Photo-electrochemical fuel generation: innovations in design, operation and application

Abstract: 

Solar fuel generation systems’ path towards commercialization rely on their competitiveness in terms of performance, longevity, cost and sustainability. First, I will discuss our research on modeling, characterizing and mitigating degradation in photoelectrochemical systems, where concentrated radiation can be used as one mean to accelerate degradation [1]. 

I will then transition towards more practical systems: thermally-integrated photo-electrochemical systems operating with concentrated light. I will discuss our journey from our laboratory scale demonstration (output power in the range of 10 W) under controlled irradiation conditions [2] to our demonstrator scale (output power in the range of 1 kW) under realistic solar irradiation conditions [3], and the planned industrial demonstrator (targeted output power in the range of 100 kW). 

I will provide data that shows and quantifies the operational stability of the system. I will discuss operational strategies that increase the competitiveness and capacity factor of the system, including strategies for 24h operation of the system or for constant hydrogen production rates. I will end with an outlook on how such systems can be further scaled to the MW scale, how they can be integrated in the current energy landscape, and how they can be extended to incorporate carbon-based inputs to contribute to the production of sustainable liquid fuels for application in aviation or long-haul transport of goods.

Biography: 

Sophia Haussener is an Associate Professor heading the Laboratory of Renewable Energy Science and Engineering at the Ecole Polytechnique Fédérale de Lausanne (EPFL). She received her MSc (2007) and PhD (2010) in Mechanical Engineering from ETH Zurich. Between 2011 and 2012, she was a postdoctoral researcher at the Joint Center of Artificial Photosynthesis (JCAP) and the Energy Environmental Technology Division of the Lawrence Berkeley National Laboratory (LBNL). She is a member of EPFL’s research award commission and of EPFL’s Academic Strategic Committee. She has published over 100 articles in peer-reviewed journals and conference proceedings, and 2 books. She has been awarded the ETH medal (2011), the Dimitris N. Chorafas Foundation award (2011), the ABB Forschungspreis (2012), a Starting Grant of the Swiss National Science Foundation (2014), the Prix Zonta (2015), the Global Change Award (2017), the Raymond Viskanta Award on Radiative Transfer (2019), the Yellott award (2024), and an ERC Consolidator Grant (2025). In 2024, she has been named one of Cell Press’ 50 Scientist that inspire. She is a co-founder of the startup SoHHytec aiming at commercializing photoelectrochemical hydrogen production. She is the former chair of the American Society of Mechanical Engineers’ (ASME) Solar Energy Division (2018), a former member of the Scientific Advisory Council of the Helmholtz Zentrum (2016-2022), a member of the scientific board of the Liquid Sunlight Alliance, and a member of the Ethics Board of Arete Ethik Invest.

Her current research is focused on providing design guidelines for thermal, thermochemical, and photoelectrochemical energy conversion reactors through multi-physics modeling and demonstrations. Her research interests include: thermal sciences and radiative transfer, fluid dynamics, charge transfer, and thermo/electro/photochemistry in complex multi-phase media on multiple scales.

EPFL - Sophia Haussener