Implications of the BC Energy Step Code on GHG Emissions

 
Implications of the BC Energy Step Code on GHG Emissions
DRAFT ONLY – DO NOT CIRCULATE

    Implications of the
    BC Energy Step Code
    on GHG Emissions
    June 2019

    Prepared for the Building and Safety
    Standards Branch, Ministry of Municipal
    Affairs and Housing

    By:
    Integral Group
    Suite 180 - 200 Granville Street
    Vancouver, BC V6C 1S4
Implications of the BC Energy Step Code on GHG Emissions
Contents
EXECUTIVE SUMMARY....................................................................................................................................... 3
1          INTRODUCTION .................................................................................................................................... 8
2          PURPOSE OF THE STUDY ...................................................................................................................... 9
3          METHOD .............................................................................................................................................. 10
           The BC Energy Step Code Metrics Research Report ....................................................................................10
           Part 9 Buildings – Methodology ......................................................................................................................11
           Part 3 Buildings – Methodology ......................................................................................................................13
4          ANALYSIS............................................................................................................................................. 14
           Understanding Building Emissions Performance ........................................................................................14
           Building Emissions – Part 9 .............................................................................................................................16
           Building Emissions – Part 3 .............................................................................................................................21
           Incremental Construction Costs – Part 9 .......................................................................................................23
           Incremental Construction Costs – Part 3 .......................................................................................................27
           Absolute Emissions ..........................................................................................................................................30
           Using Renewable Natural Gas ........................................................................................................................33
           Life Cycle Emissions .........................................................................................................................................35
5          POLICY DISCUSSION & CONCLUSIONS ............................................................................................. 36
           Adopting GHGI Targets ....................................................................................................................................36
           Energy Efficiency Standards ............................................................................................................................38
           Other Building-Scale Regulatory Options......................................................................................................38
           Province-Wide Energy Regulation ..................................................................................................................39
           Removing Barriers to Low-Emissions Buildings ...........................................................................................39
6          LIMITATIONS AND AREAS FOR FUTURE ANALYSIS .......................................................................... 40
           Limitations .........................................................................................................................................................40
           Areas for Future Analysis ................................................................................................................................40
APPENDIX A PART 9 ARCHETYPE SUMMARIES .............................................................................................. 42
APPENDIX B ENERGY PRICES .......................................................................................................................... 46
APPENDIX C PART 3 ARCHETYPE SUMMARIES .............................................................................................. 48
APPENDIX D PART 3 METHODOLOGY SUMMARY ......................................................................................... 54
APPENDIX E PART 9 BUILDINGS –DETAILED GHGI VS STEP CODE TABLE .................................................... 56
APPENDIX F PART 3 BUILDINGS – DETAILED GHGI VS STEP CODE TABLE ................................................... 61

                                                                                       1
Implications of the BC Energy Step Code on GHG Emissions
APPENDIX G PART 9 ABSOLUTE EMISSIONS.................................................................................................. 64
APPENDIX H PART 3 ABSOLUTE EMISSIONS ................................................................................................. 67
APPENDIX I RENEWABLE NATURAL GAS ANALYSIS...................................................................................... 69
I.1 PART 9 RNG ANALYSIS ............................................................................................................................... 69
I.2 PART 3 RNG ANALYSIS ............................................................................................................................... 72
I.3 PART 9 – DETAILED RNG ANALYSIS – COSTING IMPACTS ........................................................................ 74
I.4 PART 3 – DETAILED RNG ANALYSIS – COSTING IMPACTS ........................................................................ 76
APPENDIX J LOWER MAINLAND JURISDICTIONS OFFERING RELAXATIONS FOR CONNECTING TO LCES 77

                                                                            2
Implications of the BC Energy Step Code on GHG Emissions
EXECUTIVE SUMMARY

Background

The BC Energy Step Code (“Step Code”) represents an important step in improving the energy efficiency of
the buildings sector in British Columbia (BC). It established a consistent and predictable approach to the
regulation of energy efficiency across the province, and is the primary framework that local governments
must reference when they wish to encourage or require higher levels of energy efficiency than the base
building code.

The Step Code was also established as a means of reducing greenhouse gas (GHG) emissions from the
buildings sector. With the release of CleanBC in December 2018, the Province has signalled its intention to
adopt higher tiers of the Step Code as a means of achieving its emissions reduction goals. This will be
implemented alongside a commitment to increasing the percentage of natural gas supplied by renewable
natural gas (RNG), to a minimum of 15% of the province’s total gas supply by 2030. Commendably, CleanBC
envisions a future in which buildings contribute no GHG emissions at all.

While the Step Code represents a significant achievement in the regulation of building performance, its
focus on the use of energy efficiency metrics has raised the question as to whether it is in fact effective in
reducing greenhouse gas emissions from the built environment. This report presents the results of a study
intended to answer this question, and to initiate an exploration into possible means of increasing the rate
and magnitude of emissions reductions necessary to meet the Province’s CleanBC goal of reducing GHG
emissions in the building sector 40% by 2030.

Study Method

The analysis performed in this report is based on the Metrics Report, a comprehensive study of the
economic implications of the Step Code commissioned by BC Housing in 2017 and updated in 2018. The
Metrics Report generated a massive dataset of modelled Part 9 buildings, which was distilled into a usable
set of files for Climate Zone 4 that included the 25 lowest incremental construction cost (ICC) results and the
10 lowest greenhouse gas intensity (GHGI) results for each step. These results were then filtered to
construct comparison matrices for each Part 9 building archetype to show the GHGIs of the Step Code for a
range of different mechanical system configurations.

For Part 3 buildings, modelled results for Part 3 were somewhat more restricted and did not include all
configurations needed for this study. As such, a summary file was built by drawing results from the
modelled Part 3 end use files. Where a configuration did not exist, simple calculations were applied to
convert a modelled result to represent the desired configuration. These results were then used to construct
comparison matrices for each Part 3 building archetype to show the GHG intensities of the Step Code for a
range of mechanical system configurations. Configurations for both Part 3 and Part 9 buildings included:

   •   All Gas                                                 •   All Electric (heat pump)
   •   All Electric (resistance)                               •   Hybrid (combination of gas/electric)

                                                       3
Implications of the BC Energy Step Code on GHG Emissions
Key Findings

Overall, the results of the study show that that while the Step Code is an effective tool for driving significant
emissions reductions in select building types and configurations, it can nevertheless result in buildings that
continue to emit significant emissions over their lifetime. In short, the Step Code’s focus on energy efficiency
does not guarantee the level of emissions reductions necessary to drive emissions to zero or near-zero
levels. Building designers can pursue mechanical system options that result in significantly higher GHGIs,
potentially hampering the Province’s ability to realize CleanBC’s future vision of zero emissions buildings.

                •              While the energy efficiency of buildings is greatly improved, the implementation of the Step Code
                               can nevertheless result in significant variations in the total GHGI of different building, even at higher
                               steps. Depending on mechanical heating systems selected, GHGI varied by:
                                   o An average of 91% for Part 9 buildings, and
                                   o An average of 92% for Part 3 buildings.

                •              Even at the highest Steps, the Step Code does not require designers to select a low-carbon
                               mechanical system – in other words, the energy efficiency targets set by the Step Code can be met
                               using a range of mechanical systems.

                •              The Step Code drives emissions intensity reductions in gas-based systems, but electric-based
                               systems offer very low GHGIs (around or below 1 kgCO2e/m2.y) independent of the Step achieved.

To provide more detail on the findings above, GHGIs for Part 9 and Part 3 buildings by mechanical heating
system are shown in the figures below (averaged across all archetypes). The City of Vancouver’s (CoV) GHGI
targets are shown alongside each step to provide a context for a low-emissions building.

                           12
Average GHGI (kgCO2e/m2.y) -

                           10                                                         CoV Detached
                                                                                    Housing GHGI Limit
    All Part 9 Archetypes

                               8                                                       (2020 Bylaw)

                               6

                               4

                               2

                               0
                                      Step 1            Step 2           Step 3         Step 4          Step 5
                                        Electric Heat Pump        Electric Resistance     Gas        Hybrid

Part 9 - GHG Intensity by Mechanical System (average across all archetypes)

                                                                                4
Implications of the BC Energy Step Code on GHG Emissions
14
                                             COV Commercial
Average GHGI (kgCO2e/m2.y) -

                               12              GHGI (2016           COV Low Rise
                                               Rezoning)             MURB GHGI             COV High Rise
    All Part 3 Archetypes

                               10                                  (2016 Rezoning)          MURB GHGI
                                                                                          (2016 Rezoning)
                                8

                                6

                                4

                                2

                                0
                                    Step 1               Step 2                 Step 3            Step 4

                                    Electric Heat Pump    Electric Resistance     Gas    Hybrid

Part 3 - GHG Intensity by Mechanical System (average across all archetypes)

The Costs of Emissions Reductions

The results of this study also found that Part 9 incremental construction costs (ICCs) increase with increasing
Steps, with a significant increase from Step 4 to Step 5 seen for most archetypes and heating system types.
For all archetypes, hybrid and electric resistance-based heating systems provided the lowest ICCs at lower
Steps. Electric heat pumps show a significant premium over other heating systems at lower Steps, but by
Step 5 are typically in the same range (or lower) than other heating system options. ICCs for gas-based
heating systems varied depending on building archetype, indicating that archetype is an important factor in
determining the affordability of gas-based heating systems.

Part 9 energy costs are lowest for electric heat pump and gas-based scenarios. Low capital cost electric
resistance heating systems have the highest operating energy costs, due to the high cost of electricity
compared to natural gas. Hybrid systems, either combined heat pump/electric resistance or gas/electric,
may provide a reasonable balance of construction and operating costs. Life cycle costing information
(incremental construction and operating costs) was not available for electric heating system scenarios for
Part 3 buildings. However, high-level trends are expected to be similar to those seen for Part 9 buildings.

                                                                      5
Implications of the BC Energy Step Code on GHG Emissions
The Impact of Renewable Natural Gas

CleanBC’s commitment to a minimum of 15% RNG in the province’s total gas supply by 2030 will further
drive down emissions for buildings with gas-based heating systems. The 2030 15% target is expected to
reduce GHGIs by 11% to 14% in buildings with all gas or hybrid electric heating systems. RNG comes with an
energy cost premium, but the impact to total building energy costs is expected to be minimal, on average
only increasing annual energy costs 1.5%.

While RNG offers benefits to buildings operating with gas-based systems, it is not expected to completely
replace conventional natural gas. As such, while buildings with gas-based systems will see GHGI reductions
as RNG supply increases, the overall GHGI will remain linked to carbon-intensive natural gas and remain
significantly higher than electric-based system.

Exploring Policy Options

Despite the ability of the Step Code to reduce emissions in some building archetypes, the results above
show that additional policy should be considered as a way to drive down emissions in new buildings and
support British Columbia’s climate and emissions goals. The study considered five broad policy tools to
further encourage GHG emissions reductions in new construction as a preliminary exploration into possible
methods of achieving emissions reductions:

   1. Setting GHGI Targets: Adopting a set of GHGI targets alongside energy efficiency metrics into the
      Step Code (or elsewhere in the Building Act) would provide local governments with the necessary
      tools to ensure emissions reductions are achieved when implementing the BC Building Code.
      Targets could be developed either as optional or as a part of required metrics to achieve. GHGI
      targets have been set in other jurisdictions as a means of encouraging emissions reductions,
      including the City of Vancouver’s Zero Emissions Buildings Plan.

   2. Energy Efficiency Standards: British Columbia’s efficiency standards will begin to increase in 2020
      through to 2035, including for building space and water heating equipment. Combined with a
      stepped GHGI target, this regulation could drive the adoption of high-efficiency heat pumps over
      lower-efficiency electric options (such as baseboard heaters) where the required coefficient of
      performance (COP) is above 1. Some jurisdictions (e.g. Burnaby, Vancouver) already require high
      efficiency systems for their approved low-carbon energy systems in requiring seasonal average COP
      greater than 2.

   3. Other Building-Scale Regulations: Since heat pumps can achieve low GHGIs while providing both
      space heating and cooling, mandating mechanical cooling within the BC Building Code could also
      lead to reductions in building operational GHG emissions. Such a regulation (via an amendment to
      the BC Building Code) is already being considered by Provincial authorities as a means of
      safeguarding the health and safety of building occupants under a warming climate. Such a
      requirement would create a significant market for heat pump adoption and result in a significant
      shift towards building electrification, even in the absence of more targeted regulation. Similarly,
      regulating the use of gas-based cooking appliances as a way to address growing concerns over

                                                     6
Implications of the BC Energy Step Code on GHG Emissions
indoor air quality could help support lower-carbon mechanical options, albeit to a lesser extent
       given their low contribution to total operational emissions.

   4. Province-Wide Energy Regulations: Two supply-side measures that have already been introduced
      represent additional means to reduce building emissions: the current carbon tax, and the proposed
      increase in the supply of RNG into the natural gas supply. While the intention of both these
      mechanisms is to reduce province-wide emissions, they represent only partial solutions. Even with
      the carbon tax’s projected increase to $50/tonne, natural gas will still offer a significant cost savings
      versus electricity and taken alone is not likely to be a sufficient driver towards low-carbon energy
      sources. As noted above, a 15% RNG supply only offsets a maximum of 14% of annual building
      operational emissions, and risks perpetuating the use of GHG-intensive gas-based systems that will
      increase emissions over the longer term.

   5. Removing Barriers to Low-Emissions Buildings: While insufficient on their own to adequately
      reduce building emissions, provincial and local governments can both offer financial and other
      incentives as a means of encouraging the adoption of low-carbon systems. One form of non-
      financial incentive is to encourage the use of low-carbon energy systems in return for lower
      thresholds for energy performance. Local governments can also explore the use of building
      approvals, planning and development processes as a means of encouraging LCES, such as density
      bonusing, parking relaxations, property tax abatements, and expedited permitting. Financial
      incentives can also be offered as a way to reduce the up-front costs of installing low-carbon energy
      systems.

It should be noted that this review constituted only a preliminary exploration of potential policy options. A
full evaluation of policy options including a clear set of evaluative criteria should be used in combination
with key stakeholder engagement to determine the next best step for Provincial and local government
authorities to take.

                                                       7
Implications of the BC Energy Step Code on GHG Emissions
1    INTRODUCTION

The Province of British Columbia (BC) introduced the BC Energy Step Code (“Step Code”) in 2017 via an
amendment to the BC Building Code (BCBC) that allowed for a performance-based pathway to support
increasing levels of energy efficiency in new construction. The Step Code sets out a series of increasingly
stringent requirements for energy use, thermal energy demand, and airtightness to eventually require all
new buildings in BC to be constructed to a net-zero energy-ready level of performance by 2032.
Performance thresholds have been developed for:

    •    Part 9 residential buildings in Climate Zones 4, 5, and 6/7a/7b/8, and
    •    Part 3 multi-unit residential (Group C) and large commercial buildings (Group D & E) in Climate Zone
         4 (now applicable across all climate zones). 1

One of the central reasons for development of the Step Code was to establish consistency and predictability
in the way that local governments regulate energy efficiency across the province. As of December 2017, local
governments regulated by the BC Building Act and Community Charter are required to reference the Step
Code where they wish to encourage or require higher levels of energy efficiency than the base building
code. Local governments are permitted to require higher levels of the Step Code in advance of their official
adoption at the provincial level.

A second key rationale behind the development of the Step Code is to achieve greenhouse gas (GHG)
emissions reductions in the building sector. In December of 2018, the provincial government released
CleanBC, the Province’s plan to reduce GHG emissions from buildings, transportation, and industry. It sets a
target of reducing GHG emissions in the building sector by 40% by 2030. For new construction, there are
currently two primary means through which the Province has indicated it will meet its emissions reduction
targets. First, an increasing percentage of natural gas is to be supplied by renewable natural gas (RNG), with
a minimum requirement of 15% of the province’s total gas supply set for 2030. The second major tool is
through the adoption of higher tiers of the Step Code, with the expectation that higher levels of energy
efficiency will translate into emissions reductions. CleanBC affirms the Province’s intent to update the
Building Code to mandate increasingly higher steps of BC’s Energy Step Code in 2022 and 2027 and the
highest step in 2032. CleanBC also envisions a future in which buildings contribute no GHG emissions at all.

1
 Part 9 Buildings are defined as those three storeys and under in height and with a footprint of 600 square metres or less, while Part 3
Buildings are those over three storeys in height or over 600 square metres in footprint. Part 3 also includes some buildings of three
storeys or less in height or under 600 square metres in area that are of a specific use, such as public gatherings, residential care,
detention, or high-hazard industrial activities.

                                                                   8
2   PURPOSE OF THE STUDY

The Step Code is a significant achievement in provincial building energy and emissions regulation – one that
has been recognized across North America for its strong intent, clear pathway, and replicable approach.
However, several local governments in BC have called for a more direct means of regulating emissions from
new construction, noting that improvements in energy efficiency alone are insufficient in guaranteeing the
low-carbon outcomes needed to meet their own community-wide emissions reduction targets. Results
found in the BC Energy Step Code Metrics Research Report (“Metrics Report”) have furthermore indicated
that projects that adopt a higher step of the Step Code may still result in high operational emissions (see
Metrics Research Report 2018, p. 73). While the Metrics Report only began to unpack the implications of the
Step Code on building emissions, it nevertheless indicates the need for a deeper investigation into the
relationship between the Step Code and emissions reductions.

The purpose of this study is therefore to explore the effect of Step Code adoption on greenhouse gas
emissions in new Part 9 and Part 3 buildings. Specifically, it assesses the range of possible GHG emission
reductions in new building construction at each step of the BC Energy Step Code in Climate Zone 4,
including the potential impact of potential increases in RNG into the building energy sector. The results
contained in this report represent a first phase of work completed in early 2019, and are intended to inform
additional analyses. It outlines the methods used to derive these preliminary results, identifies potential
policy options to explore, and characterizes limitations and necessary areas of future study in the report’s
conclusion.

This study was made possible by a financial contribution from Natural Resources Canada and led by the BC
Ministry of Municipal Affairs and Housing. Additional guidance was provided by the following individuals
and institutions:
    •   Emily Sinclair and Dale Andersson, Building Safety and Standards Branch, Province of BC
    •   Urszula Mezynska, Planning and Land Use Management, Province of BC
    •   Katherine Muncaster, Energy Efficiency Branch, Province of BC
    •   Tyler Bryant and Dana Wong, FortisBC
    •   Christian Cianfrone, ZEBx
    •   Lise Townsend, City of Burnaby
    •   Laura Sampliner, City of Port Moody
    •   Maxwell Sykes, City of Surrey
    •   Chris Higgins, City of Vancouver
    •   Maggie Baynham and Ting Pan, District of Saanich
    •   Ralph Wells, University of British Columbia

                                                      9
3   METHOD

        The BC Energy Step Code Metrics Research Report

The analysis presented in this report is based on the Metrics Report, a comprehensive study of the
economic implications of the Step Code commissioned by BC Housing in 2017 and updated in 2018. The
purpose of the Metrics Report was to:

    •    Explore the implications of the Step Code for the BC building industry with respect to the potential
         design solutions that would be required to meet Step Code targets
    •    Assess the potential costs of these design solutions, and
    •    Identify any potential modifications to the Step Code that could be required to ensure its effective
         and equitable adoption.

The Metrics Report made use of parametric modelling techniques that allowed for the analysis of several
hundred thousand combinations of design strategies that could be employed to meet the range of Step
Code targets for different building archetypes and in different climate zones. The primary focus of the
report was to identify the likely incremental capital costs (ICC, or first costs), operating costs, and lifecycle
GHG abatement costs associated with meeting the Step Code as a means of identifying the feasibility of its
adoption across the province. The Metrics Report was updated in 2018 to include targets developed for Part
3 Hotels/Motels and Commercial Offices, as well as modifications to the Part 9 targets intended to improve
equity across building archetypes and climate zones.

The Metrics Report optimized steps within the Step Code for both lowest cost and for the highest Net
Present Value (NPV) to assess both capital costs and long-term cost effectiveness. As such, Metrics Report
results were not optimized to either account for or minimize GHG emissions from new construction. Report
results showed that the lowest ICC results for certain building archetypes could translate into higher GHG
emissions intensities over the baseline, even at higher Steps (i.e. Steps 3, 4 or 5). This was seen where
buildings shifted to a natural gas-based source of space heating and DHW, particularly where the baseline
BCBC building was assumed to rely on electricity. However, while the primary focus of the Metrics Report
was to identify the costs associated with the implementation of the Step Code, the large dataset of modelled
archetypes represents a wealth of data that can be used to explore other dimensions, including means of
optimizing GHG reductions.

Different approaches to modelling were used for Part 3 and Part 9, which resulted in different datasets.
Details on each one and how they were used in the analysis are presented below.

                                                       10
Part 9 Buildings – Methodology

The Metrics Report modelled six base building archetypes using Version 11.3 of Natural Resources Canada
(NRCan)’s HOT2000 program, an energy simulation and design tool used for low-rise residential buildings.
Each archetype was designed with various combinations of energy conservation measures (ECMs), which
resulted in nearly 54 million possible modelling combinations for each archetype. Base archetypes are
described below, with additional details provided in Appendix A.

 Archetype                         Details
 MURB (10 units)                   Market, 1,654m2, 1,780ft2/unit, 3 storeys over underground parkade
 Row House (6 units)               Market, 957m2, 1,720ft2/unit, 3 storeys over underground parkade
 Quadplex                          Market, 513m2, 1,382ft2/unit, 3 storeys over underground parkade
 Large Single-Family Dwelling      Market, 511m2, 5,500ft2, 2 storeys with basement
 Medium Single-Family Dwelling     Market, 237m2, 2,551ft2, 2 storeys with basement
 Small Single-Family Dwelling      Market, 102m2, 1,098ft2, single storey on heated crawlspace

The Metrics Report generated a massive dataset of modelled Part 9 buildings. This dataset was distilled into
a usable set of files for Climate Zone 4 that includes the 25 lowest incremental construction cost (ICC) results
for each step, and the 10 lowest GHGI results for each step. These results were then filtered to construct
comparison matrices for each Part 9 building archetype to show the GHG intensities of the Step Code for a
range of different mechanical system configurations. These configurations included the following:
    •    All Gas:
             o Space heating: base furnace, high efficiency furnace, OR combination space/hot water system
                 with gas based hot water heater
             o Hot water heating: gas storage tank, tankless gas, OR condensing tankless gas
    •    All Electric (resistance):
             o Space heating: electric baseboard
             o Hot water heating: electric storage tank
    •    All Electric (heat pump):
             o Space heating: air source heat pump
             o Hot water heating: heat pump
    •    Hybrid (Gas/Electric):
            o Space heating: any option (opposite fuel source to hot water heater)
            o Hot water heating: any option (opposite fuel source to space heating)

The results show the GHGI for the lowest ICC result for each heating system configuration. As such, other
ECMs were not held constant and, depending on the modelled results available, may have led to some
anomalies in the results. For example, GHGI can reasonably be expected to drop with increasing steps when
mechanical system configurations are constant. However, variations in the other ECMs might result in lower
GHGIs at lower steps. The accompanying analysis tool contains the full list of ECMs for each result.

                                                      11
Key assumptions include the following:

   •     Base costs: Details on ECM costs can be found in the original Metrics Report. Part 9 costs calculated
         for all Steps include estimates for the Energy Advisor services and blower door tests that are required
         to comply with the Step Code. ECM costs are represented as incremental cost increases ($) over the
         ECMs that were defined for each baseline archetype (i.e. baseline costs are set at $0).
   •     Life cycle cost: NPV calculations apply a real discount rate of 3% and assume a time horizon of 20
         years to represent a consistent lifespan of major component units associated with the analysis.
   •     Emissions intensity (electricity): The GHG intensity of electricity was assumed to be 0.0000117
         tonnes CO2e/kWh, as per Canada’s 2016 National Inventory Reporti.
   •     Emissions Intensity (natural gas): The GHG intensity of natural gas was assumed to be 49.87
         kgCO2e/GJ (0.000180 tonnes CO2e/kWh), as per the 2016/2017 BC Best Practices Methodology for
         Quantifying GHG Emissionsii.
   •     Emissions Intensity (renewable natural gas): The GHG intensity of renewable natural gas was
         assumed to be 0.29 kgCO2e/GJ (0.000001044 tonnes CO2e/kWh), as per the 2016/2017 BC Best
         Practices Methodology for Quantifying GHG Emissions.
   •     Projected energy prices (electricity): Estimates for electricity were based on a review of BC Hydro
         rate projections. Pricing includes rates for Part 9 (Tier 1 and Tier 2) and Part 3. Total electricity price
         includes base energy fee, rate rider fee, and GST.
   •     Projected energy prices (natural gas): Estimates for natural gas were based on a review of Fortis BC
         rate projections and include the carbon tax, which is assumed to increase to $50/tCO2e in 2022. Pricing
         includes rates for Part 9 and Part 3. Total natural gas price includes delivery fee, storage & transport
         fee, midstream commodity fee, carbon tax, municipal operating charge, clean energy levy, GST, and
         PST.
   •     Projected energy prices (renewable natural gas): Pricing for renewable natural gas was based on
         the natural gas pricing above. For renewable natural gas, adjusted delivery costs were provided by
         FortisBC. Additionally, the carbon tax was not applied to RNG.

Notes:
         •   Tables showing the full energy price projections used in the Metrics Report are included in
             Appendix B
         •   The Metrics Report pricing methodology assumed a single increase to the Carbon Tax to $50/
             tCO2e in 2022. The Province of British Columbia has since adjusted their Carbon Tax pricing to
             raise the price $5/ tCO2e each year starting April 1st, 2018 until it reaches $50/ tCO2e in 2021. The
             Metrics Report costing results were not adjusted in this study to reflect this discrepancy.

                                                         12
Part 3 Buildings – Methodology

The original analysis of Part 3 buildings in the Metrics Report was conducted using EnergyPlus v8.6, using
Building PathFinder to allow for an analysis of the large data sets generated by parametric analysis and the
identification of the relationships between different design parameters and their outcomes. Building
archetypes selected for this study include Low-Rise MURB, High-Rise MURB, Office and Retail, and modelled
to meet the Total Energy Use Intensity (TEUI) and Thermal Energy Demand Intensity (TEDI) performance
requirements for Part 3 buildings. Base archetypes are described below, with additional details provided in
Appendix C.

 Archetype                    Details
 Low-Rise MURB                 Variable characteristics to represent the range of MURBs in the marketplace,
                               90% suites, 10% common area, 18,000m2

 High-Rise MURB                Variable characteristics to represent the range of MURBs in the marketplace,
                               90% suites, 10% common area, 18,000m2

 Commercial Office             Market, 18,200m2, 10 storeys, 790 people, 155 parking spaces

 Retail (big box)              Market, 4,500m2, 1 storey, 150 people

The Metrics Report also generated a sizeable dataset of modelled Part 3 buildings. The results from Climate
Zone 4 were used as the basis for the analysis. However, modelled results for Part 3 were somewhat more
restricted and did not include all configurations needed for this study. As such, a summary file was built by
drawing results (where possible) from the modelled Part 3 end use files. Where a configuration did not exist,
simple calculations were applied to convert a modelled result to represent the desired configuration. This
methodology is described for each studied configuration and archetype in Appendix D. These results were
then used to construct comparison matrices for each Part 3 building archetype to show the GHG intensities
of the Step Code for a range of mechanical system configurations. As above, these configurations included:
   •    All Gas
   •    All Electric (resistance)
   •    All Electric (heat pump)
   •    Hybrid (Gas/Electric)

Construction costs, and consequently NPV and carbon abatement costs, are not available for Part 3
scenarios developed by converting Metrics Report results (e.g. all electric scenarios for MURBs and Office, as
noted in Appendix D). Key assumptions are consistent with those defined for Part 9 above, except as
specified below:

   •    Base costs: Details on base costs for Part 3 buildings can be found in the original Metrics Report.
        Part 3 costs calculated for all Steps include estimates for airtightness testing. Costs are represented
        as incremental cost increases ($) over the defined baseline archetype (i.e. baseline costs are set at
        $0).

                                                      13
4   ANALYSIS

      Understanding Building Emissions Performance

Prior to delving into the analysis, it is important to set a context for how low- or zero emissions buildings are
currently being considered by local governments in BC.

In October 2018, the Intergovernmental Panel on Climate Change (IPCC) issued a Special Report on Global
Warming of 1.5oC, which demonstrated the need to limit global warming to 1.5C in order to avoid the worst
and most costly impacts of climate change. This was in turn determined to require a rapid transition across
all sectors to achieve 40-60% GHG emissions by 2030, and a net zero level of emissions by mid-century.
Several cities have begun to mobilize to respond to this call – in British Columbia alone, 16 municipalitiesiii
have declared climate emergencies and several are working on plans for bold action to try to rapidly reduce
emissions. Buildings represent a significant contributor to community emissions (often in the range of 50%
or more) and have therefore been a key focus in climate action planning, including both existing buildings
and new building construction. CleanBC has also recognized this imperative in setting a bold vision to make
better buildings across the province, envisioning “a future where buildings produce no polluting emissions
at alliv.”

In creating the Step Code, British Columbia signaled their commitment to a net-zero energy-ready future by
2032 – i.e. one in which all buildings are “designed and built to a level of performance such that it could, with
the addition of solar panels or other renewable energy technologies, achieve net-zero energy
performance”v. The City of Vancouver’s Zero Emissions Building Plan (ZEBP) takes an additional step in
setting both energy efficiency and GHG intensity performance targets to support their goals of achieving
net-zero emissions by 2030. Vancouver’s ZEBP highlights the need for new buildings to achieve near zero
emissions as soon as possible to avoid costly and challenging retrofits in the futurevi. ZEBP also serves as the
guiding document shaping building policy in Vancouver and has led to the inclusion of GHGI performance
limits. Table 1 below highlights the stepped GHGI targets for various building types from Vancouver’s Green
Buildings Policy for Rezonings (Part 3 buildings) and the ZEBP.

                                                       14
Table 1: City of Vancouver ZEBP GHGI Targetsvii

  Building        2007      Current Current             2016         2016      2020      2020       2025     2025
 Archetype      Baseline     Bylaw Rezoning            Bylaw       Rezoning   Bylaw    Rezoning    Bylaw   Rezoning

 Detached
                   23.0       12.0          -            -            -        7.0            -      0           -
 Housing
  Low-Rise
                    -         12.5         10.5         5.5          5.0        -            4.5     0           0
   MURB
  High-Rise
                    -         20.0         16.5        20.0          6.0       6.0           5.0    5.0          0
   MURB
   Office           -          9.5         7.5          9.5          3.0       3.0           1.0     0           0

    Retail                                                           3.0

Vancouver’s current targets are approaching those for 2020, which range from 1.0 to 7.0 kgCO2e/m2.y. By
2025, the City will require all new construction to be designed to a zero emissions level of performance.
Note: following a Memorandum of Understanding with FortisBC, the City established an Alternative
Compliance Pathway for Energy and GHG Reductions to allow projects to pursue a higher level of energy
efficiency performance in lieu of achieving a GHGI target.

Given its alignment with the intentions of CleanBC, the City of Vancouver’s ZEBP serves as a suitable
reference point against which to compare building operational GHG intensities. To begin to understand the
current emissions performance of BC’s buildings, Tables 2 and 3 below show the GHG intensities and
resultant absolute emissions for the baseline buildings used in the Metrics Report. These baseline
archetypes show a significant gap between current performance and the zero emissions vision that both
CleanBC and the City of Vancouver have set.

Table 2: Metrics Report Baseline Archetypes (Part 9)

                                GHGI               Building Area
 Building Archetype                                                        Space Heating Fuel DHW Heating Fuel
                            (kgCO2e/m2.y)               (m2)

    MURB (10 Unit)                   3.9                 1,655                 Electricity         Natural Gas

      Rowhouse                    11.4                   1,008                Natural Gas          Natural Gas

       Quadplex                      7.6                     514               Electricity         Natural Gas

       Large SFD                  12.1                       511              Natural Gas          Natural Gas

     Medium SFD                   12.4                       237              Natural Gas          Natural Gas

       Small SFD                  18.7                       102              Natural Gas          Natural Gas

                                                             15
Table 3: Metrics Report Baseline Archetypes (Part 3)

                                GHGI               Building Area
 Building Archetype                                                  Space Heating Fuel DHW Heating Fuel
                            (kgCO2e/m2.y)               (m2)

   Low-Rise MURB                   9.3                 18,000              Electricity          Natural Gas

   High-Rise MURB                  9.3                 18,000              Electricity          Natural Gas

         Office                   11.6                 18,209             Natural Gas           Natural Gas

         Retail                   10.7                 4,502              Natural Gas           Natural Gas

The City of Vancouver’s GHGI targets will be used as a frame of reference for the subsequent analysis in this
report, and to understand whether the existing Step Code performance targets are enough to drive down
building operational emissions towards near zero emissions at the highest Steps. Lower Steps of the Step
Code will be compared to Vancouver’s targets for 2016 or 2020, and Higher Steps will be compared to
Vancouver’s zero emissions target for 2025.

      Building Emissions – Part 9

GHG intensities for the different Part 9 archetypes heating system scenarios analyzed for this study are
shown in Figures 1 through 6 below. Each figure shows the GHGI for the lowest ICC result for each scenario
available from the Metrics Report, as well as a comparison with the relevant City of Vancouver GHGI target
to provide context. Detailed information on each of these results is included in Appendix E. It should be
noted that any scenarios without values shown in the figures below indicate scenarios where the Metrics
Report dataset did not include any corresponding results.

Broadly speaking, results show that the Step Code alone does not force designers to select one mechanical
system over another. For most archetypes, Steps 1 through 5 can be achieved with any of the widely used
space and domestic hot water heating systems available on the market. As a result, there is a significant
difference in the GHGIs that could manifest at each step. For example, the GHGI for a Large SFD at Step 5
using an electric heat pump is 93% lower than the Step 5 GHGI for Large SFD with all-gas heating systems.
However, for smaller building archetypes (e.g. Small SFD and Quadplex), the absence of modelled results for
Step 5 for either all-gas or all-electric resistance systems does indicate that the Step 5 MEUI target begins to
restrict equipment selection towards higher efficiency systems (such as heat pumps) to meet the energy
performance targets.

Results also indicate that the Step Code is a successful driver for lower operational emissions in buildings
with gas-based systems. For example, a 10-unit MURB modelled to achieve Step 5 with gas-based systems
result in a 27% reduction in GHGI over those modelled to Step 1. While this is a positive trend, homes with
gas-based heating systems have GHGIs typically higher than the City of Vancouver reference (except for 10-
Unit MURB (see note below) and the highest Steps). Results show that hybrid systems are more likely to
meet or exceed the City of Vancouver reference GHGI.

                                                       16
However, the Step Code is not the main driver in lowering operational emissions in buildings with electric-
based systems (especially heat pumps). For these systems, most archetypes (except Small SFD) have GHGIs
below 1 kgCO2e/m2.y for all Steps. This means that regardless of the Step selected, electric-based systems
achieve very low emissions performance.

It should be noted that there are a small number of “outlier” results that do not follow the downward GHGI
trend with increasing Steps seen with most scenarios. As noted in Section 3.2, other ECMs (e.g. airtightness,
windows, R-values) were not held constant in this modelling exercise. Combined with the limitations the
Metrics Report placed on the modelled results (see Appendix A), this has created a few irregularities in the
results. For example, the all-gas system scenario for the 10-Unit MURB archetype at Step 2 is significantly
higher than the other Steps. A contributing factor to this result is that the Metrics Report results did not
allow gas furnace space heating systems for the 10-Unit MURB results – only combination space/DHW
heating systems – limiting the results available for this study. Examining the other ECMs for the Step 2 result
compared to the other Steps provides further insights and reveals that the Step 2 result assumes lower-
performing envelope components than the Step 1 results. For example:

   •   Wall R-Value: Step 1 = 24, Step 2 = 16
   •   Ceiling R-Value: Step 1 = 70, Step 2 = 40
   •   Window Option: Step 1 = high performance triple paned, Step2 = double paned (baseline selection)
   •   Ventilation Heat Recovery: Step 1 = 84%, Step 2 = 0%
The fact that Step 2 can be reached with much lower envelope measures suggests that the Step 1 results are
in essence ”over-performing” in terms of envelope performance, and therefore do not provide a reasonable
estimate of Step 1 performance.

                                                      17
9.0

                        8.0

                        7.0
   GHGI (kgCO2e/m2.y)

                        6.0

                        5.0

                        4.0

                        3.0

                        2.0

                        1.0

                        0.0
                                             1                   2                    4                      5

                               Electric Heat Pump     Electric Resistance    Gas     Hybrid       COV GBP for Rezoning

Figure 1: GHGI vs Step Code Trends – Multi-Unit Residential Building (10 Unit)

                        12.0

                        10.0
   GHGI (kgCO2e/m2.y)

                         8.0

                         6.0

                         4.0

                         2.0

                         0.0
                                         1                 2                3                 4                  5

                                      Electric Heat Pump         Gas        Hybrid        COV GBP for Rezoning

Figure 2: GHGI vs Step Code Trends – Rowhouse

                                                                            18
12.0

                        10.0
   GHGI (kgCO2e/m2.y)

                         8.0

                         6.0

                         4.0

                         2.0

                         0.0
                                         1               2                3               4                5

                               Electric Heat Pump   Electric Resistance    Gas   Hybrid       COV GBP for Rezoning

Figure 3: GHGI vs Step Code Trends – Quadplex

                        14.0

                        12.0

                        10.0
   GHGI (kgCO2e/m2.y)

                         8.0

                         6.0

                         4.0

                         2.0

                         0.0
                                         1               2                3               4                5

                               Electric Heat Pump   Electric Resistance    Gas   Hybrid       COV ZEBP 2020 Bylaw

Figure 4: GHGI vs Step Code Trends – Large Single-Family Dwelling

                                                                          19
14.0

                        12.0

                        10.0
   GHGI (kgCO2e/m2.y)

                         8.0

                         6.0

                         4.0

                         2.0

                         0.0
                                         1                 2                     3                    4               5

                                  Electric Heat Pump       Electric Resistance         Gas      Hybrid       COV ZEBP 2020 Bylaw

Figure 5: GHGI vs Step Code Trends – Medium Single-Family Dwelling

                        20.0

                        18.0

                        16.0

                        14.0
   GHGI (kgCO2e/m2.y)

                        12.0

                        10.0

                         8.0

                         6.0

                         4.0

                         2.0

                         0.0
                                         1                 2                     3                    4               5

                               Electric Heat Pump      Electric Resistance       Gas         Hybrid       COV ZEBP 2020 Bylaw

Figure 6: GHGI vs Step Code Trends – Small Single-Family Dwelling

                                                                             20
Building Emissions – Part 3

GHG intensities for the various Part 3 archetypes for each heating system scenario are shown in Figures 7
through 10 below. As above, GHGIs for each scenario is shown next to the relevant City of Vancouver GHGI
target for context. Detailed information on each of these results is included in Appendix F.

As with Part 9 buildings, results show that the Step Code energy performance targets for Part 3 buildings are
not a driver for mechanical system selection: all Steps can be achieved with any of the heating systems.
Consequently, results show a wide range of possible GHGIs at each Step, depending on the mechanical
system that is used. For example, GHGI at the highest Step is on average 87% lower for heat pump systems
versus all-gas systems across all Part 3 archetypes. Results also show that gas-based and most hybrid-based
systems result in higher GHGIs than Vancouver’s GHGI targets, while electric-based heating systems will
reduce emissions to easily meet Vancouver’s current targets. These results demonstrate that the Step Code
alone does not drive building performance to meet low or zero-emissions performance.

However, the Step Code is successful in driving down emissions in Part 3 building archetypes, regardless of
heating system type. The difference is more pronounced in gas-based systems, which see an average GHGI
reduction of 44% between Step 1 and the highest Step. In contrast, electric heat pump systems only see an
average 13% reduction between Step 1 and the highest Step. Additionally, GHGI falls below 1 kgCO2e/m2.y
for all Steps when electric heat pump systems are applied – in other words, electric heat pump systems
achieve very low GHGIs, independent of the level of energy efficiency of the Step Code that is achieved.

 16.0

 14.0

 12.0

 10.0

  8.0

  6.0

  4.0

  2.0

  0.0
                   1                     2                     3                     4

           Electric Heat Pump    Electric Resistance    Gas    Hybrid     COV GBP for Rezoning

Figure 7: GHGI vs Step Code Trends – Low-Rise MURB

                                                       21
18.0

 16.0

 14.0

 12.0

 10.0

  8.0

  6.0

  4.0

  2.0

  0.0
                   1                      2                        3                   4

          Electric Heat Pump      Electric Resistance        Gas   Hybrid   COV GBP for Rezoning

Figure 8: GHGI vs Step Code Trends – High-Rise MURB

 12.0

 10.0

  8.0

  6.0

  4.0

  2.0

  0.0
                       1                                2                          3

          Electric Heat Pump      Electric Resistance        Gas   Hybrid   COV GBP for Rezoning

Figure 9: GHGI vs Step Code Trends – Office

                                                            22
10.0

  9.0

  8.0

  7.0

  6.0

  5.0

  4.0

  3.0

  2.0

  1.0

  0.0
                       1                                 2                          3

           Electric Heat Pump      Electric Resistance        Gas   Hybrid   COV GBP for Rezoning

Figure 10: GHGI vs Step Code - Retail

        Incremental Construction Costs – Part 9

In addition to GHGIs, incremental construction costs (ICCs) were also analyzed to look for trends across the
heating system scenarios. ICC is defined as a percentage increase over the defined archetype baseline,
which has set in the original Metrics Report results. Results for the ICC analysis are presented in Figures 11
to 16 below, with additional financial implications (including effective 20-year NPV, carbon abatement cost
and annual effective energy costs) presented in Appendix E.

In general, ICCs show an upward trend with increasing Steps, with a significant increase from Step 4 to Step
5 for most archetypes and most heating system types. For all archetypes, hybrid and electric resistance-
based heating systems provided the lowest ICCs at lower Steps. Electric heat pumps show a significant
premium over other heating systems at lower Steps, but by Step 5 are typically in the same range or lower
than other heating system options. This is likely due to the fact that higher efficiency heat pumps require
less stringent envelope measures to meet Step 5 performance limits.

ICCs for gas-based heating systems varied depending on building archetype, indicating that archetype is an
important factor in determining the affordability of gas-based heating systems. For example, ICCs for 10-
Unit MURBs and Quadplex archetypes are in the same range as the electric heat pump option at lower
Steps, but are aligned with the lower-priced electric resistance and hybrid options for other archetypes.

In terms of operating costs, results also show that energy costs are lowest for all gas or all heat pump
options due to the low cost of natural gas and the high efficiency of heat pumps, respectively (see Appendix
E). Conversely, the use of electric resistance heating reduces incremental construction costs (especially
when compared to heat pumps) but raises operating costs. Hybrid systems, either combined heat

                                                             23
pump/electric resistance or gas/electric, may provide a reasonable balance of construction and operating
costs, while providing significant GHG emissions reductions.

                                    7%

                                    6%
   Incremental Construction Costs

                                    5%
         (% Over Baseline)

                                    4%

                                    3%

                                    2%

                                    1%

                                    0%
                                          1                   2                     4              5

                                         Electric Heat Pump   Electric Resistance   Gas   Hybrid

Figure 11: ICC versus Step Code - Multi-Unit Residential (10 Unit)

                                                                       24
12%

                                    10%
   Incremental Construction Costs
         (% Over Baseline)

                                    8%

                                    6%

                                    4%

                                    2%

                                    0%
                                          1                2                   3               4            5

                                                     Electric Heat Pump     Gas       Hybrid

Figure 12: ICC versus Step Code – Rowhouse

                                    12%

                                    10%
   Incremental Construction Costs
         (% Over Baseline)

                                    8%

                                    6%

                                    4%

                                    2%

                                    0%
                                          1                2                   3               4            5

                                          Electric Heat Pump    Electric Resistance      Gas       Hybrid

Figure 13: ICC versus Step Code – Quadplex

                                                                          25
8%

                                    7%
   Incremental Construction Costs

                                    6%
         (% Over Baseline)

                                    5%

                                    4%

                                    3%

                                    2%

                                    1%

                                    0%
                                          1                   2                3               4            5

                                              Electric Heat Pump   Electric Resistance   Gas       Hybrid

Figure 14: ICC versus Step Code – Large Single-Family Dwelling

                                    12%

                                    10%
   Incremental Construction Costs
         (% Over Baseline)

                                    8%

                                    6%

                                    4%

                                    2%

                                    0%
                                          1                    2                 3             4            5

                                              Electric Heat Pump   Electric Resistance   Gas       Hybrid

Figure 15: ICC versus Step Code – Medium Single-Family Dwelling

                                                                            26
20%

                                    18%
   Incremental Construction Costs

                                    16%

                                    14%
         (% Over Baseline)

                                    12%

                                    10%

                                    8%

                                    6%

                                    4%

                                    2%

                                    0%
                                          1                2               3               4            5

                                                      ElecHP    Electric   Gas   Hybrid

Figure 16: ICC versus Step Code – Small Single-Family Dwelling

                   Incremental Construction Costs – Part 3

ICCs were also analyzed to the extent possible for Part 3 buildings and presented in Figures 17 to 20 below.
With the exception of retail archetype with electric resistance heating, costs for electric heating scenarios
were not available from the Metrics Report results and therefore are not presented below. Additional
financial implications, including effective 20-year NPV, carbon abatement cost and annual effective energy
costs, are also presented in Appendix F.

For the gas and hybrid scenarios presented in the figures below, ICC generally shows an upward trend with
increasing Steps. However, premiums are low for all Steps and archetypes at less than a 2% incremental
increase over the defined baseline. For example:

      •                     Low-Rise MURBs built with gas or hybrid systems are expected to:
                               o Provide ICC savings over the defined baseline at Steps 1 and 2
                               o Cost less than 1% ICC premium to reach Step 4

      •                     Offices built with gas or hybrid systems are expected to:
                                o Provide ICC savings over the defined baseline for all Steps

      •                     Low-Rise MURBs built with electric resistance, gas, or hybrid systems are expected to:
                               o Require similar small premiums for Steps 1 and 2 regardless of mechanical system
                               o Cost less than 2% ICC premium to reach Step 3

To provide some context for understanding costs for the electric heat pump scenarios, findings from
Toronto’s Zero Emissions Buildings (ZEB) Framework can be notedviii. The framework includes four tiers of
                                                   27
energy performance targets alongside GHGI limits, which drive mechanical systems towards heat pumps at
higher tiers. For most archetypes, ICC for Toronto archetypes trends upward through Tier 3, but then drops
at Tier 4. This can be attributed to the fact that Tier 3 buildings were modelled to use natural gas boilers to
deliver some of the heating load, which were made unnecessary at Tier 4 (which used only small back-up
gas systems). Similar trends can be expected with Step Code buildings, as the improved envelope
characteristics of Step 3 or 4 buildings will reduce sizing requirements, and therefore costs, of mechanical
systems.

  1.0%

  0.8%

  0.6%

  0.4%

  0.2%

  0.0%

 -0.2%

 -0.4%

 -0.6%

 -0.8%
                   1                      2                      3                      4

                                              Gas    Hybrid

Figure 17: ICC versus Step Code – Low-Rise MURB

                                                      28
2.0%

  1.5%

  1.0%

  0.5%

  0.0%

 -0.5%

 -1.0%
                    1                      2                  3       4

                                               Gas   Hybrid

Figure 18: ICC versus Step Code - High-Rise MURB

                        1                            2            3
  0.0%

 -0.1%

 -0.1%

 -0.2%

 -0.2%

 -0.3%

 -0.3%

 -0.4%

                                               Gas   Hybrid

Figure 19: ICC versus Step Code – Office

                                                      29
2.0%

 1.8%

 1.6%

 1.4%

 1.2%

 1.0%

 0.8%

 0.6%

 0.4%

 0.2%

 0.0%
                       1                                  2                        3

                                    Electric Resistance       Gas   Hybrid

Figure 20: ICC versus Step Code – Retail

        Absolute Emissions

While GHGI numbers provide a good means of comparing emissions performance across a range of
building types and sizes, absolute emissions (i.e. the total emissions emitted each year) is also an important
metric to understand. Using an absolute emissions metric helps to show the impact of mechanical system
choice on the Province’s total emissions and by extension their ability to meet their CleanBC goals.

Absolute emissions versus Step achieved is shown for Part 9 10-Unit MURB, Small SFD, and Part 3 Office
archetypes in the figures below. Tables summarizing absolute emissions for all archetypes are given in
Appendix G and Appendix H. The results show that the impacts of heating system choice can be quite
significant, especially when multiplied by building lifetime. For example, assuming a 50-year lifetime:

    •    10-Unit MURB (1655 m2 area) built to Step 1:
            o Gas-based heating systems will emit approximately 315 tonnes CO2e more than a building
                 with electric heat pump heating systems
            o Hybrid-based heating systems will emit approximately 250 tonnes CO2e more than a
                 building with electric resistance heating systems

    •    10-Unit MURB (1655 m2 area) built to Step 5:
            o Gas-based heating systems will emit approximately 220 tonnes CO2e more than a building
                 with electric heat pump heating systems
            o Hybrid-based heating systems will emit approximately 205 tonnes CO2e more than a
                 building with electric resistance heating systems

                                                          30
•                         Office (18,209 m2 area) built to Step 1:
                                       o Gas-based heating systems will emit approximately 8,145 tonnes CO2e more than a building
                                            with electric heat pump heating systems
                                       o Hybrid-based heating systems will emit approximately 1,860 tonnes CO2e more than a
                                           building with electric resistance heating systems

         •                         Office (18,209 m2 area) built to Step 5:
                                       o Gas-based heating systems will emit approximately 5,775 tonnes CO2e more than a building
                                            with electric heat pump heating systems
                                       o Hybrid-based heating systems will emit approximately 2,150 tonnes CO2e more than a
                                            building with electric resistance heating systems

                                   16,000

                                   14,000
   Absolute Emissions (kgCO2e/y)

                                   12,000

                                   10,000

                                    8,000

                                    6,000

                                    4,000

                                    2,000

                                       -
                                                   1                   2                    4                5

                                                 Electric Heat Pump   Electric Resistance   Gas   Hybrid

Figure 21: Absolute Emissions - Part 9 10-Unit MURB (1,655 m2)

                                                                               31
Absolute Emissions (kgCO2e/y)   2,500

                                   2,000

                                   1,500

                                   1,000

                                    500

                                      -
                                               1               2                3               4                5

                                               Electric Heat Pump   Electric Resistance   Gas       Hybrid

Figure 22: Absolute Emissions - Part 9 Small SFD (102 m2)

                                   200,000

                                   180,000
   Absolute Emissions (kgCO2e/y)

                                   160,000

                                   140,000

                                   120,000

                                   100,000

                                    80,000

                                    60,000

                                    40,000

                                    20,000

                                           -
                                                     1                              2                        3

                                               Electric Heat Pump   Electric Resistance   Gas       Hybrid

Figure 23: Absolute Emissions - Part 3 Office (18,209 m2)

                                                                             32
Using Renewable Natural Gas

As noted in the introduction, the Province’s CleanBC program commits British Columbia to increasing
renewable natural gas (RNG) supply to a minimum of 15% by 2030. To understand the impact of this
increasing proportion of lower carbon RNG on GHGI results, the analysis above was re-run with an
assumption of 15% RNG (in comparison to 100% natural gas). Select results from this analysis are presented
in Table 4 and Table 5 below. GHGI from the initial analysis for both the gas and hybrid systems (see
Sections 4.2, 4.3, Appendix E and Appendix F) is shown alongside the adjusted GHGI with 15% RNG. Full
results for each archetype are presented in Appendix I.

The results of this analysis show that GHG intensity can be expected to drop in buildings with gas-based
space and DHW heating systems by 11% to 14% with 15% RNG content, as compared to systems operating
with current natural gas supply. For example:

   •    Table 4 shows GHGI reducing 14% (from 8.64 kgCO2e/m2.y to 7.41 kgCO2e/m2.y) for a Step 3 home
        with all gas heating and DHW;

   •    Table 5 shows GHGI reducing 11% (from 3.67 kgCO2e/m2.y to 3.26 kgCO2e/m2.y) for a Step 1 home
        with hybrid gas/electric heating and DHW

Further increases in RNG supply would continue these trends and further reduce emissions intensities.

Table 4: Part 9 – Medium SFD RNG Analysis

                        Greenhouse Gas Intensity (GHGI) - kgCO2e/m2.y

                                                 %             Hybrid                         %
         Gas – Original      Gas w/                                            Hybrid
 Step                                       difference    Gas/Electric mix –             difference
           Analysis           RNG                                              w/ RNG
                                             in GHGI      Original Analysis               in GHGI
   1
              12.40           10.61           -14%               4.99           4.36        -13%

   2
               9.98            8.54           -14%               4.96           4.33        -13%

   3
               8.64            7.41           -14%               4.88           4.25        -13%

   4
               6.79            5.83           -14%               3.90           3.41        -13%

   5
               3.73            3.23           -13%               3.34           2.91        -13%

                                                     33
You can also read