A Photovoltaic-Assisted Seawater Electrolysis (PV-E) Reactor is an integrated system designed to convert solar energy directly into green hydrogen using seawater as the primary feedstock. The design of these reactors focuses on the "Direct vs. Indirect" coupling of solar power and the stabilization of catalysts under the intermittent energy loads characteristic of PV arrays.

In modern seawater electrolysis, the reactor is typically classified by how it interacts with the solar source and the saline environment. (1) Modular Indirect Coupling (Industry Standard): This configuration separates the PV field from the electrolyzer, using a DC-DC converter with Maximum Power Point Tracking (MPPT). The indirect coupling achieves ~35–40% higher hydrogen yields compared to direct connection because it forces the PV modules to operate at their peak efficiency regardless of solar irradiance. (2) Resilience: Modern power electronics (HMI/PLC controlled) manage the "start-stop" cycles that occur during cloud cover, preventing the rapid catalyst degradation caused by potential fluctuations. (3) Integrated Solar Vapor Electrolyzers (ISVE): Solar-thermal energy is used to generate high-flux purified vapor at a photothermal interface. This vapor is then electrolyzed in a separate zone. By using vapor as the reactant, the reactor naturally excludes salts, preventing Cl- corrosion and Ca/Mg scaling entirely. These systems have demonstrated 15.2% Solar-to-Hydrogen (STH) efficiency and over 1,400 hours of stable operation.

References:

H. Nishiyama, et. al. Photocatalytic solar hydrogen production from water on a 100-m2 scale, Nature, 2021, 598, 304–307

V. Andrei, et. al. Solar Panel Technologies for Light-to-Chemical Conversion. Acc. Chem. Res. 2022, 55, 23, 3376–3386