Page 48 - Materials Chemistry, Second Edition

Life cycle assessment as decision support: a systemic critique

assess and recommend ways to improve the environmental performance of the product or 35
system. Alternatively, the LCA may be used as information by consumers seeking to evaluate
alternative ways to gain the service provided by the product or system. Reports in consumer
and general media of LCAs on different nappies are an example of this type of information
that consumers – parents, in the case of nappies – use to make product choices (e.g. Aumoˆnier
and Collins 2005).
A great strength of LCA is that it provides definite quantifiable results, and where it reveals
linear causes of impacts, it can also reveal exactly the points where change is required to ‘fix’
them. As such, it provides a direct conduit to decisions and taking action: it tells us ‘what to do
on Monday’ (Kelly 2006). However, an open question remains as to whether LCA is adequate
to meet the complexity of environmental issues across all cases. Does it provide solutions to
systemic problems where the causes and effects are not linear but iterative, interconnected,
uncertain and even, possibly, boundless?

4.3 Problem definition in LCA
LCA implicitly recognises that problems under analysis exist in systems. This is clear from the
way LCA is used to define system boundaries and systems dynamics such as average or marginal
supply, system displacement effects, and the interactions between the natural and technologi-
cal systems involved in the analysis.
However, there is a constraint in the way LCA is often applied that potentially reduces it to
a mechanistic tool, restricted to calculating the impacts of simple, isolated problems. In these
cases, the initial question that the LCA is designed to evaluate is already defined and isolated
by a producer, client or consumer before the LCA commences. This is an obvious corollary of
the LCA proponent’s interest in his or her own particular identified ‘problem’. However, as
stated above, a narrowly defined problem or question leads to a correspondingly narrow set of
results. Hence, a narrowly set question in LCA can lead to narrow, mechanistic and sometimes
inappropriate conclusions.
For example, in an LCA conducted in Melbourne in 2003 (Boyapati 2003 et al. cited by
Public Transport Users Association), the objective was to investigate options for reducing green-
house gas emissions of urban transport. The LCA was conducted around a relatively narrow
definition of the problem: the emissions of commuter vehicles. The greenhouse gas emissions of
trams were compared with those of cars and buses, and the LCA’s results purported to show that
a tram produces more emissions than a car, per passenger kilometre. The LCA practitioners
accordingly recommended that cars were a better option than trams for reducing greenhouse
gas emissions. If this recommendation had led to trams being phased out in favour of cars, it
would have significantly increased greenhouse gas emissions overall. The LCA apparently did
not take into account the embodied energy in Melbourne’s existing extensive tram infrastruc-
ture together with rolling stock, or that this would have to be demolished and replaced with
road infrastructure and new cars to accommodate a change in policy that favoured cars, or any
trend to increase private car usage which may attend an increase in road infrastructure. The
LCA may have provided results for the given question in simple terms, but did not recognise or
consider the context of the problem – that is, the urban fabric of Melbourne.
Assessments of biofuels as an answer to energy scarcity and greenhouse gas emissions asso-
ciated with fossil fuels may also founder for similar reasons. If these assessments are limited to
the question of how to supply alternative energy sources to fossil fuels, their recommendations
may actually create new environmental pressures. A significant increase in biofuels produc-
tion may lead, for example, to such competition for land use that food crops are held back in
favour of fuel crops, resulting in increased food scarcity (Beer et al. 2002). The extent to which

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