I am currently working on my first LCA project on OpenLCA, in which I want to calculate the yearly environmental impacts of vegetables production in a greenhouse. I am using a mix of manually created flows and existing database flows. So this is my problem: Regarding infrastructure flows and machinery/miscellaneous items, which is a proper way to distribute the impacts of their manufacturing/construction on a year, given that I know their lifetime? For example, If I have calculated that the construction of my greenhouse (lifetime=20 years) emitted 5 tons of CO2 into the atmosphere, does that mean that for my study (1 year vegetable production) I have an output of 5/20=0,25 tons of CO2 by this flow? If not, which is the "formula" or the right way to do this adjustment? Does the OpenLCA software provide a way of adjusting the lfietime impacts of these flows?
Thank you in advance!