Human Settlements Review - Parliamentary Monitoring Group

Human Settlements Review, Volume 1, Number 1, 2010
at our impact on bio-diversity (Cole, 2000: 949-
957). With this methodology environmental
impacts tend to be identified, mostly using
methods such as checklists, matrices and
evaluations, logical frameworks, cost-benefit
analysis and multi-criteria assessments
(Adinyira et al., 2007: 3). On the basis of this
methodology, many sustainability assessment
techniques have been developed that focus
on energy and material flow and address both
resources use and wastes, arising across a
wide range of development activities.
In general, environmental methodologies have
significant limitations with respect to the range
of sustainability issues they are capable of
addressing. The methods are mostly limited
to environmental issues of sustainability
and to applications at the levels of policy
planning, programme development and urban
design. These fall short of technical, social
and economic issues that this paper aims to
address.
4.6.2 Life cycle assessment
Life cycle assessment (LCA) methodologies
are aimed at incorporating the four key elements
of sustainability including environmental,
intergenerational equity concerns and the
need for a multidisciplinary and holistic
approach in the development and decision
making processes (Adinyira et al., 2007: 4).
LCA is based on a structured methodology
that can be utilised, for example, to evaluate
environmental implications of products,
processes, projects, or services throughout
their life cycles from raw materials extraction
to end of life (Sahely et al., 2005: 74). Its origin
is traced to Agenda 21’s call for the integration
of the environmental aspects and other key
elements of sustainable development, as
envisaged in the definition put forward by
WCED (Adinyira et al., 2007: 4).
Life Cycle Analysis (LCA) has four components,
namely goal and scope definition, inventory
analysis, impact analysis, and improvement
analysis (Sahely et al., 2005: 74). Goal
and scope definition requires defining the
purpose and boundaries and establishing
the functionality unit of the system to be
considered. The inventory analysis is mainly
an accounting of energy and raw materials
usage and discharges to all media over the
entire life cycle of the system (i.e. product,
material, process, project, or service). In
practice, the impact analysis component of
LCA lists the results from inventory analysis
in various environmental impacts categories,
such as depletion of resources and global
warming potential. Lastly, improvement
analysis is a systematic evaluation of the
needs and opportunities to reduce the
environmental burden associated with the life
cycle of the system. While LCA focuses mainly
on environmental impacts, life-cycle costing
(LCC) has emerged as an equivalent tool for
examining the economic impacts of a system
(Sahely et al., 2005: 75).
The main advantage of LCA is that it is a
well-established, standardised methodology,
where potential impacts are aggregated and
quantified and it is system or project specific.
However, LCA also has some major drawbacks,
including the complex and time consuming
nature of the analysis, large data requirements
and boundary definition. Furthermore, LCA
is mainly limited to environmental aspects
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