Preferences for policy measures to regulate urban vehicle access for climate change mitigation

Urban areas face a significant challenge in decarbonizing transport while maintaining mobility. While Urban Vehicle Access Regulations (UVAR)—such as congestion pricing or low-emission zones—are effective tools for reducing emissions, they are often politically difficult to implement due to public opposition. This study investigates the factors that drive public support for these measures in Budapest, Hungary, a city with a high reliance on public transport but a growing need to reduce passenger car dependency to meet climate goals.

The researchers employed a stated preference survey featuring a choice-based conjoint exercise. Respondents were presented with various policy scenarios—varying by coverage area, enforcement method, access fees, and revenue allocation—and asked to select their preferred designs. This approach allowed the researchers to quantify the relative importance of different policy attributes and identify how preferences vary across different demographic groups.

The study reveals that public support for UVAR is highly sensitive to the design of the policy. Specifically, the cost of access fees and the transparency of revenue earmarking (i.e., how much money is reinvested into sustainable transport infrastructure) are the primary determinants of whether a resident will support a regulation.

Notably, the analysis identified three distinct subgroups of the population with differing preferences, characterized by their age, employment status, and access to private passenger cars. These findings suggest that a "one-size-fits-all" approach to urban vehicle regulation is likely to fail. Instead, policymakers should consider tailoring policy designs to address the specific concerns of these demographic segments. Furthermore, the data suggests that to maximize public acceptance, authorities should consider excluding access fees for non-compliant vehicles or clearly demonstrating the direct benefits of collected revenues.

This research provides a roadmap for urban planners to bridge the gap between environmental policy goals and political feasibility. By understanding that citizens are not a monolith, planners can design more nuanced, targeted regulations that are more likely to gain public support. The study highlights that the "push" measures required for climate mitigation are more palatable when paired with clear, tangible "pull" benefits, such as reinvesting revenue into public transport or cycling infrastructure.