ecoinvent Forum Archive

Hi,

My name is Nathanael and i'm currently working on a project in CRIG, at Liège, which is analysing the impacts of extraction of Silica as a raw material to implement it in a LCA for Multi-Si Panel. For this, i'm comparing the litterature with the database and i saw that in ecoinvent, the raw material use for Solar panel industry was based on Silica sand extracted for construction industry (with a huge part coming from Brazil). However, the litterature is talking about "High purity Quartz" or "Quartz with a relative amount of impurities" and talk about criticality of Silicon.

So i have some questions that maybe you'll be able to answer:

Is there any difference between the process implemented into Solar panel value chain and into construction one ? I mean, is the process "Silica Sand" used as provider for Solar Panel the same when used as well as a provider for glass making or contruction material for building ?

Is this process taking into account these purity differences and availability or it needs an update and for the moment, the assumption of taking one process for all type of Silica Sand is made ?

How criticality/ressource depletion is implemented into the database ?

 Do you have a report on the implemention, in ecoinvent, of silica sand for the making of MG-Silicon (which is the basic material for the making of Multi-Si on Mono-Si solar panel) ? 

Would it be possible to contact the person who worked on the "information adding" of this process ? 

Thanks in advance for your answers.Best regards,Nathanael

Dear Nathanael,

Thank you for your question. By taking a closer look at the supply chain of solar panels production process included in the database, they have silicon, metallurgical grade as input in the datasets. Metallurgical grade means that silicon has a purity of over 99%, based on carbothermal reduction process of silica sand. Thus, it is different from the silica sand used in the building materials and glass production. You can find more details about the “silicon production, metallurgical grade” (MG-Silicon) by checking the dataset modelling it production and its available documentation (report No 6 Sachbilanzen von Energiesystemen. Final report No. 6 ecoinvent v2.0) which contains supplementary information to the metadata in the dataset.

Regarding resource depletion, there is no specific information on the criticality of minerals or metals provided currently at the database. It can only be assessed through the impact assessment methods included in the database with the relevant characterization factors. You can take a look at the LCIA implementation file that documents the methods and the characterization factors used.

Best regards,

Nikolia Stoikou, Junior Data Analyst, ecoinvent association