Ecoinvent 3.10 - Municipal incineration - states net energy production incl electricity but not in inputs or outputs

Question

The description for treatment of municipal solid waste, municipal incineration | municipal solid waste | APOS, U in FR( 09ab642c-77db-3f5f-96d1-3b59a2d550a3) says:

Net energy production: 1.39MJ/kg electric energy and 2.85MJ/kg thermal energy.

Can anyone explain why there is no electricity output in the process outputs section? Where we use incineration and it says there is a net electricity output in the description, do we still have to manually do system expansion to reflect the substitution of electricity that would have otherwise taken place? I have looked at lower levels but electricity doesn't appear on the Sankey diagram.

I have checked the Ecoinvent docs and Ecoinvent in OpenLCA seems to have faithfully reproduced it, so that doesn't seem to be the source.

Thanks in advance!

Answer 1

Because it is a multi-output process and the allocation is done according to the APOS system model. You will find the same process delivering "heat, for reuse in municipal waste incineration only" and anther process delivering "electricity, for reuse in municipal waste incineration only".

Comments

Hi cspringett,

I decided to use APOS for doing an LCA of several recycling systems. When using waste sorting activities, I realized the same as you, for one activity, there would be the unsorted waste input, but no sorted waste output. For the other sorting activity, there would be the sorted waste as product output, but no unsorted waste input. I do understand that treating waste and getting sorted waste as valuable product would be a multifunctional process. However, I do not understand, how to proceed with the modelling, as I want to model an unsorted waste input with some burden from the first life cycle and a sorted waste output, ready for chemical recycling, which I want to model.  I tried to find answers now for weeks, APOS seems very confusing to me and there are no good tutorials as far as I know. Since you had a very similiar question and seem to have understood Conrads answer, I wonder whether you could help me to understand this?

I would be very grateful. You could also email me, if more convenient for you. I am a PhD student at Max Planck Insitute in Magdeburg, my name is Ann-Joelle Minor

Best,
Ann-Joelle