2.2.1 Six Steps to Completing the Template
2.1 ISSUES TO BE RESOLVED PRIOR TO COMPILING THE INVENTORY
2.1.1 Boundaries
2.1.2 Data Sources
2.1.3 Level of Data Disaggregation
2.1.4 Future Uses of GHG Emissions Data
2.1.5 Uncertainty in GHG Emission Estimates
2.2 INVENTORY TEMPLATE
2.2.1 Six Steps to Completing the Template
The recommended approach for completing the worksheet and inventory includes six steps:
These steps are described in more detail below:
Step 1: Record all fuel consumption and electrical energy consumption in standard units.
The first step is to record the volume/mass of all fuel sources used on site. These values should be entered into the blue column entitled “Volume/Mass Consumed.” Include:
• all energy consumed directly for stationary combustion (e.g. coal, oil, natural gas, coke, biomass, et cetera); and
• all fuel consumed by mobile sources owned or leased by the company for transportation and heavy equipment on site (e.g. diesel fuel, gasoline, jet fuel).
When using the worksheet, be sure to select the appropriate units for the
data you are entering by selecting either m3 or litres from the pull down menus
provided. You must select the units for each type of fuel you consume with the
exception of natural gas (which must be reported in m3) and solid fuels (which
must be reported in tonnes).
For worksheet users, the worksheet will automatically calculate the corresponding
energy value in GJ by applying the heating value for that fuel. Energy Content
values expressed in gross or higher heating values (HHV) for most fuel types
have been included in Part 7 for those completing the conversion manually.
Due to differences in combustion processes - which directly affect GHG emissions - it is important to distinguish between different uses of the same fuel. Where precise measurements are available (for example, if different fuel storage tanks are used for different uses), enter these data alongside the appropriate use categories. Where measurements are not available, consult with appropriate parties on-site to estimate the percentage of each type of fuel used for different uses, and enter these estimates into the worksheet. While this might be easily estimated for some fuels and uses, others may prove more problematic. For example, it may be difficult to differentiate between car and light truck fuel use on site. In this case, if you know how much gasoline is used collectively by the two categories, you may choose to allocate fuel use between the two based on the proportionate number of kilometers driven by each category. Document all assumptions so that consistent methodologies can be applied in future years and, as methodologies are refined over time, differences in emissions that are associated with methodological changes can be identified. Be sure to account for the entire volume/mass consumed of each fuel.
Next, record electrical energy consumed (in kWh) in the row corresponding to the jurisdiction where it was purchased. The template will automatically make the conversion from kWh to GJ. For those companies purchasing energy from sources other than the grid, enter the electrical energy consumed in the row marked “Other” and specify the source of the electricity.
Finally, record any other energy consumed that has been generated off-site - such as steam - and any energy that is sold or transferred for use off site (in GJ). Also record any self-generated electricity derived from non-fossil fuel sources. This section does not include self-generated electricity derived from fossil fuels. The fuels used to generate electricity on site should be reported with energy consumed directly for stationary combustion.
Based on these entries, the worksheet will calculate Total Energy Use.
Step 2: Calculate GHG Emissions Associated with Fuel and Electrical
Energy Consumption
Based on the data entered for total energy consumed (including fossil and other fuels, electrical energy, and thermal energy), the worksheet will automatically calculate GHG emissions by applying standard emission factors and the appropriate Global Warming Potential (GWP) values. These emissions will be presented both by individual GHG gas and by tonnes of CO2 equivalent (CO2e). The emissions are presented in the orange columns entitled Direct Emissions: Standard Emissions Factors (default values).
For those completing the inventory manually, for each energy source, the appropriate emission factors supplied in Part 7 must be multiplied by the quantity of fuel consumed and converted to standard units. To calculate CO2e, the GWPs provided in Part 7 must be applied as follows:
Tonnes CO2e = (tonnes CO2*1) + (tonnes CH4*21) + (tonnes N2O*310)
Where 1, 21, and 310 are the GWPs for CO2, CH4 and N2O respectively.
There are several cases where you may choose to override the default emissions factors to provide more specific emissions data. In these situations, enter the specific emissions data in the appropriate blue columns in the section entitled Direct Emissions: Process-specific Emissions Factors (enter to override default factors). Several situations when you may choose to use this function are described below:
a) If you have equipment or process specific emissions data for a particular piece of equipment or combustion process, you should enter the more specific data.
b) For electrical energy consumption, the Canadian Electricity Association publishes indirect emission factors (expressed in CO2e) by province. At the time of publication, the most recent factors available were for 1997, and these are included in Part 7. MAC will provide its member companies with annual updates of emissions factors. While these provincial factors are the default values used to calculate indirect GHG emissions within the worksheet, MAC encourages you to contact your supplier to obtain more precise emissions data associated with the generation of electrical energy you purchase. Many suppliers will be able to provide you with more up-to-date information on emissions factors, and will be able to present emission factors by gas type (not just by CO2e).c) If energy is purchased from a source other than the grid (either electrical or steam), emission factors should be solicited from the energy provider and manually entered into the worksheet. These emissions will be added to determine the Indirect Emissions Total.
If energy is sold back into the grid or to another party (either electrical or steam), enter the total energy in kWh. This value will be subtracted from the total energy values reported to calculate Total Energy Use, and used to calculate GHG emissions per tonne of production.
Step 3: Record emissions from other sources
The last sources of emissions to be entered into the worksheet are controlled and uncontrolled process emissions. The worksheet lists some examples, including:• Fugitive Emissions (e.g. methane from oil sands);
• Emissions associated with calcination and use of carbonate reagents;
• Fugitive emissions of HCFCs from refrigeration & cooling equipment;
• Emissions from use of explosives;
• Emissions associated with pyrometallurgy; and
• Emissions of SF6 from magnesium processing.
The magnitude and significance of these emissions will vary from facility to facility, depending on equipment, processes used and management practices. For example, some companies have found some of these sources (e.g. use of carbonate reagents or operational leaks from refrigeration equipment) to be insignificant relative to emissions related to energy consumption. In other cases (e.g. use of SF6 in magnesium production), these process-related emissions are very significant emission sources.
It is likely that more information regarding fugitive emissions and process
sources will become available over time. One such example, methane from oil
sands operations (including fugitive emissions from the open mine face and methanogenic
bacteria in tailings ponds), is currently being studied.
The worksheet does not automatically calculate emissions for these sources since
they tend to be process-specific. For each applicable “other source”
of emissions, enter the quantity of emissions and specify the associated units.
Default emissions factors are not provided within the spreadsheet (except for
ANFO explosives), so you are required to calculate the associated GHG emissions
and enter the emissions data within the fields. Further guidance for completing
these cells is as follows:
• For emissions related to reagent use, worksheet users are to consult the molecular formula for the specific reaction, determine the proportion of CO2 released and calculate the amount of CO2 emitted based on the amount of reagent used.
• For emissions associated with limestone use in the metallurgical smelting process, calculate emissions by obtaining data on the consumption of raw limestone and applying the non-dolomitic lime production emission factor (440 g CO2/kg feed).
• For controlled or uncontrolled releases of other GHGs (such as SF6 or HCFCs), enter the amount released in the appropriate cell and then multiply this number by the corresponding GWP (as found in Part 7) to determine CO2e.
• For emissions related to use of explosives, enter the mass of explosives used (in tonnes). The worksheet will automatically calculate the associated CO2 emissions for ANFO, using an emission factor of 0.189 tonnes of CO2 per tonne of explosive. If you are using another type of explosive, manually enter the associated emissions factors.
• For emissions related to pyrometallurgy (such as the use of metallurgical coke as a reducing agent), worksheet users are to consult the molecular formula for the specific reaction, determine the proportion of CO2 and other greenhouse gases released, and calculate the amount of CO2 and other greenhouse gases emitted based on the amount of agent used.
SF6 emissions should be based on actual consumption records.
Potential sources for HFC and HCFC inventory information include release reports,
purchasing information, and equipment log books, where technicians record the
amount of material added to systems that require replenishing. Where actual
release data are not available, Environment Canada’s 1997 Greenhouse Gas
Inventory Report suggests emission factors for HFCs in a number of common applications:
Once you enter the emissions of each applicable greenhouse gas, the worksheet
will automatically apply the appropriate Global Warming Potentials and add these
“Other” emissions to the Direct Emissions Total.
The worksheet automatically sums Direct and Indirect Emissions, expressed in
CO2e, to arrive at Absolute CO2e.
Step 4: Record production data.
The next step is to enter production data, which will be used to link emissions
data to performance. The appropriate measure(s) of production depends on the
type of operation and the ability of the operation to attribute emissions to
specific production processes. It is essential that the production data entered
here be appropriate to the GHG emissions reported in this worksheet.
Examples included in the worksheet include:
• Tonnes of mill throughput;
• Tonnes of ore product;
• Tonnes of refined metal;
• Tonnes of contained metal; and
• Troy ounces of gold or silver.
Enter production data in the measure(s) most commonly used within your operation,
provided they are reflective of the reported GHG emissions.
Step 5: Calculate Performance Indicators
The worksheet will automatically calculate performance indicators for each measure of production entered in Step 4, including:
• CO2e/tonne of ore product;
• CO2e/tonne of throughput;
• CO2e/tonne of refined metal;
• CO2e/tonne of contained metal;
• CO2e/troy ounce of gold/silver; and
• Energy intensity of production (Total Energy Consumed/appropriate production measure expressed in GJ/tonne).
Step 6: Analyse GHG emissions inventory to identify and account for significant
changes.
It is important to analyse the emissions data contained in your annual GHG
emissions inventory to identify significant changes in emissions and determine
their root cause. This analysis allows you to determine how successful your
emissions reduction efforts have been, and provides important information that
should be reflected within your GHG emissions reduction action plan.
When completing this analysis, be sure to consider the direction and magnitude
of:
• Trends in absolute emissions over time;
• Trends in emissions per unit of production;
• Trends in direct emissions; and
• Trends in indirect emissions.
Once you’ve identified these trends, determine the factors that most directly contributed to them. Consider the following elements:
• Changes in the boundaries of your inventory (for example, have the boundaries been impacted by sales, acquisitions, or shutdowns? Have you expanded the boundaries to include additional emissions, such as those associated with transportation contractors?);
• Changes in production rates;
• Changes in the production processes (for example, have new processes been added, or have systems or processes been significantly modified or shutdown? Have inputs or outputs been substantially changed? Has depth of mines changed?);
• Impact of specific initiatives you have undertaken to reduce direct and/or indirect emissions (see Part 5 for guidance on estimating emissions changes from specific projects); and
• Factors beyond your direct control that affect the indirect GHG emissions associated with your operations.
This analysis should be documented, and should inform the creation or modification
of your GHG emissions reduction action plan.
