New probabilistic multi-criteria model for assessing the integral sustainability of private cars with different propulsion systems

Assessing the overall sustainability of private vehicles remains a methodological challenge, as existing approaches often fail to integrate the economic, social, and environmental pillars of the triple bottom line framework in a balanced and comprehensive manner. Although numerous studies address specific dimensions — particularly the environmental one — there is still no widely applicable method capable of delivering a robust global sustainability assessment across diverse vehicle technologies and contexts. This study proposes a probabilistic model for evaluating the overall sustainability of private cars at a global level. The model builds on the MIVES–Monte Carlo method and incorporates an extensive set of economic, social, and environmental indicators. Their definition and assessment procedures were established through a structured Delphi process, complemented by insights from the literature. The environmental dimension is evaluated through four sub-models: one with a well-to-wheel+ scope and three adopting a cradle-to-grave perspective. The model is applied to two case studies. The first demonstrates its usefulness in assessing the overall sustainability of current commercial vehicles with different propulsion systems. The second uses Monte Carlo simulation to estimate sustainability levels for hybrid electric (HEV), plug in hybrid (PHEV), battery electric (EV), and conventional petrol and diesel vehicles. The results reveal that overall sustainability rankings depend strongly on the environmental sub-model selected: three sub-models favour EVs, whereas one reverses the ranking, placing conventional vehicles first. Differences narrow when broader environmental indicator sets are used, although all technologies present substantial room for improvement. These findings highlight the need for policymakers to promote robust environmental assessment standards and to support technological improvements that enhance overall sustainability. • The model serves to assess the integral sustainability of private cars. • The model allows partial comparisons at economic, social, and environmental levels. • The conventional vehicle can surpass the electric one in terms of sustainability. • Different environmental scopes lead to opposing rankings. • It is necessary to promote new cradle-to-grave environmental standards and databases.