Components represent physical activities whose CO₂e flux needs to be accounted for. They are created from component blueprints that contain sets of equations used to calculate a transfer of CO₂e into or out of the atmosphere. To accurately model quantification of CO₂e Removal the correct components, and component blueprints used to create them, must be identified. This tutorial covers examples of how to model an LCA using components.

Subdivide by type

CO₂e Removal is calculated as the following in all Isometric Protocols,

CO2eRemoval,RP=CO2eStored,RPCO2eCounterfactual,RPCO2eEmissions,RP {CO₂e}_{Removal, RP} = {CO₂e}_{Stored, RP} - {CO₂e}_{Counterfactual, RP} - {CO₂e}_{Emissions, RP}

It is useful to separate calculations for each parameter in this equation and identify the components necessary to model each group. In Certify components have a Type which denotes whether they are used to calculate CO2eStored,RP{CO₂e}_{Stored, RP}, CO2eCounterfactual,RP{CO₂e}_{Counterfactual, RP} or CO2eEmissions,RP{CO₂e}_{Emissions, RP}. Types denote a carbon accounting category and flux direction, either CO₂e sequestered or emitted. The types used to calculate each parameter within CO2eRemoval,RP{CO₂e}_{Removal, RP} are as follows:

Component TypeApplicable toDescription of Component TypeCO₂e Flux Direction
sequestrationCO2eStored,RP{CO₂e}_{Stored, RP}Calculations of CO₂e sequestered through storage or natural processesSequestered
lossCO2eStored,RP{CO₂e}_{Stored, RP}CO₂e losses and leakage before reaching permanent storageEmitted
counterfactualCO2eCounterfactual,RP{CO₂e}_{Counterfactual, RP}Baseline calculations to compare actual sequestration against alternative scenariosEmitted
activityCO2eEmissions,RP{CO₂e}_{Emissions, RP}Fuel and energy usage, manufacturing processes and embodied emissionsEmitted
reductionCO2eEmissions,RP{CO₂e}_{Emissions, RP}Activity emissions that have been reduced by other claims or offsetsSequestered

This tutorial will focus on how to identify components for CO2eEmissions,RP{CO₂e}_{Emissions, RP}.

Identifying components within types

CO2eEmissions,RP{CO₂e}_{Emissions, RP} can be calculated by measuring CO₂e emissions directly, for example with a flow meter and gas analyzer, or by collecting activity data and using the following general equation:

Activity GHG emissions=activity × emission factor Activity\ GHG\ emissions = activity\ \times\ emission\ factor

Where

  • Activity GHG emissionsActivity\ GHG \ emissions is the emissions associated with an activity, presented in tonnes CO₂e;
  • activityactivity is the activity that took place, presented in no. units. Activity data can be measured, modeled, or calculated; and
  • emission factoremission\ factor is the conversion factor for the activity, presented in tonnes CO₂e / unit

Typically a single component is used to represent each instance of the above equation where activity data is multiplied by an emission factor. For example, a single transportation journey may be represented by one component created from the component blueprint Transport emissions. Each component blueprint has a set of necessary inputs to calculate the component’s CO₂e flux; in this case the component blueprint defines inputs for datapoints representing a distance, mass and emission factor. For this component the mass transported, distance travelled, and emission factor specific to the vehicle used for that particular journey would be inputs to the component.

Once you have identified a component by finding a single emission source, typically an instance of multiplying activity data by an emission factor, you must select which component blueprint to create it from. Identifying components and the component blueprints used to create them is typically an iterative process, as the blueprint - the equations used to calculate the transfer of CO₂e into or out of the atmosphere - is fundamental to the component itself. Certify offers an extensive library of component blueprints that can be used to model CO2eEmissions,RP{CO₂e}_{Emissions, RP} across a variety of pathways.

To find the correct component blueprint it is useful to narrow down the existing library by how the emission was generated - energy use, transportation, embodied emissions or direct emissions. These types of emissions relate to Isometric’s LCA Modules: Energy Use Accounting, Transportation Emissions Accounting, Embodied Emissions Accounting. This tutorial documents examples of the component blueprints that are frequently applicable to each type of emission. As the Certify library of component blueprints is always growing, please check our full component blueprint library if none of the examples are suitable. If a component blueprint does not exist to meet your needs please contact support@isometric.com.

Energy Use Accounting

Energy use accounting (see Module) typically requires calculating the emissions related to electricity, a solid fuel, a liquid fuel, or a gaseous fuel.

Electricity

The following components can be used to model electricity emissions in Certify:

Component BlueprintUse caseCalculations
Energy-based CI emissionsThe most generic energy use blueprintresult=energy×carbon_intensity\text{result} = energy \times carbon\_intensity
Grid electricity use emissionsFor electricity emissions where the absolute amount of electricity consumed is knownresult=electricity_use×grid_carbon_intensity\text{result} = electricity\_use \times grid\_carbon\_intensity
Metered electricity use emissionsFor electricity emissions where the meter reading is knownresult=(final_readoutinitial_readout)×carbon_intensity\text{result} = (final\_readout - initial\_readout) \times carbon\_intensity
Time-based grid electricity use emissionsFor electricity emissions where the time drawn from the grid is knownresult=time×average_power×grid_carbon_intensity\text{result} = time \times average\_power \times grid\_carbon\_intensity
Electricity-ratio based emissionsFor electricity emissions where electricity consumption is extrapolated from an efficiency value, such as the amount of electricity consumed per tonne of material processedresult=mass_feedstock×energy×carbon_intensity\text{result} = mass\_feedstock \times energy \times carbon\_intensity
Electricity use emissions with low-carbon procurementFor electricity emissions where low-carbon is procuredPlease see blueprint for full equation

It is always preferable to use the most specific component blueprint available.

Example 1

Imagine the initial meter readout and final meter readout is collected every month by a facility in a project. A grid emission factor specific to the geography has been sourced. Data for this month is as follows:

Datapoint #DatapointValueUnit
Ainitial meter readout20kWh
Bfinal meter readout50kWh
Celectricity emission factor1.2kgCO₂e/kWh

The component blueprints Energy-based CI emissions, Grid electricity use emissions and Metered electricity use emissions could all be used to calculate the correct CO₂e flux for this emission.

For example, the component blueprint Grid electricity use emissions requires inputs for electricity_use and grid_carbon_intensity. (B)-(A) could be used to obtain an input for electricity_use and (C) as an input for grid_carbon_intensity. However, as the component blueprint Metered electricity use emissions has inputs for the final readout and initial readout it is more accurate and transparent to represent this data using that component blueprint, so it should be chosen. If the final readout and initial readout were not available then using Grid electricity use emissions would be suitable.

If multiple month’s data is being submitted a component should be created for each month of electricity consumption.

Example 2

A project developer attempted to source primary data for a piece of equipment’s electricity consumption, but it was not available. Instead, the project developer sourced an emission factor specific to the technology of the equipment which documents how much electricity is consumed per tonne of material processed. The developer does have primary measurements of how much material was processed on site, this was measured using a calibrated scale.

Datapoint #DatapointValueUnit
Amass of feedstock processed10tonnes
Befficiency of equipment2kWh/tonnes
Celectricity emission factor1.2kgCO₂e/kWh

In this example the component blueprint Electricity-ratio based emissions would be suitable to model the emission.

Fuel

When choosing a component blueprint to create a component for a fuel emission, it is useful to understand what type of fuel has been used and whether it has been measured as a mass or a volume.

For mass based calculations:

Component BlueprintUse caseCalculations
Mass-based CI emissionsFor emissions where the mass of material consumed is known, genericresult=mass×carbon_intensity\text{result} = mass \times carbon\_intensity
Fuel usage by mass emissionsFor emissions where the mass of material consumed is known, specific to fuelresult=mass_of_fuel×fuel_combustion_carbon_intensity\text{result} = mass\_of\_fuel \times fuel\_combustion\_carbon\_intensity
Mass-ratio based CI emissionsFor emissions where the mass of material used is extrapolated from an efficiency value, such as the mass of material consumed per tonne of feedstock processedresult=mass_ratio×carbon_intensity\text{result} = mass\_ratio \times carbon\_intensity
Fuel usage by mass emissions, accounting for BCU claimsFor emissions where the mass of fuel consumed is known and Book and Claim Units are usedSee blueprint for full equation

For volume based calculations:

Component BlueprintUse caseCalculations
Volume-based CI emissionsFor emissions where the volume consumed is known, generic to any liquid or gasresult=volume×carbon_intensity\text{result} = volume \times carbon\_intensity
Fuel usage by volume emissionsFor emissions where the volume consumed is known, specific to fuelsresult=volume_of_fuel×fuel_combustion_carbon_intensity\text{result} = volume\_of\_fuel \times fuel\_combustion\_carbon\_intensity
Volume per feedstock-unit mass based emissionsFor emissions where the volume of material used is extrapolated from an efficiency value, such as the volume of material consumed per tonne of feedstock processedresult=volume_material_per_mass×emissions_factor×feedstock_mass\text{result} = volume\_material\_per\_mass \times emissions\_factor \times feedstock\_mass
Fuel usage by volume emissions, accounting for BCU claimsFor emissions where the volume of fuel consumed is known and Book and Claim Units are usedSee blueprint for full equation

Transportation Emissions Accounting

Transportation emissions accounting (see Module) can be calculated with any of the component blueprints applicable to fuel or the following component blueprints specific to transportation:

Component BlueprintUse caseCalculations
Transport emissionsFor transportation where the mass and distance travelled is knownresult=mass×distance×carbon_intensity\text{result} = mass \times distance \times carbon\_intensity
Mass-distance-based CI emissionsUsed when the mass and distance travelled have been aggregated for multiple small tripsresult=mass_distance×carbon_intensity\text{result} = mass\_distance \times carbon\_intensity
Distance-based emissionsFor transportation where only the distance travelled is known, acceptable for transportation by passenger car or airplaneresult=distance×carbon_intensity\text{result} = distance \times carbon\_intensity
Fuel consumption based transport emissionsFor transportation where the fuel consumed is extrapolated based on vehicle efficiencyresult=distance×fuel_carbon_intensityfuel_economy\text{result} = \frac{distance \times fuel\_carbon\_intensity}{fuel\_economy}

Embodied Emissions Accounting

Embodied emissions accounting (see Module) can be calculated with the following component blueprints.

For mass based calculations (typically applicable to materials and consumables):

Component BlueprintUse caseCalculations
Mass-based CI emissionsFor emissions where the mass of material consumed is known, genericresult=mass×carbon_intensity\text{result} = mass \times carbon\_intensity
Mass-ratio based CI emissionsFor emissions where the mass of material used is extrapolated from an efficiency value, such as the mass of material consumed per tonne of feedstock processedresult=mass_ratio×carbon_intensity\text{result} = mass\_ratio \times carbon\_intensity

For volume based calculations (typically applicable to consumables):

Component BlueprintUse caseCalculations
Volume-based CI emissionsFor emissions where the volume consumed is known, generic to any liquid or gasresult=volume×carbon_intensity\text{result} = volume \times carbon\_intensity
Volume per feedstock-unit mass based emissionsFor emissions where the volume of material used is extrapolated from an efficiency value, such as the volume of material consumed per tonne of feedstock processedresult=volume_material_per_mass×emissions_factor×feedstock_mass\text{result} = volume\_material\_per\_mass \times emissions\_factor \times feedstock\_mass

Otherwise (typically applicable to materials, consumables and services):

Component BlueprintUse caseCalculations
Currency-based CI emissionsWhere emissions are calculated from the cost of a material, equipment or serviceresult=amount_spent×carbon_intensity\text{result} = amount\_spent \times carbon\_intensity
Embodied emissionsWhen emissions is reported as a single figure, for example in the case they are sourced from an EPDresult=embodied_emissions\text{result} = embodied\_emissions

Example 3

A project developer has built a new facility for their project and they have a bill of materials which states what materials were used to construct the facility. This includes the masses of steel, concrete and aluminium. An emission factor is sourced for each material. Three separate components are created from the component blueprint Mass-based CI emissions to model these embodied emissions. For each component the mass of material and emission factor of the material is supplied as a component input.

Example 4

A project developer has purchased a new piece of equipment for their project and attempted to source an environmental product declaration (EPD), independently verified life cycle assessment, or specific emission factor for the equipment but was unsuccessful. Instead, the project developer sourced an emission factor based on the total cost of equipment and specific to the type of equipment purchased. To model this emission a component is created from the blueprint Currency-based CI emissions, and the price paid for the equipment and emission factor sourced are supplied as component inputs.

Direct Emissions Accounting

Where emissions are directly measured, typically in the case of flue gases or gas leakage:

Component BlueprintUse caseCalculations
GHG direct emissionsDirect emissions from a processresult=mass_flow×concentration×global_warming_potential\text{result} = mass\_flow \times concentration \times global\_warming\_potential
GHG leakage emissionsDirect emissions from a process based on gas energy usedresult=gas_energy_used×global_warming_potential×leakage_fractiongas_energy_density\text{result} = \frac{gas\_energy\_used \times global\_warming\_potential \times leakage\_fraction}{gas\_energy\_density}

Granularity

The number and type of components used to represent the calculation of CO2eEmissions,RP{CO₂e}_{Emissions, RP} will differ by project depending on data collection procedures. This is because the frequency and nature of data collected impacts how CO2eEmissions,RP{CO₂e}_{Emissions, RP} is calculated. For example, if multiple transportation journeys occurred as part of the project these could be represented with multiple components to ensure accuracy in data representation.

Whilst it is almost always preferable to represent calculations to their fullest granularity using multiple components, e.g. for each transportation trip, there are some exceptions to this:

  1. Where data is already collected and measured with sufficient accuracy it is not necessary to subdivide it further. For example, it is equally valid to measure the electricity consumption of all equipment in a facility individually, and to represent each calculation as a separate component, as it is to measure the entire facility’s electricity consumption and represent this in a single component as long as all emission sources within the project’s system boundaries are accounted for.
  2. In some cases it may be prudent to use a single component to model a large number of like-for-like activities. For example if hundreds of transportation trips were made by the same type of vehicle in the same reporting period, the total distance travelled and mass transported could be summed respectively and used as inputs to a Mass-distance-based CI emissions component. In this case individual measurements for each trip should be provided as a source to evidence the total values.