A ¼ product system matrix, describing product flows between
unit processes (n n)
B ¼ unit emission matrix, describing emissions and resource use
over m categories (m n)
C ¼ characterization matrix, describing impacts to k categories
per emission or resource use (k m)
h ¼ life cycle environmental impacts of functional unit f (k 1).
Typically the product system matrix A is subdivided into foreground and background processes, where the foreground system includes the processes modeled in the case study and the background is obtained from literature and databases. In this case study,distances between the electrodes in each capacitor layer, and consequently a higher power supply for the same size of capacitor (Takala et al., 2010). This allows a smaller amount of capacitors in a capacitor bank to provide the same services as a larger amount with conventional dielectric materials. Based on prestudies, an 18% reduction in the number of capacitors needed to supply the specified reactive power was assumed (Takala et al., 2010). The reduced
material needs influence the whole life cycle from raw materials supply to manufacturing, transport and waste recycling.