Material Flow Analysis of Mobility in Switzerand
Cecilia Matasci, Marcel Gauch, Viola Ruehlin, Heinz Böni
Data complexity and volume are often problems when performing a material flow analysis on a bigger scale. The number of studies generating sometimes contradicting data makes that you can easily get lost in details during the process. This is true for example when trying to define the material and energy flows at the country level of a well-studied sector as mobility. Various studies provide data on a particular aspect, but very often they use different methodologies and generate inconsistent results. The challenge results in structuring a big system without getting lost in details. In the frame of this study the whole mobility of Switzerland – defined as the entire vehicle park moving inside the country – has been for the first time extensively assessed using a bottom-up approach and depicted in a simple flow diagram (Sankey). 78 categories of vehicles – from electric and not electric bicycles, cars and buses to airplanes passing through trains and boats -, nine types of materials and two types of energy sources have been characterized. For each of the 78 categories of vehicles different studies and statistics on quantity, material composition, growing/shrinking rate, lifetime, fuel consumption, distance travelled and end-of-life paths have been collected in a matrix. Starting from these different sources a best guest for each factor has been made. This has become the starting point for generating the material and energy flow analysis. The 78 categories have been aggregated into twelve. For each of them the actual stock as well as the ingoing and outgoing flows have been calculated. Additionally, the amount of fuel and electricity necessary to move the vehicles as well as the amount of GHG emitted has been calculated and represented in the same Sankey diagram by depicting the flows in annual ton oil- and CO2-equivalents.