Abstract

This study introduces a cost-effective green hydrogen generation system based on the direct coupling of a discarded photovoltaic module with a proton exchange membrane electrolyzer for domestic natural gas blending (up to 20% v/v). Electrical parameters were identified using an A+A+A+ solar simulator for precise modeling. To mitigate identified impedance mismatches, a physical structural reconfiguration involving the parallel connection of internal substrings was proposed, facilitating stable operation without additional power electronics. This strategy achieved an annual energy extraction yield of 88% relative to an ideal maximum power point tracking-based system. A 30-year sensitivity analysis further demonstrated that this voltage-matching condition remains resilient to long-term parameter drift. Experimental validation under real outdoor conditions confirmed a daily production of 0.345m3, significantly surpassing the 0.12m3 domestic target. The system achieved a daily average Solar-to-Hydrogen efficiency of 7.0%, capturing over 70% of the theoretical maximum. Economic assessment indicated a Levelized Cost of Hydrogen of $5.79/kg, a 18% reduction compared to a benchmark system ($7.05/kg). The results demonstrate that the methodology is fundamentally generalizable to other standard architectures, such as 60 and 96-cell modules. These findings underscore the techno-economic potential of repurposing discarded photovoltaic modules for decentralized hydrogen production, offering a sustainable alternative aligned with circular economy principles.