A Survey of Industry Data Models and Reference Data Libraries

13  Life Cycle Assessment

13.1    European Platform on Life Cycle Assessment

https://eplca.jrc.ec.europa.eu/

The European Platform on Life Cycle Assessment (EPLCA) has two roles:

1.      provide environmental impact information to support life cycle assessment of products and organizations;

Some of the information is specific to the EU, but much of the information is of general world-wide applicability.  The introduction to the platform says:

The EPLCA is the EU’s knowledge base that responds to business and policy needs towards sustainable production and consumption.

2.      define a way of carrying out life cycle assessment.

The approach is general, although its use is mandated in EU directives.  The approach defines the process for assessing environmental impacts and the International Life Cycle Data format for holding the data.  The introduction to the platform says:

The EPLCA supports the methodological development of Life Cycle Assessment (LCA) for the analysis of supply chains and end-of-life waste management.

The overall objectives of the European Platform on Life Cycle Assessment are summarised in Figure 13.1.

Figure 13.1 - European Platform on Life Cycle Assessment

The information within the European Platform on Life Cycle Assessment is intended to be part of an ILCD (International Life Cycle Data) Network.  The system is described by the ILCD handbook.  The two roles of the platform are described separately in the following sections.

13.2    International Life Cycle Data (ILCD) system

https://eplca.jrc.ec.europa.eu/ilcd.html

13.2.1   Defining organization

European Union, DG Environment and JRC Ispra

13.2.2   Objectives and scope

The introduction to the ILCD says:

The ISO 14040 and 14044 standards provide an important framework for LCA.  This framework, however, leaves the individual experts, practitioners and data developers, with a range of important choices that can be individually interpreted, leading towards differences in consistency, reliability and comparability of the results of the assessment.  Equally, the methodological assumptions behind the life cycle data can differ widely, so that data from different sources can be not interoperable.

The International Reference Life Cycle Data System (ILCD) is an initiative developed by JRC and DG ENV since 2005, with the aim to provide guidance and standards for greater consistency and quality assurance in applying LCA.

There are two parts of the ILCD system – the process and the ILCD format:

• the process is defined in the ILCD handbook:

https://eplca.jrc.ec.europa.eu/uploads/JRC-Reference-Report-ILCD-Handbook-Towards-more-sustainable-production-and-consumption-for-a-resource-efficient-Europe.pdf

• the ILCD format is defined by schemas and stylesheets which can be downloaded from:

https://eplca.jrc.ec.europa.eu/LCDN/developerILCDDataFormat.xhtml

The objectives of both the process and the format which supports it are as follows:

1.      To record the flows into and out of an activity as shown in Figure 13.2.

Figure 13.2 - Flows into and out of an activity

The flows may be products of other activities or elementary flows from and to the environment.

2.      To trace back along the supply chains to find all the elementary flows from and to the environment, as shown in Figure 13.3:

Figure 13.3 - Flows from and to the environment

3.      To combine the elementary flows from and to the environment to give a single environmental Life Cycle Impact for a category, as shown in Figure 13.4.

Figure 13.4 - Life Cycle Impact

Comments on Figure 13.2, Figure 13.3, and Figure 13.4:

1.      The magnitudes of the flows are normalised with respect to a reference output magnitude, such as 1 kg of tinplate, or 1 MJ or electricity.

2.      A flow can be a flow of material or energy.  Some things that are not flows, such as the occupation of land for a period of time, are nonetheless referred to as “flows”.

3.      In order to produce a single magnitude for the impact on climate change each flow of a substance to the atmosphere is normalised to an equivalent CO₂ magnitude.  This normalisation depends on the time scale because different substances remain in the atmosphere for different periods of time.  Usually it is the 100 year magnitude that is considered.  The equivalent CO₂ normalisation factors for different substances are published by the IPCC – see https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter08_FINAL.pdf .

4.      The different Life Cycle Impact categories for using within the EU are described in  https://eplca.jrc.ec.europa.eu/permalink/PEFCR_guidance_v6.3-2.pdf .

13.2.3   Structure of the model

The ILCD data model is based upon ISO 14048:2002 “Environmental management — Life cycle assessment — Data documentation format” (https://www.iso.org/standard/29872.html).  This standard does not purport to be a data model, but instead:

“specifies requirements on division of data documentation into data fields, each with an explanatory description.”

The data fields are grouped into “data categories” as shown in Figure 13.5.

Figure 13.5 - ISO 14048 data categories

The numbers in Figure 13.5 are the clauses within ISO 14048 within which the data fields relevant to the category are documented.

The ILCD data model is a set of XML schemas which is closely aligned with the ISO 14048 data categories and fields.  The structure of these schemas is shown in Figure 13.6 and Figure 13.7.

Figure 13.6 - ILCD process data set

Figure 13.7 - ILCD impact assessment data set

Comments on Figure 13.6 and Figure 13.7:

1.      The information about a process is normalised by a “quantitative reference” to one of the flows.  For tinplate production, the quantitative reference is 1 kg of tinplate output.

2.      The origin or destination can be another process, or the environment.  This is defined by the flow data set.

3.      The “classification” specifies the destination of the flow.  This has the form of three levels specified by text strings.  The classification of many gaseous emissions data sets has the form “emissions/emissions to air/emissions to air, unspecified”.

4.      The “name” specifies the nature of the flow.  The name can be the name of a substance, or of a product such as “tinplate” or “electrical energy”.  In the case of a substance, the CAS number can be specified.  In some cases, the name encodes other information.  Hence there are different flow data sets with the names “carbon dioxide (biogenic)” and “carbon dioxide (fossil)”, but with the same CAS number and classification.

5.      The information about life cycle impact normalised by a “quantitative reference” to a flow property data set, which defines the measure.  For climate change, this is CO₂ equivalent mass.

6.      For processes which produce more than one product, emissions are allocated to the different products.  This is supported by the data models, but is not shown in the figures.  The data held in the LCDN is largely expressed in terms of single product processes.

The only objects in the data model that are assigned identifiers are:

• processes;
• flows;
• LCIA methods; and
• flow properties.

The objects have UUIDs and “permanent data set URIs”, so theoretically they can be defined once and referenced as needed.  However the style sheets and toolkits supplied with the ILCD schemas, assumed that processes, flows, LCIA methods, and flow properties are 4 subdirectories of the same root.  This results in each implementation having its own copy.

In many cases, the “permanent data set URI” references the European Life Cycle Database (ELCD), which has been withdrawn and so is not dereferencable.

In general, the data model is tied to the ISO 14048 document structure, and does not make explicit the principal features common to all process systems:

• processes have sub-processes;
• processes have input and output flows;
• a flow is of something;
• a flow is from a source (repository or process) to a destination (repository or process);
• flows can divide and can merge.

13.2.4   Documentation

The ILCD handbook is comprehensive and contains useful examples – see Figure 13.8.

Figure 13.8 - ILCD handbook

It is dowloadable from:

https://eplca.jrc.ec.europa.eu/uploads/JRC-Reference-Report-ILCD-Handbook-Towards-more-sustainable-production-and-consumption-for-a-resource-efficient-Europe.pdf

However, there are no schema diagrams because the schemas are regarded as merely a way of encoding the fields defined by ISO 14048.

13.2.5   Maintenance and usage

ISO 14048 was published in 2002, and has not been revised.  The latest of the guides to the use of the schemas was published in 2012.  The copyright date on the schemas is 2009.  The Software Development Tookit is version 2.1.1 is described as “new” but no dates are given.

It is not known whether the data models are used outside the European Platform on Life Cycle Assessment.

13.3    European Life Cycle Data Network (LCDN)

https://eplca.jrc.ec.europa.eu/LCDN/

13.3.1   Defining organization

European Union, DG Environment and JRC Ispra

13.3.2   Objectives and scope

13.3.2.1    Network as a whole

The introduction on the LCDN website says:

The LCDN aims to provide a globally usable infrastructure for the publication of quality assured LCA [Life Cycle Assessment] dataset (i.e. LCI [Life Cycle Inventory] datasets and LCIA [Life Cycle Impact Assessment] method datasets) from different organizations (e.g. industry, national LCA projects, research groups, and consultants).

The LCDN is a registry of nodes maintained by different organizations which contain datasets about flows and about impact assessments.  The introduction says:

All datasets registered and published are compliant with quality requirements aimed at guarantee datasets quality and coherence in terms of Methodology, Documentation, and Nomenclature, for the two compliance systems allowed (ILCD entry level and PEF/OEF [Product Environmental Footprint/Organization Environmental Footprint]).

Comment on the introduction are as follows:

1.      The “ILCD entry level” is the information about the flows, also called the Life Cycle Inventory, and has a minimum level of quality assurance.  The “PEF/OEF” has a higher level of quality assurance, and is linked to flow properties relevant to impact assessment.

2.      The documentation is not explicit about who ensures compliance with quality requirements.  Nonetheless individual data sets have information about an “independent review panel” and “quality indicators”.

The predecessor to the LCDN was the European Life Cycle Database (ELCD).  This was created in 2006 and withdrawn in 2018 on the grounds that “data developers (involved in ELCD data generation) [have the capacity] to create and maintain their own nodes for data sharing”.  The contents of the data base have been archived as at https://eplca.jrc.ec.europa.eu/ELCD3/.  Unfortunately, many flow data sets in the current data network have URIs that reference the withdrawn ELCD, and are therefore not dereferencable.

13.3.2.2    Environmental footprint

Key data to support life cycle impact assessment (environmental footprint) is published by the EU within the LCDN - see https://eplca.jrc.ec.europa.eu/EnvironmentalFootprint.html.  This data supports the calculations of impact assessment for the categories shown in Figure 13.4.

The methods used to calculate environmental footprint are described in the EC recommendation of of 9^th April 2013 “on the use of common methods to measure and communicate the life cycle environmental performance of products and organisations” – see:
https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32013H0179&from=EN

13.3.3   Content of the LCDN

13.3.3.1    Process data

The LCDN is structured as follows:

• ILCD (entry level) – information about processes and flows with registered data set and registered nodes;
• PEF/OEF – information about processes and flows with a higher level of quality assurance and links to flow data for impact assessment.  The part also contains reference data provided by the EU about the environmental impact of flows for different environmental assessment categories.

ILCD data sets:  There are 2360 of these, mostly provided by the consultancy “thinkstep” (now Sphera - https://sphera.com/) and requiring registration for access.

ILCD nodes:  The nodes with brief comments on their contents are as follows:

PEF/OEF data sets:  none

PEF/OEF nodes:  The nodes with brief comments on their contents are as follows:

Comments on the LCDN content:

1.      The data is sparse.  There are millions of industrial processes carried out within the EU, but only a tiny fraction is documented.  For example, there is only one steel product and there are no nodes supporting processes such as transport or electricity supply.

2.      The structure of the data base is cumbersome, so that if it were greatly extended it would be difficult to find a process of interest.  There are no classification structures for processes that would enable navigation.

3.      The data does not consider processes which have parts in common.  For example, the extraction of aluminium and of copper at the end of life of an electric motor are separate processes with separate flows to and from the environment.

4.      The data does not consider up-stream and down-stream processes.  For example, the production of tinplate has fossil carbon and uranium as input flows, and has carbon dioxide and radioactive waste as output flows.  The amounts depend about the generation mix when the life cycle inventory was calculated.  The data does not enable the effect of a change to the generation mix to be predicted.

13.3.3.2    Environmental footprint reference data

https://eplca.jrc.ec.europa.eu/EF-node/

The data base specifies the contribution of a flow to the following categories of environmental impact:

• Acidification
• Climate change
• Climate change - Biogenic
• Climate change - Fossil
• Climate change- Land use and land use change
• Ecotoxicity, freshwater
• Eutrophication marine
• Eutrophication, freshwater
• Eutrophication, terrestrial
• Human toxicity, cancer
• Human toxicity, non-cancer
• Ionising radiation, human health
• Land use
• Ozone depletion
• particulate Matter
• Photochemical ozone formation - human health
• Resource use, fossils
• Resource use, minerals and metals
• Water use

The climate change data set specifies the Global Warming Potential over a 100 year time period expressed as equivalent kg of CO₂ for flows of different substances to different locations in the atmosphere such as “urban air close to ground”, “lower stratosphere and upper troposphere”, or “non-urban air or from high stacks”.  There are 947 flows for different substances.

As for the process data, the lack of classification structures makes access difficult.  It is not possible to start with a substance and find the different environmental impacts arising from flows of that substance.

13.3.4   Documentation

The ILCD data model has rigorous requirements for the documentation of processes and flows.  This documentation is present in all the data sets within the LCDN.  However the access is by node, and then a flat list of processes within the node in the alphabetical order of their names.

13.3.5   Maintenance and usage

The environmental footprint reference data is dated 2017.  The process data sets are mostly earlier than that.  Both the environmental footprint reference data and the process data sets have “permanent data set URIs” which reference the “LCA infohub” which was withdrawn in 2018.

The level of use is unknown.  The content is so sparse that it seems to be the result of a few pilot projects, rather than a working tool for European industry.

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