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Life cycle sustainability assessment in the energy sector 123

2.1 Life cycle assessment
Life cycle assessment (LCA) is an environmental sustainability tool that
applies life cycle thinking in order to assess the consequences of human
activities. Broadly speaking, LCA involves:
1. Quantification of environmental burdens of a product, process, or
activity via assessment of the energy and materials used and wastes
released to the environment.
2. Quantification of environmental impacts (i.e., translating the earlier
burdens into potential impacts).
3. Identification of opportunities for environmental improvements along
the life cycle via the identification of “hot spots”.
LCA is standardized via ISO 14040 and 14044 (ISO, 2006a,b), in which four
key phases are identified, as outlined in Fig. 5.3.
LCA is a well-established technique with a wealth of existing literature
demonstrating its use. As the focus of this chapter is on sustainability assess-
ment, rather than LCA, interested readers are directed to other resources for

Fig. 5.3 The four phases of life cycle assessment as defined in ISO 14044.