Emission Factor Uncertainty

Where uncertainty estimates are available by the publication source, these values are used.

However, when these estimates are not available, a best-effort single parameter uncertainty estimate is performed using GHG Protocol methodology, using context and data available in methodology documents.

In a similar way to how volume uncertainty levels are organised, EF uncertainty in Carbon+Alt+Delete follows a predefined list of reference options to keep classification transparent, traceable, and manageable.

For each option, an emblematic example is central to define the context in which this uncertainty option is applicable. You can find these examples in the table below, together with their individual indicator scores for each of the uncertainty indicators. For EF uncertainty, two more parameters come into play; the Basic Uncertainty Factor Process Type, reflecting a general industry-wide average uncertainty, as well as the share of non-CO₂ emissions in each factor, reflecting the scientific uncertainty of non-CO₂ GWP values.

Please note at that EF uncertainty in the tool reflects both emission factor and GWP uncertainty. For more info, see background and theory.

For the source of the uncertainty factors and the definitions of each parameter in the pedigree matrix, please consult the following sources.

GHGP Quantitative Uncertainty Guidance

GHGP Scope 3 Uncertainty Calculation Tool

Section 7.3 of Ecoinvent v2.0 data model methodology (referenced source for pedigree matrix)

EF uncertainty

Emblematic example

Reliability

Completeness

Temporal rep.

Geographical rep.

Technological rep.