This support post is part of the Modelling Carbon Neutral Construction in eTool article series in which the focus is on How to Model Carbon Offsets for Remaining Impacts.
Carbon offsets for remaining impacts
Depending on your budget and how much impact remains after all other carbon reduction strategies (including other carbon offsets) have been considered, you may want to offsetting the remaining impacts for your project by purchasing carbon offsets directly.
Carbon offsets deviate from the EN15978 standards. Therefore, carbon offsets as a design strategy need to be modeled as a scenario outside of the headline of the LCA.
Below is a step-by-step method to model carbon offsets for remaining impacts for your LCA study.
Step 1: To calculate the total remaining impacts to be offset, navigate to the Analysis tab of the scenario design to extract the GWP figure for remaining impacts.
Step 2: Create a new custom EPD with remaining impacts in NEGATIVE values and add into the design. Note that the quantity of the EPD should be set as #1 and the Product Service Life of the EPD needs to be the same as Predicted Service Life (study period) of your LCA. For more information about how to create a new EPD in eTool, please refer to this support post. Below is an example of the EPD for Offsetting of Remaining Impacts.
Step 3: After adding the EPD into the design, navigate to the Analysis tab again, you can see that all remaining impacts have been offset.
To generate the LCA report for carbon neutral/offset scenarios, please refer to the following post: