Photocatalytic water splitting prototype a success

Sparc Technologies has announced to the ASX that Sparc Hydrogen has successfully tested its second-generation prototype photocatalytic water splitting (PWS) reactor at the CSIRO Energy Centre in Newcastle, New South Wales. The completion of the second round of prototype testing was delivered on time and on budget by the Sparc Hydrogen team.

Sparc Hydrogen is a joint venture between the University of Adelaide, Fortescue and Sparc Technologies.

The design of the second-generation prototype has built on learnings from the first round of testing completed in Q4 2023. Performance of the reactor over numerous trial runs and a range of concentrated solar and thermal operating conditions is significantly improved compared to the first-generation prototype, with better temperature and pressure control, gas production and measurement, according to the announcement. Hydrogen gas production was close to that which was estimated based on laboratory results using the same photocatalyst material, providing validation for laboratory testing under concentrated solar simulation going forward.

The second-generation prototype has been designed to be easily scalable in order to slot into a linear Fresnel concentrated solar field for pilot scale testing, which is subject to Sparc Hydrogen board approval of Stage 2 of the joint venture.

"Sparc is very pleased with the progress in reactor design made over a short period of time by the hard-working Sparc Hydrogen team,” said Sparc Technologies Managing Director Nick O’Loughlin. “The performance and design improvements that have been demonstrated through the second-generation reactor validate the ongoing laboratory work along with the approach that Sparc Hydrogen has taken to on-sun scale-up as we head towards a pilot plant investment decision.

“This prototype testing has persuasively demonstrated concentrated photocatalytic water splitting (PWS) in real-world conditions, which in turn reinforces the significant potential of PWS as an alternative to electrolysis for the production of low-cost green hydrogen.”

Sparc believes that the success of this round of prototyping — which has been supported through funding from Australia’s Economic Accelerator (AEA) grant program and the CSIRO Kick-Start Program — has fully satisfied the objectives set out at the beginning of the prototype testing.

In parallel with the recent on-sun prototype testing, Sparc Hydrogen has continued to progress development workstreams for the pilot plant ahead of a decision to move to Stage 2 of the joint venture. A pre-FEED study completed by an external consultant during Q4 2023 demonstrated the ability for Sparc Hydrogen to build and fund a pilot plant incorporating modular, scalable linear Fresnel concentrated solar mirrors. If built, this would be a first-of-its-kind facility demonstrating the combination of photocatalytic water splitting with concentrated solar in an end-to-end green hydrogen production system.

Image credit: CSIRO.