ILCD Handbook: Framework and requirements for LCIA models and ...

ILCD Handbook: Framework and requirements for LCIA models and indicators First edition
or lower value resources. This results in the need for additional efforts which can be
translated into higher energy or costs, and thus leads to an increased impact on the
environment and economy (Müller-Wenk, 1998b; Steen, 2006). The endpoint indicator can,
for example, be calculated as ‗willingness to pay‘, expressed as the future payment for
extracting a resource; or the ‗surplus energy‘, expressed as the additional energy
requirement for further extractions of the resource in the future.
Following the impact pathway in Figure 4-15, resource depletion impacts are suggested to
be divided into four categories reflecting the lack of consensus on what is the main issue for
this impact category (see also discussion on the Area of Protection Natural Resources).
Category 1 methods are at the first step of the impact pathway. They use an inherent
property of the material as a basis for characterisation. The environmental relevance is low in
terms of expressing resource depletion, but the characterisation factors are relatively robust.
As described in the AoP for ‗Natural Resources‘, those methods that do not include the
concept of resource scarcity are not considered. Therefore, this category is considered
incompatible with the AoP ‗Natural Resources‘ (irrespective of the quality of the method).
Category 2 methods address the scarcity of the resource by basing the characterisation
factor on the ratio between what is extracted, and what is left. They have a higher
environmental relevance, and potentially a higher uncertainty.
Category 3 methods focus on water and are treated as a separate category due to the
regional dependence of this resource issue, which the characterisation model needs to
consider.
Category 4 describes the endpoint methods. These aim to cover the entire environmental
mechanism.
4.11.1.1 Environmental Mechanism (cause-effect chain)
Figure 4-15 illustrates the cause-effect chain of the impacts due to resource depletion.
4 Requirements for specific impact categories 78