Institutional Sustainability and Low-Emission Vehicle Adoption in Kenya: A Mixed-Methods Case Study of Kiambu County

Purpose: This study examined the association between institutional sustainability and adoption of low-emission vehicles (LEVs) in Kiambu County, Kenya. Methodology: A descriptive mixed-methods study combined stratified random sampling for the questionnaire survey with purposive selection of key informants. Of 218 questionnaires distributed, 196 were completed (89.9%), and 18 interviews were conducted. Institutional sustainability was assessed using eight five-point items (Cronbach’s α = .781). Descriptive statistics and Pearson correlation were combined with thematic analysis of interviews. Findings: The eight institutional sustainability item means averaged 3.57. Institutional sustainability was positively correlated with the perception-based LEV adoption score (r = .641, p < .001). The lowest institutional rating concerned predictable long-term funding (M = 3.39), while interviews highlighted coordination gaps and discontinuous programme financing. The findings indicate association rather than causation; adjusted and interaction effects were not estimated. Unique Contribution to Theory, Practice and Policy: The study applies Institutional Theory to county-level low-emission transport and interprets financing constraints through fiscal decentralisation. It proposes institutional sustainability as a potential moderator of the affordability–adoption relationship for future testing. The findings support clearer implementation mandates, stronger national–county coordination, predictable programme financing and sustained stakeholder engagement.