Select Page

Abstract: Solar radiation is the most abundant energy source available but it is distributed and intermittent, thereby necessitating its storage via conversion to a fuel (e.g. hydrogen or carbohydrates) for practical use. Solar thermo-chemical and photo-electro-chemical approaches (and combinations thereof) provide viable routes for the direct synthesis of solar fuels. The former make use of (concentrated) solar radiation as the energy source of process heat to drive endothermic chemical reactions, while the latter use photon energy for charge generation to drive electrochemical reactions. Both approaches involve complex interactions between multi-mode heat transfer, multiphase flow, charge transfer, and chemical reaction.

First, I focus on cost competitive photo-electrochemical (PEC) devices. The functionality of PEC devices relies on complicated and coupled multi-physics processes, occurring at multiple temporal and spatial scales. Device modelling can actively and efficiently support the choice of the most promising – in terms of efficiency, cost, robustness, scalability, and practicability – conceptual design pathways, material choices, and operating approaches1. I review the development of our PEC model framework2. I then show how we used this model to design and implement a PEC device with a solar-to-fuel efficiency of 17%. Finally, I discuss ongoing scaling approaches by our lab for the design, implementation, and testing of these devices, in order to bridge the gap between research and practical application.

Second, I discuss our work on high-temperature electrolysis for the production of fuels. I review the techno-economic modeling3, as well as receiver-reactor modeling followed by experimental demonstration of the approach and an outlook on a more integrated solar-driven thermo-electrochemical hydrogen generation.

I finish by comparing the various solar fuel generation pathways and compare the challenges and future pathways of the different, complementing processing routes.

References

  1. M. Dumortier, S. Tembhurne and S. Haussener, Energy Environ. Sci., 8:3614–3628, 2015.
  2. S. Y. Tembhurne and S. Haussener, Journal of The Electrochemical Society, 163:H1008-H1018, 2016.
  3. M. Lin and S. Haussener, Solar Energy, Solar Energy, 155:1389-1402, 2017.

Biosketch: Sophia Haussener is an Assistant Professor heading the Laboratory of Renewable Energy Science and Engineering at the Ecole Polytechnique Fédérale de Lausanne (EPFL). Her current research is focused on providing design guidelines for thermal, thermochemical, and photoelectrochemical energy conversion reactors through multi-physics modeling. Her research interests include: thermal sciences, fluid dynamics, charge transfer, electro-magnetism, and thermo/electro/photochemistry in complex multi-phase media on multiple scales. 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 has published over 60 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), the Prix Zonta (2015), and the Global Change Award (2017), and is a recipient of a Starting Grant of the Swiss National Science Foundation (2014). She is a deputy leader in the Swiss Competence Center for Energy Research (SCCER) on energy storage, serves as an Associate Editor for the Journal of Renewable and Sustainable Energy, and acts as a Member of the Scientific Advisory Council of the Helmholtz Zentrum.

Date/Time:
Date(s) - Feb 02, 2018
2:00 pm - 3:00 pm

Location:
38-138 Enginnering-IV
420 Westwood Plaza, Los Angeles CA 90095