carbon dioxide absorption; therefore, they select impact categories
quantifying eutrophication and climate change [29, 40]. Studies
dealing with biofuel production select, in addition to climate
change and eutrophication, impact categories related to human
health, eco-toxicity, fossil resources depletion, and cumulative
energy demand [12, 14, 16, 18].
The classification step connects substances emissions to categories where they manifest an impact, e.g., methane emissions to
impact on climate change. This step is performed using characterization models that describe the relation between emissions and
impacts through mathematical functions [34, 41, 42].
The characterization step is the mathematical conversion of a
physical quantity to an indicator score, e.g., kg of methane into kg
of carbon dioxide equivalents. This makes all processes comparable
since they share the same unit of measure. Characterization provides results for midpoint impact categories (Fig. 3), which are
defined as the point where a variety of substances have a common
effect on the environment. For example, climate change is a point
where all greenhouse gases produce an alteration of the radiative
forcing in the atmosphere. The endpoint categories are created by a
further characterization step which results in a broad category
aiming at comparing multiple environmental impacts on a specific
area, e.g., human health. The endpoint characterization is subject
to higher uncertainties and then midpoint and, while providing a
simple result, reduces the clarity of the mechanisms underpinning
the calculation.
There are several available impact assessment methods that a
practitioner can use. The most recent and harmonized indicators
are provided by IPCC for climate change [43], ReCiPe [41], CML
[42], ILCD [39] and Eco-indicator 99 [44]. All of them consider
at least one impact category for the effects on climate change and
eutrophication. ReCiPe provides two categories to differentiate
between marine and freshwater eutrophication, which might be
Fig. 3 Framework of impact assessment based on ILCD methodology [39]
110
Michele Seghetta and Pietro Goglio
quantifying eutrophication and climate change [29, 40]. Studies
dealing with biofuel production select, in addition to climate
change and eutrophication, impact categories related to human
health, eco-toxicity, fossil resources depletion, and cumulative
energy demand [12, 14, 16, 18].
The classification step connects substances emissions to categories where they manifest an impact, e.g., methane emissions to
impact on climate change. This step is performed using characterization models that describe the relation between emissions and
impacts through mathematical functions [34, 41, 42].
The characterization step is the mathematical conversion of a
physical quantity to an indicator score, e.g., kg of methane into kg
of carbon dioxide equivalents. This makes all processes comparable
since they share the same unit of measure. Characterization provides results for midpoint impact categories (Fig. 3), which are
defined as the point where a variety of substances have a common
effect on the environment. For example, climate change is a point
where all greenhouse gases produce an alteration of the radiative
forcing in the atmosphere. The endpoint categories are created by a
further characterization step which results in a broad category
aiming at comparing multiple environmental impacts on a specific
area, e.g., human health. The endpoint characterization is subject
to higher uncertainties and then midpoint and, while providing a
simple result, reduces the clarity of the mechanisms underpinning
the calculation.
There are several available impact assessment methods that a
practitioner can use. The most recent and harmonized indicators
are provided by IPCC for climate change [43], ReCiPe [41], CML
[42], ILCD [39] and Eco-indicator 99 [44]. All of them consider
at least one impact category for the effects on climate change and
eutrophication. ReCiPe provides two categories to differentiate
between marine and freshwater eutrophication, which might be
Fig. 3 Framework of impact assessment based on ILCD methodology [39]
110
Michele Seghetta and Pietro Goglio