Calculation og biogenic carbon content and cutoff rules for biogenic carbon content input for a product

Question

Greetings.

I want to calculate the biogenic carbon content in my product using the OpenLCA. However there are a lot of processes that might have such an input in my product. How can I understand which of them affect the amount of  biogenic carbon in my product, and next, how can I calculate it. I use the ecoinvent 3.8 and EuGeos 15804 databases.

Additionally, because my product is a construction product, there is a cut-off rule of 1% according to the EN 15804 standard, about the mass input. Does this also affect the biogenic carbon mass input, meaning that if it lower I can consider it negligible?

Thanks a lot for your time.

Answer 1

Interesting - you could make a net calculation of the processes where biogenic carbon is input or output, considering the biogenic carbon for all input and output flows. The difference is then the change of biogenic carbon in your product.

1%: this is only a threshold that is not to be exceeded, it is not so that you need to meet the 1%. But it applies also to biogenic carbon.

In case of insufficient input data or data gaps for a unit process, the cut-off criteria shall be 1 % of [...]  the total mass input of that unit process.

(EN15804 A2)

Comments

First of all, thank you Mr Ciroth for your time.

How can I identify the biogenic carbon in an input or output process in order to know its existence and then its amount?. Is there a specific flow I can search in each process?

Until now, I have been calculating each product system and then checking through the contribution tree tab about the different amounts. Maybe there is a flow there that represents biogenic carbon "In disguise"?

Thank you for your clarification about the cut-off rule and your continuous support.