Photovoltaic–Electrolyzer System Operated at >50 mA cm−2 by Combining Large‐Area Shingled Silicon Photovoltaic Module with High Surface Area Nickel Electrodes for Low‐Cost Green H2 Generation

Green hydrogen plays an important role in the energy transition as a renewable energy vector for long‐duration energy storage and as feedstock chemical for the industry. To reduce the price below 1.5 € kg −1 H 2 , competitive to production from fossil fuels, silicon photovoltaic (PV)‐powered efficient anion‐exchange membrane (AEM) water electrolysis is a promising combination. Practical implementation of such a photovoltaic–electrolyzer (PV–EC) technology requires standard area‐sized solar cells and electrolyzers operating at large current densities. Nonetheless, state‐of‐the‐art research often employs <10 cm 2 PV devices and electrolyzers operated at <10 mA cm −2 . Herein, a commercially relevant PV–EC system combining shingled standard silicon technology with efficient low‐cost AEM electrolysis using high‐surface‐area (26 m 2 cm −3 ) nickel nanomesh electrodes is presented. The produced H 2 , operating current, and voltage are in situ monitored over >20 h yielding a stable solar‐to‐hydrogen efficiency ( η STH ) of 10% at electrolyzer current densities ≈60 mA cm −2 and dynamic load testing up to 300 mA cm −2 results in stable performance. Based on the measured PV–EC system data, best practices to accurately determine the η STH for PV‐powered water‐splitting devices and the validation of this benchmark against important component parameters for practical implementation of this technology are discussed.