In response to the imperative of climate change mitigation, the European Union has devised a strategy to achieve climate neutrality by 2050. Extensive research has focused on CO2 life cycle analysis of propulsion systems. However, achieving net-zero CO2 emissions necessitates adjusting the development key performance indicators. Consequently, we investigated the sustainability impacts of various propulsion concepts integrated in a C-segment SUV, assuming a 100% renewable energy scenario. The propulsion concepts studied include a hydrogen-fueled 48 V mild hybrid, a hydrogen-fueled 48 V hybrid, a methanol-fueled 400 V hybrid, a methanol-to-gasoline-fueled 400 V plug-in hybrid, an 800 V battery electric vehicle (BEV), and a hydrogen fuel cell electric vehicle (FCEV). To facilitate a thorough and unbiased comparison of these concepts meeting predetermined customer requirements for system design, we conducted an integrated and prospective Life-Cycle Assessment (LCA) utilizing the methodology of DIN EN ISO 14040/44 and the Product Environmental Footprint. Additionally, the socio-economic impact of these concepts was evaluated, considering the total cost of ownership for a private end-user. Diverging from conventional approaches, we adopted an integrated approach to aggregate the Life-Cycle Inventory data, combining (simulation) model-based system design and LCA databases. In the context of the defossilized energy scenario, this results in increased system sustainability, regardless of the propulsion concept. While the FCEV showed slight advantages among these propulsion concepts, the BEV revealed shortcomings that could be mitigated by adapting requirements or battery technology. Our findings advocate for open-minded development of propulsion concepts tailored to specific use-cases and targeted requirements, emphasizing the necessity of considering the entire life cycle.