ecoinvent Forum Archive

 Dear ecoinvent team,

I am working with the LCIA GWP indicators and when looking for a specific dataset I see several options, some datasets are named "Market" and I would like to understand the difference. I have looked at the UPR information but it is still not clear to me.

For example, in the "Market for diesel" dataset, does this include both extraction impact and distribution to petroleum station?

If I have to calculate the impact from Diesel A1 at an industrial plant, is the market dataset more accurate than "Diesel production, petroleum refinery"? 

Another case would be for sand, to calculate A1 impact for my system, when I am introducing distances and transport information from the sand quarry to my plant:  it is more accurate to use "market for sand" or "gravel and sand quarry operation"?

Thank you in advance for your support,

Best Regards,

Dear sust2021,

Thank you very much for your question.

To understand better how markets work in the ecoinvent database, I recommend you to read this FAQ: https://www.ecoinvent.org/support/faqs/methodology-of-ecoinvent-3/what-is-a-market-and-how-is-it-created.html

Ecoinvent differentiates between ordinary transforming activities and market activities.

Transforming activities are human activities that transform inputs, e.g. a hard coal mine that transforms hard coal in the ground to the marketable product hard coal. Transforming activities are here understood in the widest possible sense, including extraction, production, transport, consumption and waste treatment activities, i.e. any human activity where the intermediate output is different from the intermediate input.

In contrast, market activities do not transform their inputs, but simply transfer the intermediate output from a transforming activity to the transforming activities that consume this intermediate output as an input, e.g. from hard coal at the supplier to hard coal at the consumer. Market activities provide products that are supplied by an average mix of producers. Market activities also contain transportation of the product, if relevant. In general, it is recommended to use market activities if you do not know exactly which process is producing the product you are interested in.

I also recommend watching the following webinar Beginners Guide: Introduction to the ecoinvent database | 25.03.2021 available here: https://www.youtube.com/watch?v=0lVEf3yAIyM

Best regards,

Lea Wollensack

Junior Data Analyst, ecoinvent

Hi there,

I have a follow up question about market datasets. In the FAQ page, the market process shows inputs of product x, but when looking at the market processes in the database (e.g. market for petroleum, GLO), there is no input of petroleum.

When I run an impact assessment for this process, should I assume that upstream transformation impacts for the marketed product (e.g. extraction of petroleum) are included?

If so, I'm a little confused why the cumulative energy demand impacts for market for petroleum, GLO (a total of around 7 MJ/kg) are less than the CED impacts from the process petroleum production, onshore, GLO (around 8 MJ/kg) which I would assume is (one of) the main contributor(s) to the market.

Any help would be much appreciated!

Hi mikdale,

Thank you very much for your question. Markets are connected to their supplying activities during linking. When looking at the undefined unit processes (UPR), the markets do not have inputs other than transport and losses if applicable. The "linking" is the process that produces a linked system model out of the unlinked multi-output UPR datasets of the ecoinvent database. When you look at the same dataset with one of the system models selected, you will be able to see that linking has occurred and the dataset now has inputs of petroleum from all geographies/technologies producing petroleum.

You can read more about the linking process in the FAQs “What is linking and what happens during the linking process?” for the attributional and consequential system models respectively. You can also learn more in the following webinar: https://www.youtube.com/watch?v=aXdS4ohbvIk&t=1484s

In regards to your questions, yes, upstream transformation impacts for the marketed product (e.g. extraction of petroleum) are included, the datasets represent cradle-to-gate.

Best regards,

Lea Wollensack

Junior Data Analyst, ecoinvent