Demand-Coupled Assessment of Rooftop Solar PV Integration for Dhaka MRT Line-6

Rapid urbanization and limited land availability increase the importance of utilizing existing transport infrastructure for renewable-energy deployment. The previous study has determined the technical feasibility of integrating PV (Photovoltaic) along Dhaka MRT Line-6, however, the estimated PV generation and real electricity demand of MRT needs to be better interpreted. This research proposes a PVsyst based station-group framework for the Uttara North-Motijheel corridor comprising 16 stations and correlates rooftop PV generation with the traction and auxiliary electric powers needed for battery-free grid-connected operation. Three representative station archetypes are modeled and scaled throughout the corridor, leading to an installed capacity of approximately 15.79~MWp and an average PV generation of 62.71~MWh/day, or approximately 22.89~GWh/year. The base case traction-energy requirement is estimated to be 54.87~MWh/day, yielding an overall PV-to-traction energy ratio of 114.3\%. This is not to say that this is a real-time solar penetration figure, as there would be a need for further grid balancing due to mismatch in PV generation and MRT demand, as well as auxiliary loads. If one assumes a total electricity demand of the houses in the MRT, the PV generation estimated in this study amounts to about 60-65\% of the annual electricity consumption of the rooftops. The study thus shows that the PV potential at the corridor scale should be assessed not only in terms of annual PV generation but also in relation to the full MRT load boundary and grid connected operating conditions.