Vehicles Editor¶

Overview¶

The Vehicle Editor in PyGREET is a LCA tool for defining, customizing, and analyzing vehicle-specific data. It supports the modeling of energy use and emissions over a vehicle's full lifecycle—from manufacturing to operation and end-of-life. Vehicles can either be standard, or non-standard vehicles. Non-standard vehicles contain one or more materials or fuels that have a source type of "Output of a Previous Process." These vehicles cannot have results generated within the vehicle editor, and instead must be added as blocks to a pathway in the Pathway Editor

The vehicle editor consists of three bottom tabs:

General Information
Results
Usage Tab

The functionality of the usage tab is explained within the relevant section within the Tab Navigation Section.

Info

Usage tab are only important for those vehicles used as part of pathways.

General Information¶

The general information section consists of four sections, along with the name, notes, and vehicle type.

Vehicle Type¶

The vehicle type is chosen as a dropdown.

Vehicle Details Section¶

Several parameters to describe the vehicle:

Lifetime VMT
Payload and passengers
Electric range
Urban share

Lifetime VMT

The Lifetime VMT (vehicle miles traveled) is specific to the use of vehicle construction components. If we account for components, we must then know how many times they are going to be used or replaced over the lifetime of the vehicle in order to account for upstream energy and emissions associated with them.

Payload

The Payload is optional, if a payload is defined, then the results can be normalized using that payload and displayed in X/(ton mi) where X represents either an energy or a mass.

Passengers

The number of passenger is also used in the same manner, if passengers are defined then results can be expressed per passenger mile.

Electric Range

It is the total distance a vehicle can travel using only the energy stored in its onboard battery pack, without the assistance of an internal combustion engine. This parameter is used to automatically calculate VMT Share

Urban Share

The Urban Share for a vehicle defines the percentage of total VMT that occurs within densely populated urban areas. This parameter is used to geographically allocate tailpipe and non-exhaust emissions, which is essential for assessing the local impacts of criteria air pollutants.

Vehicle Cycle Modeling Section¶

This section allows users to add various materials related to the construction of the vehicle.

Major Groups¶

Materials are broken down into five groups:

ADR (Assembly, Disassembly, and Recycling)
Battery
Components
Fluids
Others

Each section can be expanded or hidden by clicking on the carat on the major group row.

Adding Materials¶

Click the + icon next to the group title
Search for and click on the desired resource flow
For each material declare unitary quantity, number of units, replacement, source specification

Figure 2: The Vehicle Cycle Modeling Section with some data filled in

Unitary Quantity

The mass of a single item of this component.

# of Units

The number of units or number of unitary quantities on this vehicle.

Replacements

The number of replacement for the all units on this vehicle over it’s lifetime.

Source

For each of these vehicle construction items, a pathways is associated so that the algorithms can use the upstream for the production of these components in the WTW results.

Warning

The Lifetime VMT of the vehicle must be defined if any materials are added to the vehicle.

"Output of a Previous Process

If a material source has a source type of "Output of a previous process," the vehicle is considered non-standard. The vehicle using this material must be modeled in the Pathway Editor to connect upstream pathways and generate results.

Non-Combustion Emissions Table¶

The non-combustion emissions (or non-exhaust emissions) are not related to the internal combustion engine operation, but to external factors, such as tire and brake use or gasoline evaporation.

This table functions similarly to the table located in a stationary process. Serves to represent all emissions produced during the operation of a vehicle. For more information, see the Non-Combustion Emissions table located in the Stationary Process Editor

Figure 3: The Non-Combustion Emissions Table for Vehicles

Note

Emissions are expressed per unit of distance traveled.

Operational Modes Table¶

The Operational Modes Table allows users to add one or more operational modes to a vehicle. Operational modes represent the fuel used and emissions generated by vehicle operation, and can be created or edited in The Operational Mode Editor. The Operational Modes table consists of three columns: The name of the Operational Mode, the type of the Mode, and the VMT Share. Operational Modes can be added by clicking the + icon that appears when hovering over the Operational Modes section header.

The name of a operational mode may be clicked on to open The Operational Mode Editor to edit the respective mode.

Warning

The VMT Share of all operational modes must total to 100%.

For vehicles that contain one or more operational modes that use electricity, the user may click the green > icon to calculate the VMT share automatically.

Figure 4: The Operational Modes Table for Vehicles

Results¶

Important

Results can only be generated in the Vehicle Editor for standard vehicles (i.e vehicles with no material or fuel that have a source type of "Output of Previous Process.") Non-standard vehicles must instead be modeled in the Pathway Editor. However, results for non-standard vehicles within the Pathway Editor have the same format as results for standard vehicles, described below.

Vehicle results are calculated and then broken down into individual sections in a large table.

Each row in the table represents one type of emission. The Vehicle Results table splits rows across multiple pages to improve performance. The amount of rows per page, and what page is visible, can be controlled in the bottom right of the editor.

Results View Controls¶

Metric: The rows of the results table can be filtered to a desired metric / resource.
Metric value slider: Filter the table based on a minimum value for C2G metrics, e.g., showing metrics >= 1e-5
Energy Unit, Emission Unit, and Functional unit: Can be set at the top of the results view
Simulation year: Displayed
Technology year: Displayed with an information circle explaining the technology lag year
Copy Table: Copies the table to the clipboard for pasting into Microsoft Excel or similar programs

Figure 6: The explanation of the technology lag year

Results Columns¶

Results are broken down into the following columns:

WTP (Well-to-Pump) - highlighted
Columns for each energy source in each operational mode
Non-Exhaust Emissions
Total Vehicle Operation
WTW (Well-to-Wheel) - highlighted
One column for each material group:
- Components
- ADR
- Fluids
- Battery
- Others
C2G (Cradle-to-Grave) - highlighted