Method for a Multi-Vehicle, Simulation-Based Life Cycle Assessment and Application to Berlin’s Motorized Individual Transport

Abstract

The transport sector in Germany causes one-quarter of energy-related greenhouse gas emissions. One potential solution to reduce these emissions is the use of battery electric vehicles. Although a number of life cycle assessments have been conducted for these vehicles, the influence of a transport system-wide transition has not been addressed sufficiently. Therefore, we developed a method which combines life cycle assessment with an agent-based transport simulation and synthetic electric-, diesel- and gasoline-powered vehicle models. We use a transport simulation to obtain the number of vehicles, their lifetime mileage and road-specific consumption. Subsequently, we analyze the product systems’ vehicle production, use phase and end-of-life. The results are scaled depending on the covered distance, the vehicle weight and the consumption for the whole life cycle. The results indicate that the sole transition of drive trains is insufficient to significantly lower the greenhouse gas emissions. However, sensitivity analyses demonstrate that there is a considerable potential to reduce greenhouse gas emissions with higher shares of renewable energies, a different vehicle distribution and a higher lifetime mileage. The method facilitates the assessment of the ecological impacts of complete car-based transportation in urban agglomerations and is able to analyze different transport sectors.

Environmental Impact of Subsidy Concepts to Stimulate Car Sales in Germany

“…During the use phase, the replacement of vehicle spare parts and the maintenance of the road network is considered. To calculate the vehicle maintenance the flow passenger car maintenance is used in Ecoinvent and is adapted according to the vehicle's weight and power train type [50]. We follow the same approach as in Agora 2019b [51] "basic scenario" and assume for each vehicle a lifespan of 150 000 km and do not consider any battery exchange for BEVs and PHEVs.…”

Integrated Approach for the Assessment of Strategies for the Decarbonization of Urban Traffic

“…Other studies like [58] include several impact categories to evaluate the environmental impact, but neglect the production and end of life phase of the considered products. A more detailed description of LCAs in the field of vehicles and urban transport is presented in [59]. Along with changes in drive train technology and transportation strategies, implications for social and economic sustainability arise.…”

“…In order to compare the effects of such changes in the transport system with each other and with the status quo, a holistic assessment of emissions over the life cycle is necessary. The tool presented here (depicted in Figure 4) combines LCAs and the MATSim scenarios within one framework to derive results for vehicles with different drive train options and varying operation strategies [59]. The WTW GHG emissions are then calculated ex-post by multiplying the observed kilometers driven by a vehicle as result of the transport simulation with its vehicle type specific energy consumption and the corresponding emissions factor per energy unit.…”

“…However, one vehicle does not represent the variety of vehicle segments in private transportation. Therefore, we defined three vehicle classes (small, medium, large) and parameterized respective dummies (compare [59]). For other transport segments (e.g., freight traffic), different vehicle types are already available in the traffic simulation and chosen by the tour planning algorithm depending on their cost effectiveness.…”

“…Impact Assessment: We assess several impact categories (for example the global warming potential) analogous to current studies [57,107,108]. Especially for the single vehicle LCAs, the results serve as validation against other studies [59].…”