Co-Products
Co-Products are resources which are secondary products created alongside the main output which can be accounted for in the production of that resource. CoProducts can be added to a stationary process from the stationary process editor either by selecting a resource which is not in an input group and right clicking the "Set As Co-Product" option or by clicking the Add/Edit Co-Products button.
Allocation and Displacement methods
The GREET model has multiple ways of handling the co-products. The two different approaches are Allocation and Displacement methods. In GREET.net both of those methods can be used at the Process level.
For more details, please visit the Co-Prodcuts calculations page
Adding Co-Products
To add a Co-Product to an existing stationary process go to the data editor and select "Modify Existing Process" or "Add Stationary Process" to add a new process with co-products. In the stationary process editor click on the Add/Edit Co-Products and a new window will open for modifying the co-products. To add a new co-product click on the "+ Add" tab at the top of the window. A new co-product tab will be created and the parameters for the new Co-Product will be displayed. The co-product will not be added until the Save or "Save and Close" button is clicked.
Editing Existing Co-Products
To edit a Co-Product that has already been added to a process click the Add/Edit Co-Products button and select the tab at the top of the window which contains the desired co-product resource. From there the parameters and method to use for calculating co-product credits can be selected.
If the allocation treatment method is selected, the allocation type can be selected for the co-product. The available allocation type are given depending upon the characteristics of the co-product material selected.
If the displacement treatment method is selected, the Displacement material, Purpose, Mix and Displacement ratio parameters can be set for calculating the displaced energy and emissions. Few of the options can be unavailable depending upon the characteristics of the co-product displacement material selected. Any number of displacement materials can be added along with the specific fields for that displacement material.
See the full user guide under co-products for more information on co-product methods.
Removing a Co-Product
To remove a Co-Product from a process select the Add/Edit Co-Products button and navigate to the tab matching the desired resource to remove. Click the red "X" icon to delete the co-product and then hit Save or "Save and Close" to save the changes.