Optimization and sustainability assessment of hybrid PV-powered EV charging and hydrogen refueling systems for low-carbon transport

Abstract The rapid and simultaneous growth of electric vehicles (EVs) and hydrogen vehicles (HVs) has created an urgent need for integrated infrastructure capable of satisfying fundamentally different electricity and hydrogen demands while minimizing reliance on carbon-intensive grid electricity. This challenge is particularly significant in Malaysia, where hydrogen refueling infrastructure remains at an early stage of deployment, and electricity generation continues to rely heavily on fossil fuels. To address this gap, this study proposes a grid-connected photovoltaic (PV)-based integrated energy system for the coordinated supply of EV charging and hydrogen refueling demands in Kuala Lumpur, Malaysia. Representative electrical and hydrogen demand profiles for 100 EVs and 100 HVs were incorporated into a unified HOMER Pro optimization framework. Three system configurations were systematically compared using a structured workflow encompassing load and renewable resource characterization, component sizing and energy flow optimization, techno-economic and environmental assessment, and multi-parameter sensitivity analysis. The results identified the PV-electrolyzer-grid-hydrogen-storage configuration as the best-performing solution, achieving a renewable energy fraction of 88.1%, while delivering a levelized cost of electricity of $0.0516/kWh and a levelized cost of hydrogen of $3.76/kg. Environmentally, the optimized configuration achieved the lowest carbon intensity of 243.4 gCO₂/kWh and reduced the cost-normalized energy-equivalent CO₂ indicator by 45.98% relative to the grid-only configuration. These findings demonstrate that coordinated PV-supported EV charging and hydrogen refueling can provide a technically viable and economically competitive pathway for reducing grid dependence, lowering transport energy emissions, and supporting the transition toward an integrated low-carbon mobility infrastructure in Malaysia.