Life Cycle Assessment (LCA) of Composite: limitations on decision making for composite environmental sustainability

Life Cycle Assessment (LCA) is a systems approach to understanding the environmental impacts of a product or process. It is guided by the ISO14040 series of standards. The expectation is that there will be a clear goal and scope for the study with well-defined system boundaries. It is essential to define a Functional Unit (FU) which sensibly allows comparisons between differing configurations of the same product. The assessment should ensure that there is conservation of mass and energy flows. However, a number of shortfalls have been identified in LCA reports. For example, the standard environmental inventory data bases may not contain data specific to the materials used, or that data may not be fully compliant with the conditions being modelled. The literature contains incomplete studies with e.g. epoxy resin but no hardener, or fabrics with no consideration of textile process such as weaving. Given the cautionary tales, any LCA should be regarded as unfinished unless signed off by an LCA practitioner or Chartered Environmentalist? LCA can be good for identifying hotspots in the system but do be wary of comparisons of similar systems where data uncertainty could suggest incorrect ranking of the studied systems.