Techno-economic assessment of renewable-based EV charging stations with green hydrogen production for excess power management under different consumption patterns

Abstract

Regions with strong renewable potential and low-to-moderate grid tariffs, provide cost-effective power solutions for electric vehicle (EV) charging stations. The mismatch between demand and renewable generation profiles, along with the difficulties in handling surplus electricity in systems with high renewable penetration, poses a challenge to optimizing the cost of energy (COE). To overcome these challenges, various consumption patterns (CPs) were optimized using a dispatch strategy aimed at minimizing costs and utilizing excess renewable power for green hydrogen production. This approach was designed to achieve net-zero power exchange for excess power management by ensuring that the electricity supplied from the grid to the electrolyzer is equal to the surplus power fed back into the grid. Results show that, in standard charging stations, the COE ranges from $0.042–$0.061/kWh for mid-day residential and commercial-office CPs, achieving a renewable contribution of over 60%. The COE ranges from $0.058–$0.067/kWh for highway and public transportation fast chargers, with a renewable contribution exceeding 45%. The green hydrogen production approach led to an approximately 20% COE increase, reducing excess power from over 30% to less than 5%. With a hydrogen production cost of $3.1–$7.2/kg, the model highlights the potential affordability of integrating EV and hydrogen-fueled vehicle stations.