[leonidasrup]

Coupling PV to electrolyzers and efficient hydrogen production using solar energy is still open research problem. Batteries will be probably needed.

"The low efficiency of PV-electrolyzer systems can be attributed to several factors: intrinsic losses in both the PV and electrolyzer units, energy consumption by balance-of-system components (e.g., inverters, thermal management), and, most critically, ineffective electrical coupling. Although some researchers advocate for direct coupling as a cost-effective solution, variable solar input remains a major challenge. Fluctuations in solar irradiance can cause the power delivered to fall outside the acceptable operating range of electrolyzers, leading to frequent shut-downs and start-ups. These cycling events can accelerate degradation, particularly in PEM electrolyzers, and also affect the purity and yield of hydrogen"

"Recent studies also highlight the integration of battery energy storage systems (BESS) into large-scale PV-CSP hybrid plants as a strategic enhancement. With anticipated declines in battery costs, this integrated approach may become increasingly viable in the near future."

https://link.springer.com/article/10.1007/s44373-025-00080-4