Need for Speed – A Systems Perspective on the Environmental Cost of High Top Speeds in German Passenger Cars

• Main Author: Chordia, Mudit
• Format: Others
• Language: English
• Published: KTH, Hållbar utveckling, miljövetenskap och teknik 2018
• Subjects: Lifecycle assessment; Private cars; Down-engineering; Engineering and Technology; Teknik och teknologier
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-234232

Automobiles have evolved from meeting transportation needs of their owners a century ago, to addressing transportation desires of their owners today. They now meet the owner’s desire for status though sign values such as speed, safety, environmental consciousness, sexual desire, freedom, masculinity etc., and are anthropomorphised by creatively invented names. It comes as little surprise that the transport sector alone accounts for nearly a quarter of the global greenhouse gas (GHG) emissions – levels that are further expected to double by 2050. Germany, which is the highest emitter of GHGs in Europe recorded nearly 1 Gt GHG emissions in 2016 alone. Such high concentration of emissions from the German transport sector can in some part be attributed to the autobahn network in Germany – 2/3rd of which have no mandated speed limits, thus encouraging the car manufacturers to design cars that are operation worthy even at speeds of up to 250 km/ h (or higher), that are unrepresentative of real world driving conditions. This thesis aims at quantifying the environmental impact of this design for high top speeds in passenger cars from a systems perspective. This is achieved by using a comparative lifecycle assessment of passenger cars from a cradle-to-grave approach. A number of passenger car specifications are modelled which include a representative base case for a German car, vehicle light-weighting approach through material substitution, and down engineered car. The results of the comparative lifecycle assessment showed that, light-weighting a passenger car through material substitution showed a reduction of between 3 to 9% in impact categories such climate change, particulate matter formation, fossil depletion, human toxicity and terrestrial eco-toxicity as compared to the baseline levels. Higher reductions of nearly 12% and 31%, were observed in the marine eco-toxicity and the metal depletion impact categories respectively. However, there exists potential to reduce up to 40% in all selected environmental impact categories when comparing baseline passenger car to a down engineered one. Further, light-weighting a passenger car through higher material substitution showed an increase in the indirect energy consumption and higher impacts in ten out of the eighteen impact categories, as compared to a lower material substitution option. Thus, an important conclusion drawn from this thesis is that when implementing steps to reduce environmental impacts of passenger cars, shift of burden must be avoided between the lifecycle phases as well as the impact categories.