For each dataset in the ecoinvent database, the list of elementary exchanges (natural resource inputs and emissions to the environment) can be assessed with Life Cycle Impact Assessment (LCIA) methods.
Oct 25th, 2023
For example “IPCC 2021”, “EF v3.1”, or “ReCiPe 2. This gives an indication of the environmental impact that is caused by an activity. Impact assessment methods can a) focus on a single impact or environmental footprint such as the carbon footprint or the water footprint, or b) include several impact categories such as “climate change”, “human toxicity”, “land use”, or “water use”.
Footprints and impact categories can be assessed with different indicators, for example “global warming potential 20 years (GWP20)” or “global warming potential 100 years (GWP100)” in case of the carbon footprint or the “climate change” impact category. Each indicator has a unit, for example kg CO2-equivalents.
The factor converting an elementary exchange into an amount of kg CO2-equivalents is called “characterization factor” (CF). In the “IPCC 2021” method, fossil methane has a CF of 29.8 kg CO2-equivalents / kg methane for the “global warming potential 100 years (GWP100)” impact category. Applying CFs to all relevant elementary exchanges in an impact category, an impact assessment score (or result) can be calculated, for example a carbon footprint of 34 kg CO2-equivalents. In case of emissions such as CO2-equivalents, this score is sometimes also referred to as “emission factor”.
Some methods including several impact categories, for example “ReCiPe 2016”, offer a further aggregation into damage categories or “Areas of Protection” (AoPs). These are usually called “human health”, “ecosystem quality”, and “natural resources” (or similar). Finally, these results can be further aggregated into a weighted total.
Methods Implemented in ecoinvent
We provide scores (or results) for several impact assessment methods. Details can be found in the database overview file. Implementing methods includes the mapping of elementary flows from methods onto elementary flows from ecoinvent (for example, “Trichloromethane” to “Chloroform”). We have published these mappings on GitHub. These files can be used for analysis, review, or implementation by method developers, software developers, scientists, and other users. We hope this will increase transparency, collaboration, and, ultimately, the quality of method implementation in the ecoinvent database.
If you would like to see your method implemented in the ecoinvent database, you can do so by simply providing the method via the ecoinvent LCIA method input format or by using the latest ecoinvent elementary flow list in the database overview file.
CML is the Institute of Environmental Sciences of the University of Leiden in the Netherlands. The CML method was first developed in 1992 and updated to its current version in 2016. It is a midpoint method assessing several impact categories. More information about the method can be found here, and the characterization factors can be found here.
Crustal Scarcity Indicator
The Crustal Scarcity Indicator was developed in 2020 by Rickard Arvidsson and colleagues at Chalmers University in Gothenburg, Sweden. The method assesses mineral resource use based on crustal concentrations, which is considered a proxy for long-term global elemental scarcity. More information about the method and the latest characterization factors can be found here, the characterization factors can be found here.
Cumulative Energy Demand (CED)
Cumulative Energy Demand (CED) is based on the method published by ecoinvent for version 1.01 in 1997. It assesses primary energy usage.
Find more information in the ecoinvent v2.2 method implementation report.
Cumulative Exergy Demand (CExD)
Cumulative Exergy Demand (CExD) is based on the publication by Bösch et al. 2007. It “assesses the quality of energy demand and includes the exergy of energy carriers as well as of non-energetic materials”. Thereby, exergy “accounts for the minimal work necessary to form the resource or for the maximally obtainable amount of work when bringing the resource’s components to their most common state in the natural environment.”
Ecological Footprint is defined as the biologically productive land and water a population requires to produce the resources it consumes and to absorb part of the waste generated by fossil and nuclear fuel consumption. The method was developed in 2006 and it assesses the direct land occupation as well as the indirect land occupation related to the sequestration of CO2 emissions and nuclear energy use in the unit of “global hectares”. More information about the method can be found here.
The Ecological Scarcity method was developed for Switzerland by the Federal Office for the Environment (FOEN) in 1990 and it was updated to its current version in 2021. It is a “distance to target” method considering the current situation and political targets (concerning emissions and resource use) for Switzerland (or by international policies and supported by Switzerland). The method assesses several impact categories in eco-points (“Umweltbelastungspunkte” or UBP), which is why results can be summed into a total. More information about the method can be found here.
Ecosystem Damage Potential
The Ecosystem Damage Potential method was developed by the Swiss Federal Institute of Technology (ETH) in 1997. It assesses land occupation and transformation. More information about the method can be found here.
EF stands for Environmental Footprint and the method is maintained by the European Commission. Versions 3.0 and 3.1 are implemented in ecoinvent. It is a midpoint method assessing several impact categories. More information about the method and the characterization factors can be found here.
ecoinvent has developed a system model called “Allocation, cut-off, EN15804”. The aim of this system model is a) to facilitate Environmental Product Declaration (EPD) practitioners to comply with the standard EN15804&A2:2019, and b) to contribute to a harmonization in the calculation of the indicators of the standard.
ecoinvent provides two impact assessment methods for the “Allocation, cut-off, EN15804” system model: the EF v3.0 EN15804 method, which provides the LCIA scores based on the Characterization Factors provided by the European Commission, and the EN15804 (inventory indicators ISO21930) method, which provides the resource indicators required in EPDs. The latter are not impact assessment indicators but are included in an impact assessment method to be more easily accessible to the users.
More information about the EF v3.0 EN15804 method and the characterization factors can be found here. Further documentation about the system model and the method implementation can be found in a dedicated report (if you log-in on ecoQuery under "Files" section).
Important note: the EN15804 impact assessment methods are meant to be used only with the EN15804 system model.
EPS stands for Environmental Priority Strategies. The method was developed by the Swedish Energy Agency, FORMAS. It was first released in 1990 and updated to its current version in 2020. It is an endpoint method assessing economic damage caused by emissions as well as the use of energy and material resources and land. More information about the method can be found here, and the characterization factors can be found here.
The IPCC is the Intergovernmental Panel on Climate Change by the United Nations. The panel regularly releases Assessment Reports (ARs) containing emissions metrics for Global Warming Potential (GWP) and Global Temperature Change Potential (GTP). These numbers are implemented as the IPCC method. More information about IPCC 2021 can be found in AR6 here.
ReCiPe was developed by the Dutch research institute of RIVM (National Institute for Public Health and the Environment), Radboud University Nijmegen, Leiden University and Pré Consultants in 2008. It was updated to its current version in 2016. It is a midpoint and an endpoint method, and it considers three different cultural perspectives: individualist (I), hierarchist (H), and egalitarian (E). The method assesses several midpoint impact categories and the three areas of protection human health, ecosystem quality, and natural resources at endpoint level. More information about the method can be found here, and the latest characterization factors are available here.
TRACI stands for Tool for the Reduction and Assessment of Chemical and other environmental Impacts. It is a method published by the U.S. Environmental Protection Agency (US EPA), originally released in 2002 and updated to v2.1 in 2012. It is a midpoint method assessing several impact categories. More information about the method and the latest characterization factors can be found here.
Legacy methods are still published, but not maintained anymore. This means that a) if an error is reported, it will not be corrected; and b) if a new elementary exchange is added to ecoinvent, legacy methods will not be checked for a CF match with the new exchange. Read more about these methods and their original implementation in the ecoinvent v2.2 method implementation report.
EDIP stands for Environmental Development of Industrial Products and it was developed by the Institute for Product Development (IPU) at the Technical University of Denmark in 1997. It was updated to its current version in 2003. It is a midpoint method assessing several impact categories. More information about EDIP 2003 can be found here.
IMPACT stands for IMPact Assessment of Chemical Toxics and it was developed by the Swiss Federal Institute of Technology – Lausanne (EPFL). IMPACT 2002+ was released in 2002. It is a midpoint and an endpoint method, assessing several midpoint impact categories and the three areas of protection human health, ecosystem quality, and natural resources and – additionally – climate change at endpoint level. More information about the method can be found here.
Selected LCI Results
Selected life cycle inventory indicators are in most cases “the summation of selected substances emitted to all different subcompartments. In some cases, different substances are added up to quantify frequently used parameters such as non-methane volatile organic carbon (NMVOC), selected radioactive species or particulate matter” as Hischier & Weidema state in the ecoinvent v2.2 method implementation report.
USEtox was developed by the United Nations Environment Programme (UNEP) and Society of Environmental Toxicology and Chemistry (SETAC) to assess the fate, exposure, and effects of chemicals in Life Cycle Impact Assessment and Comparative Risk Assessment. It assesses human toxicity and freshwater ecotoxicity impact categories at midpoint and endpoint level whereby only midpoint results are implemented in ecoinvent. More information about the method can be found here.