count the absolute mass which can be reduced in one vehicle and the total number of vehicles. On the one hand a heavy vehicle like a passenger train has a higher potential for an absolute weight reduction compared to a light vehicle like a passenger car. A general weight reduction of all passenger cars, on the other hand, results in a high total weight reduction due to the great numbers of cars.
To quantify these effects we analyse a scenario for Germany and calculate the life- time energy and CO2 emission savings for an assumed 10 % weight reduction of all new registrations of the year 2000. It has to be mentioned that these energy and CO2 savings will be realised during a longer period of time, determined by the life-time of the vehicles. Please note that this study does not deal with the technical realisation and market feasibility of a 10 % weight reduction.
The scenario takes into account that the vehicles described in the preceding sections have a different share of the total primary energy use and CO2 emissions, due to different shares of the transport performance. The calculation shows the significance of the reduction potential for the different vehicle categories.
Today’s passenger and freight transport in Germany is dominated by road vehicles. Rail transport accounts for only 6 % of the primary energy consumption of road vehicles (Chart 13). Road vehicles are dominated by passenger cars with 63 % and heavy duty vehicles with 29 % of the primary energy consumption. City and Long distance buses account only for about 1 % of the primary energy consumption each. The differ- ent shares of primary energy consumption also point out the different uses and per- formances of the vehicles which signifies a different potential for weight induced energy and emission savings.