Technical Assessment of Electric Three-Wheeler Growth, Solar-based Charging and Grid Impacts

The rapid growth of battery-run electric three-wheelers (E3Ws) in Bangladesh creates emerging distribution-grid challenges due to uncontrolled fleet expansion and unmanaged charging practices. In this paper, we propose an integrated framework that couples E3W fleet forecasting, stochastic charging demand, solar-assisted charging, distribution-grid hosting capacity and policy assessment. A weighted logistic model using five published estimates of fleets estimates about 7.3 million E3Ws in 2030. Charging simulations using the Monte Carlo method suggest that uncontrolled charging can lead to an extra peak demand of approximately 5~GW in the evening. Six energy-management scenarios are compared on benchmark feeders based on measured solar-generation data, hosting-capacity, voltage performance, losses, cost, carbon-reduction, and renewable utilization, using linear-programming based scheduling. With the solar-assisted smart charging, the best overall balance is achieved with 77\% renewable charging, 69\% carbon reduction, and improved hosting capacity without battery storage. PV-plus-storage allows for more renewable integration, but is still not competitive at current values. The study also links the quantified technical effects to regulatory shortcomings and suggests an evidence-based roadmap with a focus on fleet registration, managed charging, charger standards, and integration of renewables. The findings show that using coordinated charging strategies can turn fast-growing E3W fleets into flexible distributed energy resources.