Canada’s Black Carbon Inventory Report 2024: chapter 2

Black Carbon Emissions and Trends in Canada

This chapter describes the main sources and sectors contributing to black carbon (BC) emissions and their trends since 2013. Emission sources have been grouped according to the following categories:

• Ore and Mineral Industries
• Oil and Gas Industry
• Electric Power Generation (Utilities)
• Manufacturing
• Transportation and Mobile Equipment
• Agriculture
• Commercial/Residential/Institutional

For each of these categories, emissions are further split into sectors.^{Footnote 1}   In keeping with international reporting requirements, Canada’s emissions of black carbon from aircraft at cruising altitude, as well as emissions from international marine navigation, are presented separately from other emission sources in this report and are excluded from Canada’s national total emissions (see Annex 3, section 3 for more information).

When observing long-term emission trends, large-scale events can have a significant impact on a portion of the time series analyzed and must be considered. The years 2020 and 2021 were marked by the COVID-19 pandemic, coinciding with observed decreases in emissions. In 2022, emissions remained relatively stable compared to 2021, but also considerably below 2019 pre-pandemic levels (-3.8 kt or -13%). Most notably, Transportation and Mobile Equipment emissions decreased by 3.8 kt or 22% between 2019 and 2022. During the same period (2019 to 2022), emissions from home firewood burning decreased by 0.56 kt (-7.6%).

Transportation and Mobile Equipment is by far the largest source of black carbon in Canada, accounting for 13 kt (51%) of total emissions in 2022. Of the various sources in this category, off-road diesel engines account for 7.7 kt (30%) of total emissions in 2022. The other large source in this category is diesel engines used for on-road transport, which account for 2.2 kt (8.4%) of total emissions.

The Commercial/Residential/Institutional category is the second-largest contributor to black carbon emissions in Canada, making up 8.1 kt or 31% of total emissions in 2022. Within this category, Home Firewood Burning is the largest source, accounting for 6.9 kt or 27% of total emissions. Wood is an abundant fuel source in Canada, and it is estimated that 6.6 million tonnes of firewood were burned in Canadian homes in 2022, a decrease of 24% since 2015 (StatCan, n.d.).

Since 2013, black carbon emissions in Canada have decreased overall by 11 kt (31%) in 2022 (Figure 2–1). Trends in black carbon emissions are largely driven by the Transportation and Mobile Equipment category and are consistent with observed trends in emissions of PM less than or equal to 2.5 microns in diameter (PM_2.5) (on which black carbon estimates are based). Details on each of the source categories and their associated sectors and emissions can be found in sections 2.1 to 2.7. An overview of the methods used to develop the black carbon inventory, improvements applied to this edition of the inventory, sources of uncertainty and future refinements are described in Chapter 3. Provincial and territorial estimates of black carbon emissions are provided in section 2.8 and Annex 4.

Notes:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Table 2–1: Black Carbon Emissions in Canada (2022)

a. The Foundries sector is being considered for omission from future inventories. If you have any questions, please contact us at apei-iepa@ec.gc.ca or 1-877-877-8375.

Other Emissions Estimated in the Black Carbon Inventory

Note:
Refer to Annex 3.3 for more information on Transportation and Mobile Equipment emissions reporting.

Figure 2–1: Trends in Canadian Black Carbon Emissions (2013 to 2022)

Note: "Other" includes the Iron Ore Pelletizing and Non-Ferrous Refining and Smelting Industry sectors.

2.1 Ore and Mineral Industries

Sources in the Ore and Mineral Industries category include primary resource extraction and processing (Table 2–2, Table 2–3 and Figure 2–2).^{Footnote 2}  For the purpose of this inventory, black carbon emissions were considered for the following industries:

• Aluminium
• Cement and Concrete
• Foundries
• Iron and Steel
• Iron Ore Pelletizing
• Mining and Rock Quarrying
• Non-Ferrous Refining and Smelting Industry

Greater sectoral coverage and further refinement of emissions from Ore and Mineral Industries are expected in future editions of the inventory.

Of all sources in the Ore and Mineral Industries category included in this inventory, the Mining and Rock Quarrying sector accounted for the largest proportion (4.5% or 1.2 kt) of total black carbon emissions in 2022 (Figure 2–2). Black carbon emissions from Mining and Rock Quarrying increased by 0.55 kt or 92% since 2013. Increases in black carbon emissions from the mining sector correspond to increased fuel use over the same time period, in addition to increases in combustion emissions reported to the National Pollutant Release Inventory (NPRI). The use of diesel to generate electricity at remote mines in northern areas, combined with the relatively high BC/PM_2.5 fraction for diesel relative to other fuels, is a significant contributor to this sector.

The second-largest source of black carbon emissions in the Ore and Mineral Industries category is the Iron and Steel Industry, which accounted for 0.12 kt or 0.48% of total black carbon emissions in 2022. Emissions from this sector have decreased by 10% since 2013. This is mainly due to a reduction in PM_2.5 emissions from one iron producing facility, which updated its estimation methodology.

The Aluminium Industry sector emitted 0.036 kt of black carbon, or 0.14% of the national total, a decrease of 0.025 kt or 41% since 2013. The decrease can be attributed to the closures of the last three Søderberg aluminium smelters between 2013 and 2015.^{Footnote 3}

Table 2-2: Black Carbon Emissions from Ore and Mineral Industries (2013 to 2022) (tonnes)

Notes:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

a. The Foundries sector is being considered for omission from future inventories. If you have any questions, please contact us at apei-iepa@ec.gc.ca or 1-877-877-8375.

Table 2–3: PM_2.5 Emissions from Combustion in Ore and Mineral Industries (2013 to 2022) (tonnes)

Figure 2–2: Trends in Canadian Black Carbon Emissions from Ore and Mineral Industries (2013 to 2022)

2.2 Oil and Gas Industry

The Oil and Gas Industry accounted for 2.6 kt or 10% of all black carbon emitted in 2022. The main sources of black carbon emissions in the Oil and Gas Industry include fuel combustion to power pumps, engines and heaters and natural gas flaring (Table 2–4, Table 2–5 and Figure 2–3). Black carbon emissions from fuel combustion are broken down by the sectors presented below. While flaring occurs in most oil and gas sectors, it is presented separately since it is a significant source of black carbon emissions.

• Disposal and Waste Treatment
• Flaring
• Heavy Crude Oil Cold Production
• Light/Medium Crude Oil Production
• Natural Gas Production and Processing
• Natural Gas Transmission and Storage
• Natural Gas Distribution
• Oil Sands In-Situ Extraction
• Oil Sands Mining, Extraction and Upgrading
• Petroleum Liquids Storage
• Petroleum Liquids Transportation
• Well Drilling/Servicing/Testing

Since 2013, black carbon emissions from the Oil and Gas industry have increased by 0.062 kt or 2.4%. Of all Oil and Gas sectors included in this inventory, Flaring accounted for the largest proportion (5% or 1.3 kt) of total black carbon emissions in 2022 (Figure 2–3). Emissions from this sector decreased by 0.11 kt or 8.1% between 2013 and 2022. Emissions from flaring are directly related to volumes of gas flared in the industry and vary from year to year due to a variety of factors. For example, federal and provincial regulations came into force in 2020 to reduce methane emissions from the oil and gas industry. Since methane is a potent greenhouse gas, flaring is preferred to venting as it reduces emissions of methane and non-methane volatile organic compounds by converting them to carbon dioxide through combustion. It does, however, increase emissions of black carbon as well as carbon monoxide, PM_2.5, and nitrogen oxides. In response to the regulations, the volume of gas flared increased between 2019 and 2022, resulting in a 10% increase in black carbon emissions from flaring over the same period.

The next two largest sources of black carbon emissions in this category are Natural Gas Production and Processing, which accounted for 0.50 kt or 2.0% of total black carbon emissions, and Oil Sands Mining, Extraction and Upgrading, which accounted for 0.40 kt or 1.5% of total black carbon emissions. Since 2013, black carbon emissions from Oil Sands Mining, Extraction and Upgrading and from Oil Sands In-Situ Extraction have increased by a combined total of 0.22 kt (65%). This is consistent with a 66% increase in crude bitumen production from mining operations and an 83% increase in crude bitumen production from in-situ thermal extraction facilities, both of which contribute to increased fuel combustion and flaring activities.

Table 2-4: Black Carbon Emissions from the Oil and Gas Industry (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Table 2–5: PM_2.5 Emissions from Combustion in the Oil and Gas Industry (2013 to 2022) (tonnes)

Figure 2–3: Trends in Canadian Black Carbon Emissions from the Oil and Gas Industry (2013 to 2022)

2.3 Electric Power Generation (Utilities)

Electric Power Generation (Utilities) sources include the combustion of coal, diesel, natural gas and other fuels for the purpose of generating electricity.

Electric Power Generation (Utilities) accounted for 0.16 kt (0.63%) of all black carbon emissions in 2022 (Table 2–6, Table 2–7 and Figure 2–4) with a 0.046 kt (22 %) decrease in emissions since 2013. Black carbon emissions from this source category are relatively low. Large facilities using solid fuels are equipped with particulate controls, while boilers and heaters using liquid and gaseous fuels emit limited particulate matter. There is relatively little diesel fuel used in large stationary electricity generation applications.

Coverage for this source category is nearly complete; the remaining sources (smaller facilities including those in remote communities that do not report their emissions to the NPRI) will be addressed in future inventories. Emissions from these sources, though low nationally, can have important regional atmospheric and air quality impacts in areas such as Canada’s North.

The largest emitter of black carbon in this category is Diesel electric power generation, which accounted for 0.11 kt (0.41%) of total black carbon emissions in 2022, and over 60% of black carbon emissions in this category. The trend is largely influenced by fluctuations in diesel-fired electricity generation. In 2022, black carbon emissions from diesel-fired electric power generation decreased by 21% from their 2013 level. Black carbon emissions decreased between 2013 and 2022 for both Coal and Natural Gas electric power generation. The 47% reduction in emissions from coal-fired electricity generation is due to the coal plant closures in Ontario and reduced coal consumption in Alberta and Saskatchewan, while the 16% reduction in emissions from natural gas-fired electricity generation is due to increased generation from renewable sources.

Table 2–6: Black Carbon Emissions from Electric Power Generation (Utilities) (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Table 2-7:  PM_2.5 Emissions from Combustion in Electric Power Generation (Utilities) (2013 to 2022) (tonnes)

Figure 2–4: Trends in Canadian Black Carbon Emissions from Electric Power Generation (Utilities) (2013 to 2022)

2.4 Manufacturing

Manufacturing sources include the Pulp and Paper Industry and Wood Products sectors (Table 2–8 and Table 2–9), which accounted for 0.34 kt or 1.3% of total black carbon emissions in 2022. While there are other manufacturing sectors, only those with significant PM_2.5 emissions from combustion are included in this inventory.

The decreasing trend in this source category between 2013 and 2022 (0.22 kt or 39%) is largely consistent with reduced production in both the Pulp and Paper Industry and Wood Products sectors.

Table 2–8: Black Carbon Emissions from Manufacturing (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Table 2-9: PM_2.5 Emissions from Combustion in Manufacturing (2013 to 2022) (tonnes)

2.5 Transportation and Mobile Equipment

Transportation and Mobile Equipment includes black carbon emissions from Air Transportation (Landing and Takeoff [LTO]), Domestic Marine Navigation, Fishing and Military, On-Road and Off-Road Transport (diesel, gasoline, liquid petroleum gas and natural gas) and Rail Transportation sectors (Table 2–10, Table 2–11and Figure 2–5). Off-Road Transport is a highly diverse sector that includes lawn and garden equipment; recreational vehicles (e.g., pleasure craft and snowmobiles); farm, construction and mining equipment; and portable generators and pumps. Both on-road and off-road diesel engines are subject to emission standards for PM and are equipped with sophisticated emission controls to reduce PM emissions. As more engines within Canada’s vehicle population are equipped with this technology PM emission rates are expected to decrease which in turn will reduce black carbon emissions.

The Transportation and Mobile Equipment category is by far the largest source of anthropogenic black carbon from combustion in Canada, accounting for 13 kt (51%) of total emissions in 2022 (Table 2–1). An important source in this category is mobile diesel engines, both on-road and off-road, which emit significant quantities of PM_2.5 and have the highest BC/PM_2.5 ratios of all black carbon sources. As a result, mobile diesel engines account for nearly all emissions from this category, and 38% of total black carbon emissions in 2022. The implementation of effective fuel and engine regulations for on-road and off-road diesel, in addition to reduced on-road diesel fuel consumption, resulted in decreases to on-road and off-road diesel emissions between 2013 and 2022 by 69% (4.8 kt) and 39% (5.0 kt) respectively, contributing to a 50% decrease overall. The remaining black carbon emissions from Transportation and Mobile Equipment come from air, marine, non-diesel on- and off-road transport, and rail transportation, which accounted for 3.3 kt and 13% of the total black carbon emitted in 2022.

Coinciding with the COVID-19 pandemic, black carbon emissions from Transportation and Mobile Equipment decreased by 2.7 kt or 16% between 2019 and 2020 and 0.33 kt or 2.3% between 2020 and 2021. Between 2021 and 2022, emissions continued to decrease by 0.73 kt or 5.3%, mostly from off-road diesel equipment. This equipment was collectively used less in 2022 relative to 2019, resulting in less diesel fuel consumed and less black carbon emitted. Between 2020 and 2022, as a result of fleet turn-over, more off-road diesel equipment were in compliance with the latest exhaust emission standards, resulting in decreased black carbon emissions despite increased diesel fuel consumption. For Air Transportation [LTO], emissions decreased by 0.08 kt or 37% between 2019 and 2020 linked with a decrease in air traffic. Emission increased by 0.02 kt or 14% between 2020 and 2021 and by 0.02 kt or 12% between 2021 and 2022.

Table 2-10: Black Carbon Emissions from Transportation and Mobile Equipment (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Other Emissions Estimated in the Black Carbon Inventory (tonnes)

Table 2-11: PM_2.5 Emissions from Combustion in Transportation and Mobile Equipment (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Other Emissions Estimated in the Black Carbon Inventory (tonnes)

Figure 2–5: Trends in Canadian Black Carbon Emissions from Transportation and Mobile Equipment (2013 to 2022)

2.6 Agriculture

Agriculture sources consist of Agricultural Fuel Use for non-mobile equipment (e.g., for drying grain, heating barns) and accounted for 0.025 kt (0.10%) of total black carbon emitted in 2022 (Table 2–12 and Table 2–13). Since 2013, emissions of black carbon from this source decreased by 0.021 kt or 45% in 2022. Throughout the time series, Alberta contributed decreasing amounts of the total Canadian black carbon emissions for this sector; contributing 73% in 2013 and 58% in 2022. On the other hand, Ontario contributed 18% of the total Canadian black carbon emissions for this sector in 2013 and 27% in 2022. The decrease in black carbon emissions between 2013 and 2022 is largely a result of reduced coal consumption in non-mobile equipment in Alberta.

Table 2-12: Black Carbon Emissions from Agriculture (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Table 2-13: PM_2.5 Emissions from Combustion in Agriculture (2013 to 2022) (tonnes)

2.7 Commercial/Residential/Institutional Sources

Commercial/Residential/Institutional sources include Home Firewood Burning, Commercial and Institutional Fuel Combustion, Construction Fuel Combustion and Residential Fuel Combustion. The majority of emissions from these sources are due to combustion in large, relatively efficient commercial boilers, or in small, less-efficient residential fireplaces and wood stoves.

Of all Commercial/Residential/Institutional sources, Home Firewood Burning accounted for the largest proportion (6.9 kt or 27%) of total black carbon emissions in 2022 (Table 2–14 and Table 2–15). Emissions from Home Firewood Burning are split into the following subsectors:

• Fireplaces
• Furnaces
• Wood Stoves

A key determinant of total emissions from Home Firewood Burning is the quantity of wood burned in each type of device (residential wood stoves, furnaces and fireplaces). The decreasing trend in this sector between 2013 and 2022 (1.2 kt or 14%) can be attributed in part to the reduction in the use of conventional fireplaces and wood stoves and their replacement with fireplace inserts, furnaces and stoves with improved emission controls and combustion efficiencies. Between 2019 and 2022, emissions from this source decreased by 0.56 kt or 7.6% due to warmer heating seasons, as indicated by an 4% decrease in heating degree-days.

Excluding Home Firewood Burning, the remainder of this category accounted for 1.2 kt (4.7%) of total black carbon emissions in 2022. Commercial and Institutional Fuel Combustion accounted for 1.0 kt (3.9%) of total emissions, making it the second largest source of black carbon emissions in this category.

Table 2-14: Black Carbon Emissions from Commercial/Residential/Institutional Sources (2013 to 2022) (tonnes)

Note:
Totals may not add up due to rounding.
Values in this report have been rounded to two significant digits.

Table 2-15: PM_2.5 Emissions from Combustion of Commercial/Residential/Institutional Sources (2013 to 2022) (tonnes)

2.8 Provincial and Territorial Black Carbon Emissions Trends

This section describes black carbon emissions trends by Canadian provinces and territories for 2013 to 2022. Complete provincial and territorial estimates are provided in Annex 4.

Since 2013, black carbon emission trends in Canadian provinces and territories are mostly consistent with the national trend (Figure 2–1 and Figure 2–6), with decreasing emissions. According to Table 2–16, the most significant decrease in total emissions between 2013 and 2022 occurred in Alberta (5.5 kt or 28%) followed by Quebec (5.1 kt or 34%) and Ontario (5.0 kt or 30%). By percentage, the decrease is most notable for New Brunswick (66%).

Table 2–16: Black Carbon Emissions from Canadian Provinces and Territories (2013 to 2022) (tonnes)

Figure 2–6: Trends in Black Carbon Emissions from Canadian Provinces and Territories

The full-time series of national, provincial, and territorial black carbon emissions from 2013 to 2022 are also available online on the Government of Canada Open Data Portal.

References, Chapter 2, Black Carbon Emissions and Trends in Canada

[StatCan] Statistics Canada. No date. Households and the Environment Survey. [accessed 2024 Jan].