Figure 1.
LCC vs. GHG optimization analysis representation.
Figure 1.
LCC vs. GHG optimization analysis representation.
Figure 2.
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.
Figure 2.
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.
Figure 3.
Model geometry-clockwise from top left: north, south, west, east (green = conditioned volume).
Figure 3.
Model geometry-clockwise from top left: north, south, west, east (green = conditioned volume).
Figure 4.
Reference model SHDI and EUI values.
Figure 4.
Reference model SHDI and EUI values.
Figure 5.
Reference model EUI Breakdown by end-use for thermal-system-specific Toronto baseline models (hatching = natural gas, solid = electricity).
Figure 5.
Reference model EUI Breakdown by end-use for thermal-system-specific Toronto baseline models (hatching = natural gas, solid = electricity).
Figure 6.
Toronto MSHP design cash flows (chart excludes residual value: $79,938 in year 30, i.e., a negative cost).
Figure 6.
Toronto MSHP design cash flows (chart excludes residual value: $79,938 in year 30, i.e., a negative cost).
Figure 7.
Gas-TO optimization plot with exterior wall insulation sensitivity frontiers.
Figure 7.
Gas-TO optimization plot with exterior wall insulation sensitivity frontiers.
Figure 8.
The optimal design arranged from left to right and top to bottom, starting with Vancouver, followed by Edmonton, Toronto, Montreal, and finally, Halifax.
Figure 8.
The optimal design arranged from left to right and top to bottom, starting with Vancouver, followed by Edmonton, Toronto, Montreal, and finally, Halifax.
Figure 9.
Edmonton NZE optimization results with PV systems.
Figure 9.
Edmonton NZE optimization results with PV systems.
Figure 10.
Initial cost optimal designs—Toronto (“fixed” includes lighting, appliances, ceiling fans, doors, eaves, and thermal mass).
Figure 10.
Initial cost optimal designs—Toronto (“fixed” includes lighting, appliances, ceiling fans, doors, eaves, and thermal mass).
Figure 11.
Annual energy use by end-use—Toronto (hatched = natural gas, solid = electricity).
Figure 11.
Annual energy use by end-use—Toronto (hatched = natural gas, solid = electricity).
Figure 12.
Annual energy costs of optimal models—Toronto (E = electricity, G = natural gas).
Figure 12.
Annual energy costs of optimal models—Toronto (E = electricity, G = natural gas).
Figure 13.
Annual GHG emissions by fuel type—Toronto.
Figure 13.
Annual GHG emissions by fuel type—Toronto.
Figure 14.
The SHDI of optimal Toronto design enclosures; the orange line represents the climate-specific North American Passive House Standard Target [
32].
Figure 14.
The SHDI of optimal Toronto design enclosures; the orange line represents the climate-specific North American Passive House Standard Target [
32].
Figure 15.
Hourly heating delivered by the MSHP—Toronto.
Figure 15.
Hourly heating delivered by the MSHP—Toronto.
Figure 16.
Annual hourly electric load profile of heat pump and whole building for MSHP—Toronto design.
Figure 16.
Annual hourly electric load profile of heat pump and whole building for MSHP—Toronto design.
Figure 17.
January day electric load profile—Toronto.
Figure 17.
January day electric load profile—Toronto.
Figure 18.
Energy use versus GHG emissions—Toronto (orange = MSHP design variants, blue = gas design variants).
Figure 18.
Energy use versus GHG emissions—Toronto (orange = MSHP design variants, blue = gas design variants).
Figure 19.
Energy use versus GHG emissions—Edmonton.
Figure 19.
Energy use versus GHG emissions—Edmonton.
Table 1.
Thermal system model inputs summary. “NA” means “Not Applicable”.
Table 1.
Thermal system model inputs summary. “NA” means “Not Applicable”.
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 |
Table 2.
Climate, location data, electric grid annual average, and marginal EFs.
Table 2.
Climate, location data, electric grid annual average, and marginal EFs.
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 |
Table 3.
RSMeans (2017) CCI [
25,
26].
Table 3.
RSMeans (2017) CCI [
25,
26].
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 |
Table 4.
Electricity and natural gas prices used in the modelling [
27,
28].
Table 4.
Electricity and natural gas prices used in the modelling [
27,
28].
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 | $25.15 |
Table 5.
Space conditioning system input capital costs.
Table 5.
Space conditioning system input capital costs.
Design Name | Space Conditioning System | Price Metrics (CAD) |
---|
Heating Main | Supplementary Electric | Cooling (AC) | Delivery (Ducting) |
---|
Capacity [Output] ($/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 | | |
Table 6.
Mortgage and financial project inputs.
Table 6.
Mortgage and financial project inputs.
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% | | |
Table 7.
Optimization design input options—gas model only.
Table 7.
Optimization design input options—gas model only.
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 |
Table 8.
Optimization design input options for all models.
Table 8.
Optimization design input options for all models.
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 | | | | | | | |
Table 9.
Resultant lowest LCC gas designs by location. In this Table, VN stands for Vancouver, ED for Edmonton, TO for Toronto, ML for Montreal, and HX for Halifax.
Table 9.
Resultant lowest LCC gas designs by location. In this Table, VN stands for Vancouver, ED for Edmonton, TO for Toronto, ML for Montreal, and HX for Halifax.
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 |
Table 10.
Resultant lowest-LCC designs for all thermal system types—Toronto (TO).
Table 10.
Resultant lowest-LCC designs for all thermal system types—Toronto (TO).
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 |