Techno-Economic and Environmental Analysis of an Optimized Hydrogen Refueling Station Integration in a Renewable Energy Microgrid †

Fuel cell electric vehicles represent a promising option for reducing greenhouse gas emissions from heavy-duty transport. In this context, integrating Hydrogen Refueling Stations (HRSs) into renewable-based microgrids represents a key strategy for ensuring sustainable hydrogen production. This study investigates the integration of an HRS into a photovoltaic-based microgrid supplying a fleet of 21 urban buses. A detailed hourly model of the photovoltaic system, battery storage, hydrogen generator, hydrogen storage, compression and refueling processes was developed. A multi-objective optimization was performed to minimize the Levelized Cost of Hydrogen (LCOH) while maximizing the Self-Sufficiency Rate (SSR). Three Energy Management Strategies (EMSs) were compared: hydrogen production using only renewable electricity, mixed renewable and grid electricity and grid-only electricity. Results reveal a marked economic penalty associated with achieving full self-sufficiency. Under the renewable-only EMS, the LCOH increases from 16.8 €/kg at an SSR of about 80% for the minimum-LCOH solution to 24.3 €/kg at an SSR of 100%. Under the MIXED-EMS, it increases from 12.3 €/kg at an SSR of about 47% to 22.7 €/kg at an SSR of 100%. When revenues from surplus electricity export are included, the corresponding LCOH values at 100% SSR decrease to approximately 15 €/kg, regardless of the EMS adopted. Compared with the emissions from the diesel-bus fleet, hydrogen buses could reduce emissions by about 12% with grid-based production and up to 99% with renewable hydrogen.