[ solar coupling ]
Conclusions
In summary, off-grid solar hydrogen systems face performance losses primarily due to limitations from power electronics and electrolyzer operating constraints. Peak-power shaving and threshold losses can significantly reduce the usable solar energy, particularly in conventional systems with centralized stacks and inverters. These effects are compounded in regions with lower irradiance, where threshold losses dominate.
The use of power electronics not only introduces conversion inefficiencies and curtailment losses but also increases capital and operational costs. In contrast, a highly modular electrolyzer architecture, as presented in method 3 by XINTC, mitigates these losses by enabling direct coupling to the solar field, eliminating inverters, and maintaining operation near the maximum power point through dynamic modular control. This approach significantly reduces both curtailment and threshold losses, offering a more efficient solution for decentralized green hydrogen production at any location.
References
¹ IEA.( n. d.). Share of renewable electricity generation by technology, 2000 – 2030. ² Lazard.( 2020, October). Lazard’ s levelized cost of energy analysis – version 14.0. ³ Wirth, H.( 2021, March 11). Recent facts about photovoltaics in Germany. Fraunhofer ISE.
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DNV.( 2023, October). Energy Transition Outlook
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HYFINITY.( 2024, October 16). Webinar presentation at Mission Hydrogen [ Webinar ]. Mission Hydrogen.
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XINTC.( 2025). XINTC official website.
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Alencon Systems.( n. d.). DC overbuilds for solar: What they are and how they work.
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International Journal of Hydrogen Energy, 42( 15)( 2017), 9406 – 9418.
9
International Journal of Hydrogen Energy, 48( 88)( 2023), 34210 – 34228.
10
Journal of The Electrochemical Society, 170( 6)( 2023), 064510.
¹¹ Photovoltaic Geographical Information System( PVGIS), European Commission, Joint Research Centre.
¹² PVWatts Version 5 Manual, A. P. Dobos, National Renewable Energy Laboratory( NREL), 2014.
About the author
Ahmadreza Rahbari is Director of R & D at XINTC, where he leads innovation in scalable electrolysis solutions and drives market-oriented development in green hydrogen production. With a PhD in Mechanical Engineering and a background in molecular simulations, he has directed numerous research efforts across the hydrogen value chain. As a technical leader, he integrates system-level modeling with cross-sector collaboration to advance sustainable technologies.
About XINTC
XINTC is advancing hydrogen technology by manufacturing and marketing highly modular, scalable Advanced Alkaline Electrolyzers( AAEs) ranging from 150 kW to over 100 MW. Designed for flexibility and efficiency, XINTC’ s AAEs deliver hydrogen at variable pressures from 1 to 13 bar with high purity, making them suitable for diverse applications in mobility, industry, and the built environment. XINTC’ s AAE systems are optimized for dynamic operation, allowing direct coupling with renewable energy sources such as solar PV and wind power. The system architecture is based on a modular, standardized design, enabling rapid scalability while eliminating time-consuming EPC processes. Each gas module pair integrates smart control software and embedded electronics, ensuring high efficiency, low operating costs, and operational safety. With an expandable design in 150 kW increments, XINTC’ s solutions provide a future-proof approach to green hydrogen production for the world’ s middle market, supporting the global transition toward clean and sustainable energy.
20 Hydrogen Tech World | Issue 22 | June 2025