Sustainability Cost Model Overview

Note: See the aPriori Professional User Guide for an overview of the aPriori Sustainability functionality.

Carbon Information

For all supported processes, aPriori provides carbon information data on the Part Details / Sustainability Summary tab:

Sustainability Summary tab

Supports Sustainability

Indicates whether the process includes aPriori calculations for Sustainability. This will have a value of Yes, No, or Partial. ‘Partial’ means that the routing includes a mix of supported and unsupported processes. For example, in the Machining process group not all of the operations in the routing have energy calculations (you can view the percentage of cycle time that has operation energy calculated in the Machining Formula Dependencies window). Click on the Sustainability tab for more information.

Primary Material Carbon Factor

The CO2 equivalent factor for a given mass of the selected material for the utilization process in the routing. This is specified by the material property Carbon Emissions Factor.

Energy Carbon Factor

The CO2 equivalent factor for a unit of energy consumed. This is specified by the top-level Digital Factory variable Electricity Carbon Factor. The Energy Carbon Factor is provided by aPriori partner, Ecoinvent. See Electricity Process Carbon.

Material Carbon

The amount of CO2 emissions attributable to the primary material (and any secondary material) selected for the part.

Material Carbon is the product of the Rough Mass of the part (as shown on the Part Summary tab) and the selected material’s Carbon Emissions Factor as specified in the Material Selection table, divided by the Final Yield. You can override the Carbon Emissions Factor on the Part Details / Sustainability Summary tab; this can help you to evaluate the impact of switching suppliers.

Process Carbon

The mass of CO2 equivalent that is attributed to the processes used to manufacture the part. Process Carbon is the sum of ‘Electricity Process Carbon’ and ‘Other Process Carbon’:

Electricity Process Carbon

‘Electricity Process Carbon’ is the primary source of process carbon based on an Energy Carbon Factor and energy consumption. The Energy Carbon Factor is provided by aPriori partner, Ecoinvent, and is calculated at the Digital Factory for an individual country supported by aPriori. If you have an Energy Carbon Factor that you think is more representative of your selected location, you can update the value in the Formula Dependencies or in the Digital Factory.

Note: If you want to calculate an overall Energy Carbon Factor for a mix of electricity supply technologies (for example, hydropower + offshore wind + geothermal), you can: 1) multiply the life cycle emissions of each technology (the median value is recommended) by its percentage contribution to the electricity grid to produce a factor for each separate technology, then 2) sum all of those factors to produce an overall Energy Carbon Factor. For full details, see the aPriori Professional User Guide. Note that aPriori uses figures based on Ecoinvent data for each RDL region, so there will be some variance in the calculated values when compared to Ecoinvent’s data.

Other Process Carbon

‘Other Process Carbon’ is any source of process carbon, including additional sources of carbon not related to electricity, for example, natural gas used in furnaces.

Indirect Machine Power Calculation

Note that the Indirect Machine Power calculation included in the Process Carbon calculation is the same for all processes:

Indirect Machine Power = (Facility Electricity Cost / Annual Earned Machine Hours) / Electricity Rate

  • Facility Electricity Cost: this is 0 if the Digital Factory variable Use Computed Overhead Rate is set to false, otherwise it is the product of Facility Electricity Factor and Rent Cost:

    • Facility Electricity Factor: specified by the Digital Factory variable Facility Electricity Factor.

    • Rent Cost: see formula below.

  • Annual Earned Machine Hours: the annual operating hours of the work center; see formula below.

  • Electricity Rate: specified by the Digital Factory variable Electricity Rate.

Annual Earned Machine Hours = Machine Uptime * Work Center Capacity

  • Machine Uptime: specified by the machine property Machine Uptime.

  • Work Center Capacity: this is 0 if the Digital Factory variable Use Computed Overhead Rate is set to false, otherwise it is the product of the Digital Factory variables Hours Per Shift, Shifts Per Day, and Production Days Per Year.

Rent Cost = (Work Center Footprint * (1 + Non Production Footprint Factor) * Rent Rate)

  • Work Center Footprint: the product of the machine properties Machine Length, Machine Width, and Footprint Allowance Factor.

  • Non Production Footprint Factor: specified by the Digital Factory variable Non Production Footprint Factor.

  • Rent Rate: specified by the Digital Factory variable Rent Rate.

Note: aPriori does not calculate overhead for indirect heat from natural gas.

Logistics Carbon

The mass of CO2 equivalent that is attributed to the transportation of the parts between facilities. aPriori does not calculate this by default, however users can enter their own estimates on the Part Details / Sustainability Summary tab and aPriori will include the figure in the Total Carbon calculation.

Annual Carbon

The mass of CO2 equivalent for acceptable parts produced per year. This is the product of Annual Volume and Total Carbon.

Total Carbon

The total CO2 equivalent emissions for a single part produced per year. This is the sum of Material Carbon, Process Carbon, and Logistics Carbon.

Sustainability Data in Spreadsheet Reports

aPriori provides Sustainability data in the following Spreadsheet Reports:

Part Cost Report

The Part Cost Report includes the following data in the Sustainability Outputs section for each operation in the routing:

  • Supports Sustainability (Yes, No, or Partial; if Partial, no other Sustainability data is shown.)

  • Material Carbon (kg CO2e)

  • Process Carbon (kg CO2e)

  • Logistics Carbon (kg CO2e)

  • Total Carbon (kg CO2e) This is also shown at the top of the report.

Cost Driver Report

The Cost Driver Report includes a tab called Carbon Driver Report. This contains the following graphs:

  • Total Carbon (kg CO2e): shows Material Carbon, Process Carbon, and Logistics Carbon data for each process group in the routing.

  • Process CO2 (kg CO2e): shows Process Carbon for each process in the routing, arranged in descending order from most CO2 to least.

The report also includes the following Sustainability data at the top of the report:

  • Material Carbon (kg CO2e)

  • Process Carbon (kg CO2e)

  • Logistics Carbon (kg CO2e)

  • Total Carbon (kg CO2e)

Cost Comparison Report

The Cost Comparison Report includes the following Sustainability data:

  • Supports Sustainability (Yes, No, or Partial; if Partial, no other Sustainability data is shown.)

  • Material Carbon (kg CO2e)

  • Process Carbon (kg CO2e)

  • Logistics Carbon (kg CO2e)

  • Total Carbon (kg CO2e)

Roll-Up Summary Report

The Roll-Up Summary Report includes the following Sustainability data:

  • Supports Sustainability (Yes, No, or Partial; if Partial, no other Sustainability data is shown.)

  • Total Carbon Per Part (kg CO2e)

  • Total Carbon (kg CO2e)

Note: For more information about aPriori Spreadsheet Reports, see the aPriori Professional User Guide.

Supported Processes

aPriori continues to add Sustainability calculations to more processes. Please contact your aPriori representative if there is a specific process you would like to be supported (note that aPriori does not support custom processes at this time). Currently aPriori provides Sustainability data for the following processes:

  • 2-Model Machining

    • Source Component

  • Casting - Die

    • High Pressure Die Casting

    • Melting

    • Trim

  • Heat Treatment

    • Age

    • Hot Isostatic Pressing

  • Machining

    • 2 Axis Lathe

    • 3 Axis Lathe Bar Feed Lathe with Sub Spindle

    • 3 Axis Lathe

    • 3 Axis Mill

    • 4 Axis Mill

    • 5 Axis Mill

    • Drill Press

  • Plastic Molding

    • Injection Molding

  • Sheet Metal

    • 2 Axis Router

    • 2 Roll Bending

    • 3 Roll Bending

    • 3D Laser

    • 4 Roll Bending

    • Bend Brake

    • CTL

    • Deslag

    • Fiber Laser Cut

    • Generic Press

    • Laser Cut

    • Laser Punch

    • Material Stock

    • OxyFuel Cut

    • Plasma Cut

    • Plasma Punch

    • Progressive Die

    • Shear

    • Std Press

    • Tandem Press

    • Turret Press

    • Water Jet Cut

  • Sheet Metal - Transfer Die

    • Material Stock

    • Offline Blanking

    • Transfer Die

  • Stock Machining

    • Band Saw

    • Material Stock

  • Surface Treatment

    • Anodize

    • Decorative Chrome Plating

    • Hard Chrome Plating

    • Nickel Plating

    • Power Coat Cart

    • Wet Coat Line

    • Zinc Nickel Plating

    • Zinc Plating