Log on to environdec

PCR Forum

Buildings

Allocation

by: Jannick Hoejrup Schmidt (jannick) 23 September 2013, 6:55:12 AM (GMT +1)

In the 'Draft PCR for open consultation' chapter 8 on page 18 it is written: "The method of avoiding allocation by expanding the system boundaries, as advocated in ISO 14044, is not applicable within the framework of the International EPD® System due to the rationale of the book-keeping LCA approach (attributional LCA) used and the concept of modularity."

Comment: This requirement is directly against ISO 14025 which is the core basis of the current PCR. ISO 14025 (section 5.3) states the following requirement: "The data shall be generated using the principles, framework, methodologies and practices established by the ISO 14040 series of standards (i.e. ISO 14040 and ISO 14044)." 
And according to ISO 14044, the modelling approach with the highest priority (after sub-division) is avoiding allocation by system expansion.

Kind regards,
Jannick H Schmidt, Associate Professor
Aalborg University
Denmark (jannick@plan.aau.dk)

Re: Allocation

by: Kristian Jelse (kristianjelse) 24 September 2013, 4:06:00 PM (GMT +1)

Dear Jannick,

I will answer this question instead of the PCR Moderator as it refers to the general LCA approach used in the International EPD® System and not only this PCR.

Your interpretation of the ISO hierarchy of different approaches of solving multifunctionality appears to be that system expansion is always equivalent to substitution/avoided emissions. As has been discussed in the LCA community for a long time, there is not always such an equivalence. If the substitution approach is applicable depends on the goal and scope of the study.

Environmental declarations is very much related to the attribution of impacts without interaction with other systems, why avoided emissions is not an option. Solving multifunctionality is therefore done through allocation.

For more information about the LCA approach of the International EPD System, please see the General Programme Instructions, Annex A.

Best regards,

Kristian Jelse,
Secretariat of the International EPD® System

Re: Allocation

by: Jannick Hoejrup Schmidt (jannick) 07 October 2013, 8:50:48 AM (GMT +1)

Dear Kristian Jelse, Thank you for your response. Comment #1 You wrote: “Your interpretation of the ISO hierarchy of different approaches of solving multifunctionality appears to be that system expansion is always equivalent to substitution/avoided emissions. As has been discussed in the LCA community for a long time, there is not always such an equivalence. If the substitution approach is applicable depends on the goal and scope of the study.” Comment: I think this comment is based on a misunderstanding. In a complete database / product system, there is per definition no possibility to expand the product system. System expansion refers to the situation of incomplete product systems (which were quite normal at the time when ISO standards on LCA and EPD were written) where substitution required the addition of the missing activity datasets to be substituted, hence the name system expansion (example: System A has an activity A with the single output product A. System C has an activity C that jointly produce product A & product B. One or both of the systems are incomplete in the sense that they do not contain the single-output activity B that produces B alone. In order to compare product A produced from system A with product A produced from system C, it is necessary to add the missing activity B to the incomplete system, so that the system can be modelled as having only the same outputs of A and B. This is system expansion. However, if the systems were already complete (as our LCA databases are today), activity B would already be an input to the upstream of activities A and C, and the comparison would not require the addition of activity B, but simply to change its production volume so that the output of the two systems match. This is substitution. As you can see the only difference is in the completeness of the original systems. Comment #2 You wrote: “Environmental declarations is very much related to the attribution of impacts without interaction with other systems, why avoided emissions is not an option. Solving multifunctionality is therefore done through allocation.” Comment: In section 10.4 of the draft PCR it appears that substituted production IS included in the module D. There are two methodological problems related to this: 1) Module D gives the opportunity to include the benefits of recycling two times = double counting (if recycling materials are used for the building AND if these materials are recycled at end of life of the building). 2) Substitution in end of life stage is in compliance with ISO 14044 and ISO 14025, but it is inconsistent with all other modelling of co-products in the PCR (allocation). Module D give the opportunity to apply different modelling assumptions to the acquisition of materials and disposal/recycling of the same materials. The effect of this is that double counting of recycling benefits is possible (see 1 above).

Re: Allocation

by: Kristian Jelse (kristianjelse) 17 October 2013, 2:59:18 PM (GMT +1)

Dear Jannick, Yes, indeed, Module D is in fact an inconsistent LCA approach considering strictly attirubtional vs. consequential LCA modelling. This arises from the methodological choices made when developing the EN 15804 standard for core product category rules for construction products. The fact that this inconsistency exists, and how to handle it, is currently being discussed in Sweden in the industry consensus project "Robust LCA", as managed by IVL. There is currently a draft version of the report circulating. If you contact the project manager, martin.erlandsson@ivl.se, I am sure he would be happy to send you a copy of the draft or the final report, when ready. Best regards, Kristian

3 Posts Page 1 of 1

Answer