Performance Evaluation of a Solar-Powered Portable Alkaline Electrolyzer for Hydrogen Production

This study provides the inaugural comprehensive assessment of an ultra-low current density (۳ mA/cm²) portable alkaline electrolyzer utilizing uncoated SS۳۱۶L electrodes, illustrating the essential trade-offs among simplicity, cost (<۸۰۰), and efficiency in off-grid hydrogen production. The system has an energy efficiency of ۹.۶%, which shows that it loses voltage in three ways, ۴۵% from the oxygen evolution reaction (OER) kinetics on bare steel, ۲۵% from ۲ mm electrode gaps, and ۲۰% from room-temperature operation. The device runs on ۱۳ V and ۷.۸ A (۱۰۱ W) from a solar panel and produces hydrogen at a rate of ۰.۰۵۴ L/min (STP) with an energy cost of ۳۵۰ kWh/kg H₂. Three experimental runs verified repeatability with a ۵% margin of error. Dynamic testing with different power inputs (۵۰ to ۱۰۰ W) kept Faradaic efficiency above ۹۵%, which showed that the system was compatible with solar energy. Quantitative loss investigation using electrochemical impedance spectroscopy found that OER overpotential (۰.۴۵ V) and ohmic losses (۰.۳۵ V) were the main problems. The results present benchmarked performance metrics for low-cost, portable green hydrogen systems and clarify how to improve performance, zero-gap architecture could lower cell voltage by ۰.۳ V, and NiFe catalyst coatings could reduce OER overpotential by ۰.۲ V, which could increase overall efficiency to about ۲۰%.

کلیدواژه ها:

Alkaline water electrolysis ، Faradaic efficiency ، Hydrogen production ، Renewable Energy System ، Portable electrolyzer ، electrochemical impedance spectroscopy