ecoinvent EN15804 databases : Inherent LHV of secondary material

Question

Hi,

I am working with ecoinvent 3.11 EN15804 database.

I have a remark regarding inherent energy of secondary material. Although I could not find a normative definition of "primary energy" in EN15804 standard, inherent energy of secondary material has to be characterized, at least for EPD programs such as International EPD (see annex 3 of PCR 2019-14 construction products v1.3.4) and INIES (see annex M of NF EN 15804+A2/CN:2022, in French).

Secondary material (say non-renewable) come burden free (empty process). If I use elementary flow "Inherent LHV of declared product and packaging (non-renewable)" to model the corresponding material energy, it will characterize +1 on PENRM (ok), -1 on PENRE (not ok, should be 0) and 0 on PENRT (not ok should be +1).

In my view, there should be 2 additional elementary flows:

• "Inherent LHV of declared product and packaging (non-renewable), from or for secondary material", characterised +1 on PENRM and +1 on PENRT
• "Inherent LHV of declared product and packaging (renewable), from or for secondary material", characterised +1 on PERM and +1 on PERT

Let me know your view on this.

Best regards,

Jocelyn

Answer 1

Dear Jocelyn,

Thank you for your comment and that you already use the new EN15804 add-on that we released this week. We introduced the "Inherent LHV of declared product and packaging (non-renewable)" and "Inherent LHV of declared product and packaging (renewable)" elementary flows in the newest EN15804 add-on to facilitate the foreground accounting for PENRM/PERM. Usually PENRT/PERT is calculated over the whole supply chain by the cumulative energy demands (net calorific) whereas PENRM/PERM is calculated only for the foreground with the lower heating values of the declared product and packaging.

When you use this elementary flows in your own foreground, the declared primary energies will be automatically added to PENRM/PERM and automatically subtracted from PENRE/PERE, so that PENRT/PERT remain constant (as it is calculated from the primary energy over the whole supply chain, including background data) and only the share of material use and energy use will change. Because usually the declared primary energy is for the declared product or packaging, adding it to the PENRT/PERT indicators would lead to double counting, since these indicators already carry the primary energy from elementary flows somewhere deep in the supply chain (for example crude oil for the plastics production).

But I think you are right with your description of declaring inherent primary energy used as material from secondary materials. In this case (because SM come burden-free) there cannot be double counting and the same energy value should be added to both PENRM/PERM and to PENRT/PERT. The already existing elementary flows "Inherent LHV of declared product and packaging" should not be used for this, since they do not contribute to PENRT/PERT on purpose. In principle, the primary energy for secondary materials existed already in its previous life cycle, but e.g. EPD International asks to also declare the primary energy for secondary material inputs (which corresponds to the new life cycle).

We could create additional elementary flows called "Inherent LHV of secondary material (non-renewable)" and "Inherent LHV of secondary material (renewable)" which are added to PENRM/PERM and PENRT/PERT and not added to PENRE/PERE as you already pointed out.

Best wishes,

Conrad

Comments

We saw that EPD International also expects that recovered energy inputs in the foreground have to contribute to the primary energy indicators, so maybe to keep it more flexible for the modelers, we should call the elementary flow name "Inherent LHV of secondary inputs ..." instead of "Inherent LHV of secondary materials ...".

I also checked the new PCR 2019:14 v2.0.0 and annex 3 stays the same there.