When I calculate my results in the contribution tree and select 'Climate change' as the impact category, impact results only show for the system processes. I am getting null for unit processes.
I'm running the calculations for the growth of leafy greens using the ecoinvent 3.6 database. My system processes are plastics (HDPE & PVC granulates) and electricity (market for electricity, high voltage) while my unit processes include fertilisers (market for P2O5, N, K2O respectively), steel infrastructures (market for steel) and pumps (market for 40W pumps).
Are there changes I need to make to the process inputs in order to view their impacts in the results section?