SunHydrogen modules exceed 10% solar-to-hydrogen efficiency in pilot push

SunHydrogen has reported solar-to-hydrogen efficiency above 10% for its photoelectrochemical and integrated photovoltaic-electrolysis modules following testing at the laboratories of Sparc Hydrogen in South Australia, paving the way for further development at pilot scale.

The US-based hydrogen technology company said its modules also produced more hydrogen as sunlight was concentrated during the testing, a result that could support their integration into Sparc Hydrogen’s concentrated-sunlight reactor technology.

Solar-to-hydrogen efficiency measures the proportion of solar energy converted into hydrogen. SunHydrogen said achieving an efficiency above 10% represents an important milestone for technologies designed to produce hydrogen directly from sunlight and water.

The companies have entered into a 24-month Technology Collaboration and Intellectual Property Protection Agreement to investigate whether SunHydrogen’s modules can be integrated into Sparc Hydrogen’s reactors to reduce the cost of renewable hydrogen production.

The collaboration will initially involve laboratory testing at increasing levels of solar concentration. Subject to the achievement of agreed milestones, the programme will progress to outdoor testing at Sparc Hydrogen’s SHARP pilot facility at Roseworthy in South Australia.

Results from the testing will subsequently be used in a jointly funded techno-economic assessment examining the levelised cost of hydrogen, which measures the total cost of producing a kilogram of hydrogen over the lifetime of a production system.

The programme will be divided into multiple stages, with independent reviews and go-or-no-go decisions before each phase. A joint steering committee will oversee the collaboration, while each company will retain ownership of the technology and improvements it contributes.

Under the agreement, Sparc Hydrogen will have rights during the collaboration to use SunHydrogen’s technology in concentrated-light applications above an agreed concentration level, reflecting Sparc Hydrogen’s focus on concentrated solar hydrogen production.

SunHydrogen will retain rights to its core market of decentralised hydrogen production using natural, unconcentrated sunlight. Sparc Hydrogen has also acknowledged that it is not developing its own photocatalyst or photoelectrochemical materials and is not pursuing single-sun water splitting technology in SunHydrogen’s field.

If the collaboration is successfully completed, Sparc Hydrogen will have an 18-month option to negotiate either a long-term supply agreement or a manufacturing licence for SunHydrogen’s modules for use in its reactors. The agreement also provides Sparc Hydrogen with a right of first offer over competing arrangements in the same field during the option period.

Sparc Hydrogen is a joint venture involving Sparc Technologies, Fortescue and the University of Adelaide. Its concentrated-light photocatalytic technology originated from research led by Professor Greg Metha, professor of chemistry and acting director of the Centre for Energy Technology at the University of Adelaide.

Metha’s research group demonstrated hydrogen production using concentrated sunlight, water and a photocatalyst in 2021 and has subsequently developed photocatalytic reactor technology designed to operate under concentrated light.

SunHydrogen Chief Executive Tim Young said the testing provided external validation of the company’s technology and created a route towards pilot-scale demonstration.

“Seeing our modules tested above 10% solar-to-hydrogen efficiency, and produce more hydrogen as sunlight is concentrated, is exactly the kind of outside validation our shareholders want to see,” Young said.

Sparc Hydrogen Chief Executive Alana Barlow said the company had recorded solar-to-hydrogen efficiencies above 10% in laboratory testing and that the increase in hydrogen production under concentrated sunlight was an important result for its technology.

The next phase will focus on integrating SunHydrogen’s modules into Sparc Hydrogen’s reactor and testing their performance under progressively higher solar concentrations before moving to outdoor operation at the SHARP facility.

For SunHydrogen, the collaboration provides a pathway to test its technology in a concentrated solar environment while maintaining its focus on decentralised hydrogen production using sunlight and water. For Sparc Hydrogen, the programme offers an opportunity to assess whether the modules can contribute to lower-cost hydrogen production as its concentrated-sunlight technology moves towards pilot-scale development.