by Edmonton, Toronto, Montreal, and finally, Halifax.</p> "> Figure 9
<p>Edmonton NZE optimization results with PV systems.</p> "> Figure 10
<p>Initial cost optimal designs—Toronto (“fixed” includes lighting, appliances, ceiling fans, doors, eaves, and thermal mass).</p> "> Figure 11
<p>Annual energy use by end-use—Toronto (hatched = natural gas, solid = electricity).</p> "> Figure 12
<p>Annual energy costs of optimal models—Toronto (E = electricity, G = natural gas).</p> "> Figure 13
<p>Annual GHG emissions by fuel type—Toronto.</p> "> Figure 14
<p>The SHDI of optimal Toronto design enclosures; the orange line represents the climate-specific North American Passive House Standard Target [<a href="#B32-buildings-14-02870" class="html-bibr">32</a>].</p> "> Figure 15
<p>Hourly heating delivered by the MSHP—Toronto.</p> "> Figure 16
<p>Annual hourly electric load profile of heat pump and whole building for MSHP—Toronto design.</p> "> Figure 17
<p>January day electric load profile—Toronto.</p> "> Figure 18
<p>Energy use versus GHG emissions—Toronto (orange = MSHP design variants, blue = gas design variants).</p> "> Figure 19
<p>Energy use versus GHG emissions—Edmonton.</p> ">
Abstract
:1. Introduction
2. Methodology
- Determine the life cycle cost (LCC) and GHG emissions of least-cost electric and zero-carbon building designs using fundamental economics, building physics, and the best available heating technologies, without subsidies or a carbon price.
- Analyze the correlation between heating system type/efficiency and optimal enclosure design (SHDI). Also, investigate the relationship between energy standard performance metrics (SHDI and EUI), homebuyer/ratepayer primary concern metrics, and electricity emission factors (EFs).
2.1. Building Energy Performance Optimization
2.2. Thermal System Optimization
2.3. Building Enclosure Thermal Performance
2.4. Electrification of Heating
2.5. Onsite Renewable Energy Generation
3. Building Energy Model
3.1. Model House Description
3.2. Thermal System Models
3.2.1. Modelled Thermal Systems Summary
3.2.2. Thermal Envelope Performance (SHDI)
3.2.3. Purchased Energy Consumption (EUI)
4. LCC Optimization
4.1. Location, Climate, and Emissions Factors
4.2. City Cost Index (CCI)
4.3. Purchased Energy Prices
4.4. Financial Model
4.4.1. Capital Costs
4.4.2. Mortgage
4.4.3. Economic Parameters
4.4.4. Cash Flows and LCC
4.5. Design Input Options
5. Optimization Results and Discussion
5.1. Gas Model Optimization
5.2. LCCs versus GHG Optimization Results
5.2.1. Results Summary
5.2.2. NZC Models
5.3. Initial Cost and Design
5.4. Operational Energy, Cost, and Emissions
5.4.1. Purchased Energy Use
5.4.2. Enclosure Thermal Performance
5.4.3. Mechanical Heating
5.4.4. EUI versus GHGI Relationship
6. Conclusions and Recommendations
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
Appendix A. Reference Model Input Parameters (Toronto)
Group | Category | Parameter |
Building | Orientation | North (front of house) |
Neighbors | Suburban | |
Walls | Wood Stud * | R-21 fiberglass batt, 2 × 6, 24 in o.c., 1/2” OSB, air gap (R-effective: 17.7) |
Wall Sheathing | None | |
Exterior Finish | Vinyl, light coloured | |
Interzonal Walls | R-21 fiberglass batt, 2 × 6, 24 in o.c. (R-effective: 16.8) | |
Ceilings/Roofs | Unfinished Attic * | Ceiling R-38 fiberglass, vented (R-effective: 39.6) |
Roof Material | Asphalt shingles, medium | |
Radiant Barrier | None | |
Foundation/Floors | Unfinished Basement * | Whole wall R-18 polyiso (R-effective: 19.3) |
Interzonal Floor | R-38 fiberglass (R-effective: 28.7) | |
Carpet | 20% carpet | |
Thermal Mass | Floor Mass | Wood surface |
Exterior Wall Mass | 1/2 in. drywall | |
Partition Wall Mass | 1/2 in. drywall | |
Ceiling Mass | 1/2 in. drywall | |
Windows and Doors | Window Areas | Front: 18%, back: 23%, left: 10%, right: 10% |
Windows * | U-value 0.32, low-e, double, insulated, air, SHGC 0.56 | |
Interior Shading | Summer = 0.5 unshaded, winter = 0.95 unshaded | |
Door Area | 3.72 m2 (40 ft2) | |
Doors | Fiberglass, U-value 0.2 | |
Eaves | 0.61 m (2′) | |
Overhangs | None | |
Airflow | Air Leakage | 2.5 ACH50 |
Mechanical Ventilation | HRV, SRE 70% | |
Natural Ventilation | HRV economizer year-round, 24 h, 7 days/wk. | |
Space Conditioning | Central Air Conditioner | SEER 15, single stage |
Furnace | Gas, 80% AFUE | |
Ducts | 7.5% air leakage, uninsulated | |
Ceiling Fan | Standard efficiency, 50% Coverage | |
Space Conditioning Schedules | Cooling Set Point | 25 °C (77 °F) |
Heating Set Point | 21.1 °C (70 °F) | |
Water Heating | Water Heater | Gas standard, energy factor 0.59 |
Distribution | Uninsulated, trunk branch, PEX | |
Lighting | Lighting | 100% LED |
Appliances and Fixtures | Refrigerator | Top freezer, energy factor = 17.6 |
Cooking Range | Electric | |
Dishwasher | 318 Rated kWh | |
Clothes Washer | EnergyStar | |
Clothes Dryer | Electric | |
Hot Water Fixtures | Standard | |
Miscellaneous | Plug Loads | Standard |
(grey = optimization options, green = value is reset for optimization); * may vary by location. |
Appendix B. Reference Model Parameter Sources
Design Parameter | Reference Design Source | Notes |
Geometry | Custom | Detached |
Basement | Custom | Unfinished |
Orientation | Custom | South facing |
Nearby obstructions | Custom | Suburban |
* Envelope thermal resistance | NBC 9.36 | |
Exterior finish | BA B10 | |
Roof material | BA B10 | |
Window/door area distribution | NBC 9.36 | |
* Windows | NBC 9.36 | |
Doors | BA B10 | |
Thermal mass | BA B10 | |
Airtightness | NBC 9.36 | |
HRV/ERV | Custom | SRE 70% |
Central AC | NBC 9.36 | All locations |
Furnace | NBC 9.36 | |
Ducts | Custom | Uninsulated, tight |
Ceiling fan | Custom | Standard efficiency |
Water heater | NBC 9.36 | |
DHW distribution | NBC 9.36 | No insulation |
DHW consumption (equipment) | BA B10 | |
Lighting | Custom/BA Protocol | 100% LED |
Large appliances | BA B10 * | Washer—ENERGY STAR |
MEL | BA B10 | |
Control | ||
Interior shading | Custom | High-latitude, cold climate |
Natural ventilation | Custom | HRV Economizer |
Mechanical ventilation | ASHRAE 62.2 | 2013 |
Conditioning setpoints | NBC 9.36 | |
DHW setpoint | BA Protocol | |
DHW consumption (behaviour) | BA B10 | |
Schedules | BA Protocol | |
* Reference design varies by location. |
References
- Canada Mortgage and Housing Corporation. Housing Information Monthly. Publications and Reports 2018. Available online: https://www.cmhc-schl.gc.ca/professionals/housing-markets-data-and-research/market-reports/housing-market (accessed on 11 July 2016).
- Canada Mortgage and Housing Corporation. CMHC. New Housing Construction Activity. January 2018. Available online: https://www03.cmhc-schl.gc.ca/hmip-pimh/en#Profile/1/1/Canada (accessed on 11 July 2016).
- Greenhouse Gas Sources and Sinks in Canada. National Inventory Report 1990–2016: Environment and Climate Change Canada. Available online: https://www.canada.ca/en/environment-climate-change/services/climate-change/greenhouse-gas-emissions/sources-sinks-executive-summary-2023.html (accessed on 29 April 2024).
- Dembo, A.; Fung, A.S. Review and economic feasibility study of the currently practiced new housing constructions in Ontario. ASHRAE Trans. 2012, 118, 409–426. [Google Scholar]
- Dembo, A.; Khaddad, F.; Fung, A. Least-cost upgrade solutions to achieve improved energy efficiency standards for residential new housing in Canada. ASHRAE Trans. 2013, 119, 1–17. Available online: https://www.ashrae.org/file%20library/technical%20resources/ashrae%20transactions%20and%20conferences%20programs/2013-dallas-transactions-toc.pdf (accessed on 11 July 2016).
- Omrany, H.; Chang, R.; Soebarto, V.; Zhang, Y.; Ghaffarianhoseini, A.; Zuo, J. A bibliometric review of net zero energy building research 1995–2022. Energy Build. 2022, 262, 111996. [Google Scholar] [CrossRef]
- Kilkis, B. Net-zero buildings, what are they and what they should be? Energy 2022, 256, 124442. [Google Scholar] [CrossRef]
- Architecture 2030. New Buildings Institute, Rocky Mountain Institute. Zero Net Carbon (ZNC): A Definition. Available online: https://www.architecture2030.org/wp-content/uploads/2018/10/ZNC_Building_Definition.pdf (accessed on 11 July 2016).
- ASHRAE. Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings 2013. American Society of Heating, Refrigeration, and Air-Conditioning Engineers. Available online: https://www.ashrae.org/technical-resources/standards-and-guidelines/read-only-versions-of-ashrae-standards (accessed on 11 July 2016).
- Athienitis, A.K.; O’Brien, W. Modeling, Design, and Optimization of Net-Zero Energy Buildings; Wilhelm Ernst and Sohn, Wiley: Berlin, Germany, 2015; Available online: https://www.ernst-und-sohn.de/en/modeling-design-and-optimization-of-net-zero-energy-buildings (accessed on 11 July 2016).
- Cold Climate Air Source Heat Pump. Northeast Energy Efficiency Partnerships. 2018. Available online: https://neep.org/initiatives/high-efficiency-products/emerging-technologies/ashp/cold-climate-air-source-heat-pump (accessed on 1 January 2018).
- National Renewable Energy Laboratory. 2014 Building America House Simulation Protocols. U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, National Renewable Energy Laboratory, 2014. Available online: https://www.nrel.gov/docs/fy14osti/60988.pdf (accessed on 11 February 2016).
- National Renewable Energy Laboratory. BEopt 2016. Available online: https://beopt.nrel.gov/home (accessed on 11 February 2016).
- O’Brien, W.; Kesik, T.; Athienitis, A. Solar Design Days: A Tool for Passive Solar House Design. ASHRAE Trans. 2014, 120, 101. Available online: https://carleton.ca/hbilab/wp-content/uploads/Solar-Design-Days.pdf (accessed on 11 February 2016).
- O’Brien, W.; Athienitis, A.; Kesik, T. Parametric Analysis to support the integrated design and performance modeling of net-zero energy houses. ASHRAE Trans. 2011, 117, 1–12. Available online: https://academic.daniels.utoronto.ca/pbs/wp-content/uploads/sites/13/2023/04/Parametric-analysis-to-support-the-integrated-design-and-performance-modeling-of-net-zero-energy-houses.pdf (accessed on 11 February 2016).
- Bucking, S.; Zmeureanu, R.; Athienitis, A. A methodology for identifying the influence of design variations on building energy performance. J. Build. Perform. Simul. 2013, 7, 411–426. [Google Scholar] [CrossRef]
- Bucking, S.; Athienitis, A.; Zmeureanu, Z. Multi-Objective Optimal Design of a Near Net Zero Energy Solar House. ASHRAE Trans. 2014, 120, 224–235. Available online: https://www.researchgate.net/publication/285964004_Multi-objective_optimal_design_of_a_near_net_zero_energy_solar_house (accessed on 11 February 2016).
- Safa, A.A.; Fung, A.S.; Kumar, R. Comparative thermal performances of a ground source heat pump and a variable capacity air source heat pump system for sustainable houses. Appl. Therm. Eng. 2015, 81, 279–287. [Google Scholar] [CrossRef]
- Melo, F.C.; da Graça, G.C.; Panão, M.J.N.O. A review of annual, monthly, and hourly electricity use in buildings. Energy Build. 2023, 293, 113201. [Google Scholar] [CrossRef]
- National Building Code of Canada, Volume I. Canadian Commission on Building and Fire Codes. National Research Council, 2015. Available online: https://nrc.canada.ca/en/certifications-evaluations-standards/codes-canada/codes-canada-publications/national-building-code-canada-2015 (accessed on 11 July 2019).
- National Building Code of Canada, Volume II, Part 9. Canadian Commission on Building and Fire Codes. National Research Council, 2015. Available online: https://nrc.canada.ca/en/certifications-evaluations-standards/codes-canada/codes-canada-publications/national-building-code-canada-2015 (accessed on 11 July 2019).
- Wilbur, B. Thermal System-Specific and Net-Zero Carbon Least-Cost Design of New Houses in Canadian Cold Climates. Master’s Thesis, Ryerson University, Toronto, ON, Canada, 2018. Available online: https://rshare.library.torontomu.ca/articles/thesis/Thermal_system-specific_and_net-zero_carbon_least-cost_design_of_new_houses_in_Canadian_cold_climates/14657844 (accessed on 29 April 2024).
- National Research Council, Twin Houses. Canadian Centre for Housing Technology. Available online: http://www.ccht-cctr.gc.ca/eng/facilities/twin_houses.html (accessed on 11 February 2016).
- Portfolio Manager Greenhouse Gas Emissions Technical Reference 2017. Energy Star. Available online: https://www.energystar.gov/buildings/tools-and-resources/portfolio-manager-technical-reference-greenhouse-gas-emissions (accessed on 29 April 2024).
- Gordian. City Cost Indexes-How to Use the City Cost Indexes. Available online: www.rsmeans.com/media/wysiwyg/product_pdf/2024-BCCD-TOCs.pdf (accessed on 11 February 2016).
- Gordian. MasterFormat City Cost Index-Year 2017 Base. Available online: https://www.rsmeans.com/products/online (accessed on 10 September 2024).
- Hydro Quebec. Comparison of Electricity Prices in Major North American Cities 2017. Hydro Quebec. Available online: www.hydroquebec.com/data/documents-donnees/pdf/comparison-electricity-prices-2017.pdf (accessed on 22 November 2017).
- Ontario Energy Board. Historical Natural Gas Rates. Available online: https://www.oeb.ca/rates-and-your-bill/natural-gas-rates/historical-natural-gas-rates (accessed on 22 November 2017).
- Available online: https://remdb.nrel.gov/ (accessed on 29 April 2024).
- Canada. How Much You Need for a Downpayment. Government of Canada. Available online: https://www.canada.ca/en/financial-consumer-agency/services/mortgages/down-payment.html (accessed on 22 November 2017).
- EERE. Methodology for Evaluating Cost-Effectiveness of Residential Energy Code Changes. Office of Energy Efficiency and Renewable Energy, Building Technologies Program. U.S. Department of Energy. Available online: www.energycodes.gov/sites/default/files/2021-07/residential_methodology_2015.pdf (accessed on 22 November 2017).
- PHIUS. PHIUS+ Project Certification. 2015. Retrieved April 2016. Available online: https://www.phius.org/certifications (accessed on 10 September 2024).
Model Name | DHW | Cooling | Heating | Backup Heating | Delivery |
---|---|---|---|---|---|
Reference | Natural gas, 40 gal; Energy Factor 0.59 | Central AC; SEER 15 | Natural gas furnace; 80% AFUE | NA | Ducted air |
Gas | Natural gas (tank/tankless options) | Central AC (multiple options) | Natural gas furnace (multiple options) | NA | Ducted air |
ASHP | HPWH 80-gal; Energy Factor 2.3 | Central ASHP; SEER 22 | Central ASHP; 10 HSPF | Integrated electric | Ducted air |
MSHP | HPWH 80-gal; Energy Factor 2.3 | Ductless MSHP; SEER 22 | Ductless MSHP; 11 HSPF | Baseboard electric | 4 Indoor units |
GSHP | HPWH 80-gal; Energy Factor 2.3 | Central GSHP; EER 20.2 | Central GSHP; COP 4.2 | Integrated electric | Ducted air |
Electric | Electric tank, 50 gal; Energy Factor 0.95 | Window AC; EER 10.7 | Electric baseboard | NA | NA |
Location (NBC 2015) | Elevation (m) | Latitude (N) | Design Temperature | Degree Days below 18 °C | NBC Zone | EF g CO2e/kWh | ||||
---|---|---|---|---|---|---|---|---|---|---|
January | July 2.5% | |||||||||
2.5% °C | 1% °C | Dry °C | Wet °C | Ave | Mar | |||||
Vancouver | 120 | 49°15′ | −6 | −8 | 28 | 20 | 2925 | 4 | 10.1 | 517 |
Edmonton | 645 | 53°32′ | −30 | −33 | 28 | 19 | 5120 | 7A | 960 | 469 |
Toronto | 175 | 43°42′ | −20 | −22 | 31 | 24 | 3760 | 5 | 40 | 394.3 |
Montreal | 45 | 45°30′ | −23 | −26 | 30 | 23 | 4270 | 6 | 1.9 | 330.9 |
Halifax | 55 | 44°38′ | −16 | −18 | 26 | 20 | 4000 | 6 | 710 | 712 |
City | Material | Labour/Inst. |
---|---|---|
Vancouver | 115.6 | 93.9 |
Edmonton | 119.8 | 98.6 |
Toronto | 114.5 | 105.6 |
Montreal | 115.7 | 91.5 |
Halifax | 116.1 | 85 |
Location | Electricity | Natural Gas | ||
---|---|---|---|---|
Marginal (CAD/kWh) | Fixed (CAD/Month) | Marginal (CAD/GJ) | Fixed (CAD/Month) | |
Vancouver | $0.1101 | $8.26 | $7.19 | $12.75 |
Edmonton | $0.0785 | $30.10 | $6.55 | $49.50 |
Toronto | $0.1048 | $34.89 | $7.95 | $22.60 |
Montreal | $0.0670 | $14.25 | $14.76 | $18.98 |
Halifax | $0.1582 | $11.37 | $20.97 | $25.15 |
Design Name | Space Conditioning System | Price Metrics (CAD) | ||||||
---|---|---|---|---|---|---|---|---|
Heating Main | Supplementary Electric | Cooling (AC) | Delivery (Ducting) | |||||
Capacity [Output] ($/kBtuh) | Fixed ($/Unit) | Capacity ($/kBtuh) | Capacity ($/kBtuh) | Fixed ($/Unit) | Area ($/ft2) | Total ($/Unit) | ||
Reference | Gas 80% AFUE + AC SEER 15 | $3.09 | $2157 | $48.09 | $2698.83 | $5.56 | $5266.99 | |
Gas | Gas 92.5% AFUE + AC SEER 16 | $4.78 | $2630.60 | $48.09 | $2840.81 | $7.04 | $6669.00 | |
ASHP | ASHP 10 HSPF; SEER 22 | $48.09 | $4395.00 | $7.04 | $6669.00 | |||
MSHP | MSHP 11 HSPF + baseboard | $92.75 | $1856.62 | $41.78 | ||||
GSHP | GSHP 4.2 COP; EER 20.2 | $564.25 | $1833.36 | $7.04 | $6669.00 | |||
Electric | Baseboard electric + window AC | $41.78 | $50.95 | $38.02 |
Economics | Mortgage | ||
---|---|---|---|
Project Analysis Period (yr.) | 30 | Down Payment | 20% |
Inflation Rate | 1.54% | Mortgage Interest Rate | 3.90% |
Discount Rate (Real) | 2.33% | Mortgage Period (yr.) | 30 |
Discount Rate (Nominal) | 3.90% |
Group | Category | 1 | 2 | 3 | 4 |
---|---|---|---|---|---|
Space Conditioning | Central Air Conditioner | SEER 15 | SEER 16 (2 stage) | SEER 18 | SEER 24.5 |
Gas Furnace | 80% AFUE | 92.5% AFUE | 95% AFUE | 98% AFUE | |
Water Heating | Gas Water Heater | Energy Factor: 0.59 | Condensing; Energy Factor: 0.82 | Tankless; Energy Factor: 0.82 | Tankless condensing; Energy Factor: 0.96 |
Group | Category | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
---|---|---|---|---|---|---|---|---|---|---|---|
Walls | 1 | Wall sheathing | None | R-5 XPS | R-10 XPS | R-15 XPS | R-20 XPS | R-25 XPS | R-30 XPS | R-35 XPS | R-40 XPS |
Ceilings/Roofs | 2 | Unfinished attic | R-38 (39.6) | R-49 (50.6) | R-60 (61.6) | R-70 (71.6) | |||||
3 | Radiant barrier | None | Double-sided foil | ||||||||
Foundation/Floors | 4 | Unfinished basement | R-12 polyiso (13.3) | R-18 polyiso (19.3) | (22.6) | (28.1) | (33.4) | (38.6) | |||
Windows and Doors | 5 | Window areas | back: 23% | Back: 33% | Back: 43% | ||||||
6 | Windows | U-value 0.32 | U-value 0.3 | U-value 0.29 | U-value 0.27 | U-value 0.3 (triple) | U-value 0.29 (triple) | U-value 0.21 (triple) | U-value 0.18 (triple) | ||
7 | Overhangs | None | Back windows: 2′ | Back windows: 3′ | |||||||
Airflow | 8 | Air leakage | 2.5 ACH50 | 2 ACH50 | 1 ACH50 | 0.6 ACH50 | |||||
9 | Mechanical ventilation | HRV, SRE: 70% | ERV, SRE: 70%, TRE: 0.48% | ||||||||
Space Conditioning | 10 | Duct insulation | None | R-4 | R-8 | ||||||
11 | Ceiling Fans (four fans) | 45 W/fan | 20 W/fan | ||||||||
Hot Water | 12 | Pipe insulation | None | R-2 | R-5 | ||||||
13 | Shower DWHR | None | 53% efficiency |
Group | Category | Ref-TO | Gas-VN | Gas-ED | Gas-TO | Gas-ML | Gas-HX |
---|---|---|---|---|---|---|---|
Walls | Wall sheathing | None | None | None | None | R-15 XPS | R-20 XPS |
Ceilings/Roofs | Unfinished attic | R-38 (39.6) | R-38 (39.6) | R-49 (50.6) | R-38 (39.6) | R-60 (61.6) | R-60 (61.6) |
Radiant barrier | None | None | None | None | None | None | |
Foundation/Floors | Unfinished basement | R-18 polyiso (19.3) | R-12 polyiso (13.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) |
Windows and Doors | Window areas | Back: 23% | Back: 23% | Back: 23% | Back: 23% | Back: 23% | Back: 23% |
Windows | U-value 0.32 | U-value 0.32 | U-value 0.27 | U-value 0.32 | U-value 0.27 | U-value 0.27 | |
Overhangs | None | None | None | None | None | None | |
Airflow | Air leakage | 2.5 ACH50 | 2.5 ACH50 | 0.6 ACH50 | 1 ACH50 | 0.6 ACH50 | 0.6 ACH50 |
Mechanical ventilation | HRV, SRE: 70% | HRV, SRE: 70% | HRV, SRE: 70% | ERV, SRE: 70%, TRE: 0.48% | ERV, SRE: 70%, TRE: 0.48% | HRV, SRE: 70% | |
Space Conditioning | Duct insulation | None | R-8 | R-8 | R-8 | R-8 | R-8 |
Ceiling fans (four fans) | 45 W/fan | 45 W/fan | 45 W/fan | 45 W/fan | 45 W/fan | 45 W/fan | |
Hot Water | Pipe insulation | None | R-2 | R-2 | R-5 | R-5 | R-5 |
Shower DWHR | None | None | None | None | DWHR | DWHR | |
Gas model-specific options | |||||||
Space Conditioning | Central air conditioner | SEER 15 | SEER 15 | SEER 16 (2 stage) | SEER 16 (2 stage) | SEER 16 (2 stage) | SEER 15 |
Furnace | 80% AFUE | 92.5% AFUE | 92.5% AFUE | 92.5% AFUE | 92.5% AFUE | 92.5% AFUE | |
Water Heating | Water heater | Energy factor: 0.59 | Tankless; energy factor: 0.82 | Tankless; energy factor: 0.82 | Tankless; energy factor: 0.82 | Tankless; energy factor: 0.82 | Tankless condensing; energy factor: 0.96 |
Group | Category | Ref-TO | Gas-TO | ASHP-TO | MSHP-TO | GSHP-TO | Electric-TO |
---|---|---|---|---|---|---|---|
Walls | Wall sheathing | None | None | None | R-20 XPS | None | R-20 XPS |
Ceilings/Roofs | Unfinished attic | R-38 (39.6) | R-38 (39.6) | R-60 (61.6) | R-60 (61.6) | R-38 (39.6) | R-60 (61.6) |
Radiant barrier | None | None | None | None | None | None | |
Foundation/Floors | Unfinished basement | R-18 polyiso (19.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) | R-18 polyiso (19.3) |
Windows and Doors | Window areas | Back: 23% | Back: 23% | Back: 23% | Back: 23% | Back: 23% | Back: 23% |
Windows | U-value 0.32 | U-value 0.32 | U-value 0.32 | U-value 0.32 | U-value 0.32 | U-value 0.29 | |
Overhangs | None | None | None | None | None | None | |
Airflow | Air leakage | 2.5 ACH50 | 1 ACH50 | 0.6 ACH50 | 0.6 ACH50 | 2 ACH50 | 0.6 ACH50 |
Mechanical ventilation | HRV, SRE: 70% | ERV, SRE: 70%, TRE: 48% | HRV, SRE: 70% | HRV, SRE: 70% | HRV, SRE: 70% | HRV, SRE: 70% | |
Space Conditioning | Duct insulation | None | R-8 | R-8 | NA | R-8 | NA |
Ceiling fans (four fans) | 45 W/fan | 45 W/fan | 45 W/fan | 45 W/fan | 45 W/fan | 45 W/fan | |
Hot Water | Pipe insulation | None | R-5 | R-5 | R-5 | R-5 | R-5 |
Shower DWHR | None | None | DWHR | DWHR | DWHR | DWHR |
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Wilbur, B.; Fung, A.S.; Kumar, R. Thermal System and Net-Zero-Carbon Least-Cost Design Optimization of New Detached Houses in Canada. Buildings 2024, 14, 2870. https://doi.org/10.3390/buildings14092870
Wilbur B, Fung AS, Kumar R. Thermal System and Net-Zero-Carbon Least-Cost Design Optimization of New Detached Houses in Canada. Buildings. 2024; 14(9):2870. https://doi.org/10.3390/buildings14092870
Chicago/Turabian StyleWilbur, Brandon, Alan S. Fung, and Rakesh Kumar. 2024. "Thermal System and Net-Zero-Carbon Least-Cost Design Optimization of New Detached Houses in Canada" Buildings 14, no. 9: 2870. https://doi.org/10.3390/buildings14092870