64% Reduction in the Carbon Impact of the SOPREMA Building in Dartmouth (NS)

Since 2018, SOPREMA Canada has been redoubling its efforts to quantify and reduce its carbon impact in several areas of its activities.

In line with its commitment to fighting climate change, several energy efficiency projects are implemented each year at SOPREMA sites across the country. In addition to ensuring consistency with this commitment, these projects are generally synonymous with creating value for the company by contributing to the reduction of energy consumption, including the cost and carbon impact of operations. These projects are also a growing source of pride for our employees. 
 
To inspire its stakeholders to embrace the energy transition, SOPREMA Canada is showcasing one of its successful projects. This case study looks at an energy efficiency project at the SOPREMA building located in Dartmouth (NS), completed in February 2024. It covers the different phases of the project, from the impact of moving operations to a new building in 2021 to the integration of a photovoltaic solar roof and a thermal solar wall in 2024. Results related to energy consumption, cost and carbon impact are also presented.

Context

SOPREMA’s 20,000 ft² (⇔ 1,858 m²) building in Dartmouth (NS) features both a 5,000 ft² (⇔ 464.5 m²) sales office and a 15,000 ft² (⇔ 1,395.5 m²) warehouse. A dozen employees dedicated to the distribution and sale of SOPREMA and RESISTO products for the province of Nova Scotia and the Eastern Canada region work there. The company has been operating in the area since 1985. A wide selection of products passes through the warehouse, including a wide variety of liquid products requiring indoor storage protected from the elements with a required ambient temperature between 18 and 25 °C. Unlike other provinces, Nova Scotia’s energy production is based on several different energy sources, which requires a brief explanation.

Sources of Electricity

The electricity supplier for the SOPREMA site in Dartmouth is Nova Scotia Power. In contrast to other provinces, electricity production comes mainly from fossil fuels (76%) and to a lesser extent from renewable sources (24%). Electricity production from fossil fuels mainly relies on coal, coke, oil, and natural gas power plants. Electricity generation from renewable energies is based on hydropower, wind, and biomass. In contrast, electricity generation in Québec is mainly from renewable sources (99.6%) and only marginally from fossil fuels (0.4%). Electricity production from renewable energies is mainly based on hydropower, wind, solar, and biomass ^[1].

When comparing the two provinces, the carbon footprint of electricity generation in Nova Scotia is 0.66 kg CO₂eq./kWh while it is 0.0013 kg CO₂eq./kWh in Québec ^[2]. This means that the carbon impact of electricity generation in Nova Scotia is 510 times higher than in Québec.

Other Fuel Sources

The natural gas supplier for the SOPREMA site in Dartmouth is Eastward. The carbon impact of natural gas in Nova Scotia is similar to the Canadian average, with a carbon footprint of 1.93 kg CO₂eq./m³. For other fuels, the carbon impact is based on the Canadian average for fuel oil, which represents 0.003 kg CO₂eq./L, while for propane it’s 0.002 kg CO₂eq./L ^[3].

Scope of the Study

The analysis is mainly based on the impact of the different phases of the project and shows the evolution of the building’s performance in relation to the completion of these different phases. The values analyzed are based on real and theoretical data relating to energy consumption (kWh), cost ($) and carbon footprint (tCO₂eq.), specifically in relation to electricity, fuel oil, natural gas, and propane. As an essential component of building operations, lift trucks are also included. Technology maintenance costs are also considered. The items included and excluded from the analysis are detailed below.

Items Included

Scope 1 – Direct emissions from fossil fuels (e.g., fuel oil, natural gas, and propane consumption). Scope 2 – Indirect energy-related emissions (e.g., consumption of electricity supplied by Nova Scotia Power). Referring to operational carbon, this essentially includes the energy consumed by building operations and the lift trucks used to carry out these operations.

Items Excluded

Scope 1 – Direct emissions from fossil fuels and refrigerants (e.g., gasoline, diesel, and refrigerant). Scope 3 – Indirect emissions from fossil fuels used for input extraction, input manufacturing, input transportation, input installation, residual materials, employee travel, and production, extraction, and distribution of fuels for building and lift truck consumption. Referring to embodied carbon, this essentially encompasses energy, refrigerant losses, waste, and other substances that have a carbon impact upstream and downstream of building operations.

Project Description

The project is divided into two distinct phases aimed at improving the energy performance of the building. Phase 1 included the relocation of SOPREMA’s operations in Dartmouth to a new building (2021), then Phase 2 consisted of the addition of a photovoltaic solar roof and a solar thermal wall (2024). The following table provides an overview of some of the highlights from the reference year and the two phases of the project.

Summary of the Project Phases

Reference Year 
Former Building (2018)

• Former building was rented.

• Building area of approximately 10,000 ft² (⇔ 929 m²).

• Oil heating system.

• Halogen and fluorescent lighting system.

• Deficient building envelope.

• Propane-powered lift trucks (100% of equipment).

Phase 1  
New Building (2021)

• Moving to a New Building.

• Building area of 20,000 ft² (⇔ 1,858 m²).

• Natural gas heating system.

• LED lighting system.

• Building envelope in compliance with the National Energy Code of Canada for Buildings 2017.

• Mainly electric lift trucks (66% of equipment).

Phase 2 
Energy Efficiency Project (2024)

• Addition of a photovoltaic solar roof totaling 8,000 ft² (⇔ 743.2 m²) with a capacity of 75.7 kW DC (84.8 MWh/year).

• Addition of a solar thermal wall totaling 1,000 ft² (⇔ 92.9 m²) with a capacity of 10,000 cfm.

• Investment value (total): $233,319

Reference Year – Former Building (2018)

The first carbon balance was carried out in 2018, thus constituting the reference year for the building. In 2018, operations were carried out in a rented building. The higher energy consumption despite a smaller footprint and lower activity levels could be explained by a less efficient building envelope compared to the requirements of the new energy codes. The building was heated by an oil boiler and operations carried out using propane-powered lift trucks. The lighting system consisted of energy-intensive halogen and fluorescent fixtures.

At that time, the building was among SOPREMA’s warehouses with the highest carbon impact in Canada. It accounted for 6% of energy consumption, 8% of energy costs, and 13% of the carbon impact of all SOPREMA’s Canadian warehouses. It thus became a priority site in the strategy for reducing GHG emissions in relation to fossil fuel consumption (Scope 1) and electricity use (Scope 2).

The 2018 former building’s reference points are as follows:

• Energy consumption of 327,904 kWh.

• Energy purchase cost of $36,777.

• Carbon footprint of 133 tCO₂eq.

Phase 1 – New Building (2021)

For the first phase of the project, operations moved to a new building at the end of 2020. This is a new construction that complies with the National Energy Code of Canada for Buildings 2017, with a much-improved building envelope compared to the former building (2018). The natural gas heating system made it possible to completely eliminate the need for fuel oil that was previously used, making the new heating system more efficient and less polluting. Furthermore, the use of an LED lighting system instead of halogen and fluorescent fixtures in the former building (2018) increased energy efficiency by reducing the electricity consumption required for lighting. Another improvement was replacing propane gas lift trucks with electric lift trucks. The project greatly enhanced operational efficiency in addition to increasing employee comfort. No investment grant was allocated for this phase of the project.

Phase 2 – Energy Efficiency Project (2024)

In the second phase of the project, the building was fitted with a photovoltaic solar roof dedicated to the production of electricity as well as a thermal solar wall for the capture of heat on the facade. The photovoltaic solar roof with a capacity of 75.7 kW DC (84.8 MWh/year) helps reduce electricity consumption that mainly comes from fossil energy sources. The solar thermal wall with a capacity of 10,000 cfm makes it possible to decrease the consumption of natural gas also derived from fossil energy sources.

The total investment is $233,319, including non-repayable grants from various Efficiency Nova Scotia programs. Corresponding to less than 10% of the value of the investment, these grants amount to $23,557, or $8,098 for the photovoltaic solar roof, which represents 4% of the value of this measure ^[4] and $15,459 for the thermal solar wall, which is 35% of the value of this measure ^[5]. The installation was completed in February 2024. Details of the project technologies are given in the table below.

Systems Overview

Photovoltaic Solar Roof

With an area of 8,000 ft² (⇔ 743.2 m²), the solar roof has 172 photovoltaic panels, which provides an annual electricity production capacity of approximately 75.7 kW DC (84.8 MWh/year). The solar roof represents almost 40% of the building’s roof surface. The selected system is the VSUN 440-144BMH-DG bifacial model with SMA Sunny Tripower CORE1 62-US inverter. Each panel, measuring 83.5 in × 41.3 in × 1.4 in (2,122 mm × 1,048 mm × 35 mm), has a maximum power output of 445 W and a module efficiency of 20.01%. The materials and labour warranty period is 12 years while the linear power warranty is 30 years.

The panels rest on a support system comprising 352 SOPRASOLAR FIX EVO TILT polyamide pedestals. These are adjustable in height and mechanically attached to a piece of factory-assembled waterproofing membrane. This support system also includes several components such as the LOWER RAISERS to ensure a 10-degree tilt, the RAISER BLOCKERS to ensure that the raisers remain in place on the pedestals and the CLAMPS to fix the solar panels to the support system ^[6]. This installation method creates a connection between the panel and the cap sheet membrane without puncturing it, thus avoiding compromising the roof waterproofing. The materials and labour warranty is part of SOPREMA’s roofing system warranty programs.

Solar Thermal Wall

With an area of 1,000 ft² (⇔ 92.9 m²), the solar thermal wall features 320 panels with an air supply capacity of approximately 10,000 cfm. The selected system is the LUBI model. It is a perforated glazed air collector with a heat transfer thermal efficiency of at least 80%. On a typical day, the sun’s contact with the wall can cause the air temperature to rise as much as 45 °C above ambient temperature. The heat is redistributed inside the building, thus reducing heating demand. However, when the outside temperature is above 20 °C, as is generally the case in summer, the shutters of the solar thermal wall are closed to avoid heating the building unnecessarily.

The solar thermal wall rests on a support system on the south facade of the building. It is mainly composed of extruded aluminum finishing bars, horizontal U-bars, vertical U-bars, bottom sheet, sheet metal cladding, V-moldings, vertical spacer clips, horizontal spacer clips, and several types of flashings. 1,022 ft² (⇔ 94.9 m²) of ventilation ducts were also added.

Analysis Results

This section presents the main findings of the analysis relating to the impact of the project on energy consumption, the cost of purchasing energy, and the carbon impact of the building (including lift trucks). First, the analysis addresses the impact of the new building (2021) compared to the former building (2018). It then covers the impact of the energy efficiency project (2024) compared to the former building (2018) and compared to the new building before the installation of the system (2021).

Phase 1 – New Building (2021)

The analysis results are based on actual building data (2021), which are representative of normal building operations and are based on a full year, allowing the impact of the project to be clearly seen. Building-wide, this first phase of the project resulted in the following carbon impact improvements:

Phase 1 (2021) Compared to the Reference Year (2018)

Phase 2 – Energy Efficiency Project (2024)

The results of the analysis are based on theoretical estimates of the impact of the different systems. However, the actual consumption of the building following the commissioning of the systems for the period from March to September 2024 shows consistency between actual and theoretical performance. Extrapolating over the full year, the difference is less than 1.5%, which is reasonable for this type of project. Building-wide, this second phase of the project resulted in the following carbon impact improvements:

Phase 2 (2024) Compared to the Reference Year (2018)

Phase 2 (2024) Compared to the New Building (2021)

Impact on the Building’s Energy Consumption

Overall, both phases of the project resulted in a reduction in the building’s energy consumption (including lift trucks). Compared to the reference year (2018), Phase 1 (2021) represents 39% of energy savings (kWh), while Phase 2 (2024) accounts for 61%. In more detail, here are the main comparative results for each phase.

Phase 1 (2021) Compared to the Reference Year (2018)

Phase 1 shows a building-wide reduction in energy consumption of 52,494 kWh/year (including lift trucks) compared to the reference year (2018). This represents an approximate 16% reduction. For fossil fuels, the reduction in consumption is 49,680 kWh/year, which corresponds to a decrease of 16.3%. The consumption of renewable energy was reduced by 2,814 kWh/year, which is a decrease of 12.4%. This reduction is mainly due to the fact that the envelope of the new building (2021) is more efficient, although it is twice the size of the former building (2018), which increases the demand for heating and air conditioning.

Phase 2 (2024) Compared to the Reference Year (2018)

Phase 2 shows a building-wide reduction in energy consumption of 82,596 kWh/year (including for lift trucks) compared to the reference year (2018). This represents an approximate 25% reduction. For fossil fuels, the reduction in consumption is 145,142 kWh/year, which corresponds to a decrease of 48%. The consumption of renewable energy rose by 62,546 kWh/year, which is an increase of more than 276%. This increase is mainly due to the fact that the building consumes more electricity from renewable sources thanks to its photovoltaic solar roof.

Phase 2 (2024) Compared to the New Building (2021)

Phase 2 (2024) shows a building-wide reduction in energy consumption of 30,102 kWh/year (including for lift trucks) compared to the new building before the installation of the system (2021). This represents an approximate 9% reduction. For fossil fuels, the reduction in consumption is 145,142 kWh/year, which corresponds to a decrease of 37%. The consumption of renewable energy rose by 65,360 kWh/year, which is an increase of more than 330%. This increase is mainly due to the fact that the building consumes more electricity from renewable sources thanks to its photovoltaic solar roof.

The estimate assumes that all the electricity produced by the photovoltaic panels on the roof is used to meet the building’s needs. The rest of the electricity then comes from the external supplier. This means that approximately 84,800 kWh/year (98%) comes from SOPREMA and approximately 1,556 kWh/year (2%) from Nova Scotia Power. 

Overall, the improvements mean that the building’s energy consumption will now represent 65% (fossil) and 35% (renewable) in 2024 compared to 93% (fossil) and 7% (renewable) in 2018. In relation to the new building before the installation of the system (2021), approximately 58% of the savings are attributable to the photovoltaic solar roof, and 42% to the thermal solar wall. In the energy context of Nova Scotia, the photovoltaic solar roof appears to be the most advantageous solution for optimizing the building’s energy consumption.

Impact on the Building’s Energy Costs

Overall, both phases of the project resulted in a reduction in the building’s energy purchase cost (including for lift trucks). Compared to the reference year (2018), Phase 1 (2021) represents 28% of energy purchase savings ($), while phase 2 (2024) accounts for 72%. In more detail, here are the main comparative results of each phase.   

Phase 1 (2021) Compared to the Reference Year (2018)

Phase 1 (2021) shows a building-wide reduction in energy purchase costs of $8,937/year (including for lift trucks) compared to the reference year (2018). This represents an approximate 24.3% reduction. For fossil fuels, the cost reduction is $7,891/year, which corresponds to a decrease of 24.1%. The cost of renewable energy decreased by $1,046/year, which is a reduction of 26.2%. 

Phase 2 (2024) Compared to the Reference Year (2018)

Phase 2 (2024) shows a building-wide reduction in energy purchase costs of $22,998/year (including for lift trucks) compared to the reference year (2018). This represents an approximate 63% reduction. For fossil fuels, the cost reduction is $21,325/year, which corresponds to a decrease of 65%. The cost of renewable energy decreased by $1,673/year, which is a reduction of 42%.

Phase 2 (2024) Compared to the New Building (2021)

Phase 2 (2024) shows a building-wide reduction in energy purchase costs of $14,061/year (including for lift trucks) compared to the first year of the new building (2021). This represents an approximate 51% reduction. For fossil fuels, the cost reduction is $13,435/year, which corresponds to a decrease of 54%. The cost of renewable energy decreased by $626/year, which is a reduction of 21%. 

The estimate assumes that all the electricity produced by the rooftop photovoltaic panels is transferred to Nova Scotia Power. Depending on the monthly energy production, the electricity supplier then grants a credit at the time of billing. When rooftop electricity production is lower than building-wide demand, the shortfall is billed to SOPREMA. This results in savings of approximately $16,073/year (-97%) after maintenance costs. Regarding the solar roof, the expected cost for maintenance and replacement of defective parts is $2,185/year. This same expense item is approximately $250/year for the solar wall. It’s worth remembering that Phase 2 of the project (2024) represents a total investment of $233,319, taking into account the non-repayable grants from the various Efficiency Nova Scotia programs ($23,557). Considering all of these factors, this represents a payback period of 13.3 years. Note that 81% of the total investment value is attributable to the photovoltaic solar roof with a payback period of 15.3 years and an internal rate of return of 5.1% compared to 19% for the thermal solar wall with a payback period of 8.6 years and an internal rate of return of 10.6%. For the new building (2021), approximately 78% of the savings are attributable to the photovoltaic solar roof, therefore 22% to the thermal solar wall.  

Overall, the improvements mean that the cost of purchasing energy will now represent 83% (fossil) and 17% (renewable) in 2024 compared to 89% (fossil) and 11% (renewable) in 2018. In the energy context of Nova Scotia, photovoltaic solar roofing appears to be the most advantageous solution for generating savings on energy purchases and optimizing the return on investment.  

Impact on the Carbon Footprint of the Building

Overall, both phases of the project resulted in a reduction in the carbon impact of the building (including for lift trucks). Compared to the reference year (2018), Phase 1 (2021) represents 32% of avoided GHGs (tCO₂eq.), while Phase 2 (2024) accounts for 68%. In more detail, here are the main comparative results of each phase.

Phase 1 (2021) Compared to the Reference Year (2018)

Phase 1 (2021) shows a building-wide reduction in the carbon footprint of approximately 39 tCO₂eq./year (including for lift trucks) compared to the reference year (2018). This represents an approximate 29% reduction. For fossil fuels, the reduction of the carbon footprint is 37 tCO₂eq./year, which is a decrease of 32%. The carbon footprint of renewable energies decreased by approximately 2 tCO₂eq./year, which corresponds to a reduction of 14%.

Phase 2 (2024) Compared to the Reference Year (2018)

Phase 2 (2024) shows a building-wide reduction in the carbon footprint of approximately 85 tCO₂eq./year (including for lift trucks) compared to the reference year (2018). This represents an approximate 63.7% reduction. For fossil fuels, the reduction of the carbon footprint is 75 tCO₂eq./year, which is a decrease of 64.1%. The carbon footprint of renewable energies decreased by approximately 10 tCO₂eq./year, which corresponds to a reduction of 61%.

Phase 2 (2024) Compared to the New Building (2021)

Phase 2 (2024) shows a building-wide reduction in the carbon footprint of around 85 tCO₂eq./year (including for lift trucks) compared to the new building before the installation of the system (2021). This represents an approximate 49% reduction. For fossil fuels, the reduction of the carbon footprint is 38 tCO₂eq./year, which is a decrease of 48%. The carbon footprint of renewable energies decreased by approximately 8 tCO₂eq./year, which corresponds to a reduction of 54%.

The estimate takes into account the carbon impact of electricity supplied by Nova Scotia Power. Despite the fact that the energy production of the solar roof and the solar wall creates zero emission, a carbon footprint of 0.5 tCO₂eq. is still conservatively allocated to account for potential system maintenance work and replacement of defective parts. The solar roof allows a reduction in the carbon footprint of 74 tCO₂eq. while the solar thermal wall brings a reduction of approximately 11 tCO₂eq.

Overall, the improvements mean that the building’s energy consumption will now represent 87% (fossil) and 13% (renewable) in 2024 compared to 88% (fossil) and 12% (renewable) in 2018. For the new building (2021), approximately 87% of the avoided GHGs are attributable to the photovoltaic solar roof, therefore 13% to the thermal solar wall. In the energy context of Nova Scotia, the photovoltaic solar roof appears to be the most advantageous solution for reducing the carbon impact of the building.

Project Collaborators 

• Client: SOPREMA Canada

• Engineering firm (structure): J.M. Giffin Engineering

• Installation (solar panel mounting): Brault Roofing

• Supplier (solar panels): Natural Forces

• Supplier (solar wall): Aéronergie

Project Description

• Project: Sales Office and Warehouse – SOPREMA Dartmouth (NS)

• Location: Dartmouth (NS)

• Building surface area: 20,000 ft2 (⇔ 1,858 m2)

• Number of occupants: 12 employees

• Scope of analysis: Building operation phase

• Reference year: 2018

• Commissioning (systems): February 2024

• Units: Imperial and metric (SI)