Page 88 - Materials Chemistry, Second Edition

4.4 LCSA development in two decades of practice: A case study anthology 83
social impacts from year to year. The assessment was performed from “cradle-to-grave” for a
functional unit of 1MWh of electricity generated. Five environmental issues comprising of
11 indicators, and 4 socioeconomic issues comprising of 5 indicators were assessed. In
assessing the environmental impacts (LCA), the SimaPro 8.0 software was used. Background
data were obtained from Ecoinvent v3.0 database. They collected foreground data from
sources directly related to systems operating in Portugal as of 2016. It was assumed that
the system characteristics and conditions were constant throughout the plant lifetime. Envi-
ronmental impacts were assessed using ReCiPe impact assessment method implementing a
hierarchist (where priority is given to the environmental dimension) midpoint approach. For
toxicity-related indicators and freshwater scarcity footprint, Usetox 1.04 and AWARE
methods were used, respectively. The overall sustainability performance was obtained by
ranking each generation system based on un-weighted color gradient scale for each indicator.
The results of the overall sustainability performance are shown in Fig. 4.15.
Their study revealed that renewable systems were more sustainable than fossil fuel-based
systems. In particular, small hydro systems were found to be most sustainable whilst coal
systems were the least sustainable.

FIG. 4.15 Overall sustainability performance of different electricity generation systems in Portugal (Kabayo
et al., 2019).