Product line design for the automaker under shared mobility: considering dispatching level and carbon emissions

The emergence of the sharing economy has driven the automaker (AM) to expand from traditional vehicle sales into shared mobility service. This paper employs a Stackelberg game framework to examine the impact of dispatching level, specifically its effect on the consumer’s vehicle search time, AM’s product line strategies within the Business-to-Consumer (B2C) car-sharing market. We evaluate three strategies: strategy F (sharing fuel vehicles, FVs), strategy E (sharing new energy vehicles, NEVs), and strategy FE (sharing both FVs and NEVs), with the AM selling both vehicle types across all strategies. Our analysis reveals that strategy FE is not universally optimal, with its effectiveness contingent on dispatching costs. Strategy F proves advantageous under specific cost conditions. Interestingly, NEV sharing does not consistently minimize carbon emissions, nor does FV sharing maximize them, underscoring the complex interplay between dispatching and production costs. Finally, under different cost of the NEV, strategy F achieves the highest social welfare at low to moderate costs due to substantial consumer surplus and AM’s profits, while strategy FE, despite yielding the highest consumer surplus at low costs, results in the lowest social welfare. Conversely, strategy E maximizes social welfare at high costs by minimizing environmental impact. These findings highlight the necessity for AMs to strategically align sharing strategies with market conditions and policy frameworks to balance economic and environmental objectives. Finally, a numerical experiments validates the robustness of our results.