Feasibility Limits in Corridor-Wide EV Fast-Charging Station Planning for Sustainable Transport Electrification: An MILP Study of Puerto Rico’s PR-2

Planning fast-charging infrastructure for electric vehicles (EVs) supports sustainable transport electrification. This study identifies when a corridor-wide plan along Puerto Rico Highway 2 (PR-2) becomes infeasible and which modeled constraint limits it first. A mixed-integer linear programming (MILP) model with 229 candidate sites across 27 municipalities, integer 150 kW port decisions, a 3 MW per-site ceiling, corridor coverage, and a shared upstream-capacity screen is solved for a February 2024 baseline and six electrification scenarios under an upper-bound demand assumption. The baseline is feasible with 30 stations, 178 ports, and 26.7 MW, whereas all six future scenarios are infeasible. San Juan and Guaynabo, which hold one-third of the island’s registered EV stock but four candidate sites each, exhaust their candidate-set capacity first, at closed-form thresholds of 1.78% and 3.38% electrification, versus 8.99% in the calibrated-2030 case. This threshold reproduces the MILP shortfall to four decimal places in all six infeasible scenarios. At a screening fraction of 0.20, removing the upstream screen changes neither feasibility nor shortfall. Restoring 2030 feasibility would require at least 21 and 11 represented 3 MW sites, versus four each. Under the modeled assumptions, these findings support examining candidate-site limitations before upstream grid reinforcement in sustainable corridor planning.