Highly efficient and low cost photovoltaic-electrolysis (PVE) system to generate hydrogen by harvesting the full spectrum of sunlight

Photovoltaic electrolysis (PVE) is a promising approach to produce renewable hydrogen (H2) for export from sunlight and water. The main obstacle to utilising photovoltaic electrolysis to produce H2 is the high cost and modest efficiency. The project aims to lower the cost of renewable hydrogen produced via PVE by improving the energy efficiency of transition metal-based alkaline water electrolysers and the overall solar to hydrogen (STH) conversion efficiency of PVE systems. This approach is anticipated to lead to the development of an integrated PVE system demonstrating an overall solar-to hydrogen conversion efficiency >30%.

How the project works
This hydrogen generation project uses innovative approach to develop a low-cost, highly efficient, integrated PVE system to harvest the whole spectrum of sunlight as the sole source of electricity, heat and light, which in turn powers an alkaline water electrolyser to convert renewable primary energy (solar) to hydrogen. To achieve this outcome, UNSW will be using world’s highest efficiency Concentrator Photo Voltaic (CPV) receivers from Raygen and novel electrocatalyst composites already developed at UNSW.

Together by both increasing the performance efficiency and lowering hydrogen production cost from electrolysis, thereby to achieving or surpassing the predicted hydrogen cost from PVE system (reported by CSIRO for 2030), this technology will help position Australia as a competitive and leading country for generating and exporting renewable hydrogen in emerging future hydrogen economy.

Area of innovation
Hydrogen as energy carrier poses several apparent advantages including readily attainable storage and transportation, clean and high energy density. The current technology used to produce over 90% of hydrogen stock is by steam reforming of methane. This project will use an integrated Photo-Voltaic Electrolysis (PVE) heat exchange technology and active and cost-effective catalyst materials to convert sunlight to hydrogen. The successful deployment of the PVE system will enable the production of H2 via a clean sustainable pathway and confirm Australia as a leader in renewable energy research and technology.

Schematic of PVE system

Funder: ARENA (2018 - 2022)

List of investigators: Scientia Prof Rose Amal, Dr Xunyu Lu, Dr Mark Keevers, Prof Chuan Zhao, A/Prof Yansong Shen, Prof Martin Green, Prof Liming Dai, Dr John Lasich (Raygen)