Monetary Impact Factors

Monetary Impact Factors

Monetary impact factors estimate the inventory (commodity) quantities used to produce a given purchase or turnover amount expressed in monetary terms, using the EXIOBASE environmentally-extended input-output model. They cover Scope 1 and Scope 3 upstream, but not Scope 3 downstream.

EXIOBASE data access

• EXIOBASE product version (IOT_2022_pxp) is used.
• Emissions and commodities can be referred to in as EXIOBASE is an Input-Output Model Environmentally Extended, it gives access to environmental stressors generated and exchanged by the different products in the different regions.
• EXIOBASE stressors are of different nature: emissions, commodity flows (raw materials), social and energy linked flows.

Reminder on EXIOBASE matrices

• x : total production
• F : total stressors Scope 1 (quantities of stressors) for total production (dimension 1300 x 10000)
• L: Leontiev matrix
• F/x = S : total stressors Scope 1 per million EUR
• M = S.L : total stressors Scope 1 + 3 per million EUR
• S x A : total stressors for Scope 3 rank 1 per million EUR

Scope 1 (S) and Scope 3 (M - S) requirements are computed and stored to be used for future computation allowing the separation of Scope 1 and Scope 3 stressors.

EXIOBASE stressors mapping into Ecoinvent framework

Among the stressors, we do not map:

• Social stressors.
• Energy linked flows (unit TJ): Nature inputs, emission relevant energy carrier, energy carrier supply, energy carrier used. It would lead to double counting as emissions already include energy production processes.

Emission type mapping

• GHG and pollutants
  • For GHGs and pollutants, we do a mapping based on the molecule/compound (ex: CO2) and emission compartment (ex air or soil). They both have to match in ecoinvent elementary flows table.
  • We do not differentiate combustion and non combustion emissions.
  • For ecoinvent sub compartment, "Unspecified" is chosen by default.
  • HFC/PFC are pre-aggregated by EXIOBASE in CO2-equivalent and mapped accordingly.
  • Particulate emissions are reported by EXIOBASE as cumulative size classes (PM2.5, PM10, TSP); Darwin rebuilds them into non-overlapping size classes (< 2.5 / 2.5–10 / > 10 μm) to avoid double-counting the fine fraction.
• Water
  • Water account distinguishes extractions of green water (coming from evapotranspiration of the vegetation), blue water (coming from water bodies). Considering that the elementary flows in ecoinvent concern the water abstracted from rivers and wetlands, only blue water is considered.
  • Water account distinguishes withdrawal and consumption. In ecoinvent, as the mapping is done with only one "input" from biosphere, only net flow is considered, ie consumption.

Commodity type mapping

• Only "used domestic extractions" are mapped, not "unused domestic extractions"
  • EXIOBASE distinguishes two types of extractions: the "used domestic extraction" and the "unused domestic extraction". The first type documents the actual quantity of raw material extracted (e.g. tonnes of carrots) while the second one refers to the amounts that come with the raw materials of interest but are not used (e.g. stems, leaves and other residuals of biomass extraction, overburden for mining activities). Ecoinvent activities are set for quantities of used products like cultivated carrots or extracted ores (without the overburden) considering impacts of the full process including used and unused parts of the product). Therefore to capture the pressures and impacts, we only need mapping the used domestic extractions.
• Commodity type stressors are mapped with darwin's proprietary commodity list. Adjustments are made to account for:
  • mismatch on the transformation level, for instance gold ore in EXIOBASE matched with gold unrefined metal with an adjustment factor reflecting the average grade of gold ore,
  • unit mismatch, for instance for wood weight in EXIOBASE needs to be converted into cubic meters to match ecoinvent associated product, therefore density assumptions have to be taken.
• Metal ores follow the gross-ore (run-of-mine) convention (Stadler 2018): EXIOBASE reports crude-ore tonnage, so an adjustment factor (metal content in ore / metal content in the target activity) is applied. Targets are ecoinvent mine or concentrate activities, never market for … activities.
• For crops and biomass, country-specific production activities are preferred over Rest-of-World proxies when the latter carry allocation-by-substitution artefacts (negative LCI contributions).
• Fossil fuels are reported by EXIOBASE as a single aggregate extraction. Darwin splits this aggregate into fuel-specific commodities (hard coal grades, lignite, crude oil, natural gas, natural gas liquids, peat) using a country-level fossil mass-mix (OWID / Energy Institute Statistical Review, 2022), so each fuel maps to its specific ecoinvent production activity.

Impact factor computation

Pressures and impacts are computed from the commodity inventory (via the product/pressure models), then combined with the EXIOBASE direct stressors. To avoid double-counting, the accounting differs by pressure category:

• Climate change (GHG): total = commodity + ex-commodity, where the ex-commodity part is the EXIOBASE direct LCI stressors (Scope 1 + Scope 3) beyond what the commodity inventory already captures.
• Land use, water and pollution (non-GHG): total = commodity only. The EXIOBASE non-GHG direct stressors are excluded, since these impacts are already captured by the commodity product model.

Results are structured for Scope 1 and Scope 3 upstream: commodity inventory; impacts and pressures linked to the commodity inventory (available at commodity level); and impacts and pressures ex-commodity.

What value chain do we cover?

Monetary impact factors are computed with the EXIOBASE input-output framework:

• Scope 1 — Direct operations: stressors directly generated by the production activity (matrix S).
• Scope 3 upstream: stressors embedded in supply chain inputs across all upstream ranks (matrix M − S).

Scope 3 downstream — product use phase, distribution and end-of-life — is not covered by this module.