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Trust in Transparency! 1
Impacts of modeling choices versus
data updates in a large data system
LCAXV, Vancouver
06 October 2015
Gregor Wernet Bernhard Steubing
Executive Manager Senior Research Associate & ecoinvent LCI Expert
ecoinvent ETH Zurich
The world’s most
consistent and
transparent Life Cycle
Inventory database
Impacts of modeling choices versus
data updates in a large data system
LCAXV, Vancouver
06 October 2015
Gregor Wernet Bernhard Steubing
Executive Manager Senior Research Associate & ecoinvent LCI Expert
ecoinvent ETH Zurich
Trust in Transparency! 3
What is ecoinvent?
• ecoinvent is a not-for-profit association created by 5 Swiss
research institutes
• Publishes, maintains and updates the ecoinvent database
Trust in Transparency! 4
ecoinvent – Quality Features
• Consistent
Fully interlinked database
• Reliable
Independent expert review for all data
Continuously developed and improved over 15 years
• Transparent
Full access to both unit process data and all calculation results
Individual documentation of each dataset
Trust in Transparency! 5
Development of version 3
• Develop the database into a global database
Change in scope
• Allow more flexibility for the users
More access to the underlying modelling
Flexibility in modelling choices
• Many data updates in the 3 years between version 2.2 and 3.0
• Combination of several methodological updates and many data
updates makes it difficult to understand the differences!
Trust in Transparency! 6
Version 2.2 vs Version 3 (cut-off)
Trust in Transparency! 7
Some changes with version 3
• Waste flows with mass
• System models
• Global supply chains
• Consumption mixes and markets
• Update of transport data
• Data updates
Trust in Transparency! 8
System models in ecoinvent v3
• Allocation, Recycled Content cut-off
• Allocation at the point of substitution (APOS)
• Consequential (long-term, small-scale)
• The cut-off model is identical to v2.2 in its approach
Only minor consistency corrections affecting individual datasets
Trust in Transparency! 9
Cut-off vs APOS
• Difference in allocation of wastes treatment products and
recyclable materials
No other differences in the models
• Differences only for these products
8% of products in the database are wastes, few have significant by-
products in treatment
2% of products in the database are recyclable materials
Trust in Transparency! 10
Cut-off vs APOS
APOS divided by Cut-off
Trust in Transparency! 11
Some features of version 3
• Waste flows with mass
• System models
• Global supply chains
• Consumption mixes and markets
• Update of transport data
• Data updates
Trust in Transparency! 12
Global supply chains
• In v2.2, local datasets served as placeholders for global
activities
• All processes now have a global counterpart
Often extrapolated from regional data
Uncertainties increased
Distributes supply chains and impacts for regionalized LCIA
Serves as a foundation for regional data collection projects
• Supply chains can access these globalized sources
Trust in Transparency! 13
• Comparison of Cut-off results v2.2 vs v3.1
• Globalized supply chains more relevant in v3.1
Impacts in e.g. China more accurately reflected
Global supply chains
Trust in Transparency! 14
• Changes in allocation method
Switch from mass to economic allocation
• Not a violation of the ISO principles, only for datasets where
there is no physical relationship between mass and the process
drivers.
Most physical properties are not allocation-relevant
Example: Lithium chloride electrolysis
Data updates - allocation
Trust in Transparency! 15
• Some datasets were restructured
e.g. port maintenance is now included in the port infrastructure
Impacts significantly increased over the lifetime of the port
Burden of transition to new modelling, but significantly easier to use
datasets for the practitioner
• Many datasets were simply improved and expanded
Updated data can improve – or get worse – LCIA results
• Introduction of new consumption mixes has impacts on individual
datasets
• Thousands of datasets were updated for version 3, and no single
change can explain a large part of the differences between versions
Data updates - restructuring
Trust in Transparency! 16
Data updates - Transport
• Global update of freight transport data
Based on sector-specific transport statistics
Trust in Transparency! 17
Some features of version 3
• Waste flows with mass
• System models
• Global supply chains
• Consumption mixes and markets
• Update of transport data
• Data updates
Trust in Transparency! 18
Conclusions
• Differences between ecoinvent versions 2 and 3 can be difficult to
explain due to the many changes introduced with version 3
• Several methodological changes and also some data projects have
had no or barely any effect on results
Waste modelling, System model implementation, Transport data
• The expansion of the database towards global supply chains has
corrected serious issues with supply chains as well as distributions
of impacts
• Data updates and additions are the main reason for significant
changes in version 3
The world’s most
consistent and
transparent Life Cycle
Inventory database
Thank you for your attention!