Pyrolysis and PV (Professors Kray and Biollaz)
By mid of the century photovoltaics will be the most important energy source according to estimations of the International Energy Agency (IEA). The research group PnP, headed by Prof. Dr. Heide Biollaz and Prof. Dr. Daniel Kray, develops in particular pioneering production processes of solar cells and modules. The focus is set on strategic product development for medium-sized machine construction companies in the field of solar module manufacturing. Currently, a laboratory is under construction where new process technologies will be developed to the point where they can be transferred by companies into the prototype phase. The research activities are supported by comprehensive characterization systems, for example photo- and electroluminescence, REM/STEM and high-resolution confocal microscopy.
Furthermore, the so-called negative emission technologies (NET) are being researched. The focus is on PyCCS (pyrogenic carbon capture and storage), which produces vegetable carbon from biological residues in addition to pyrolysis oils and gases. This can be used in a variety of applications to permanently store carbon from the CO2 in the air and thus actively cool the earth. Of particular interest is the cascade use in agriculture (animal feed, manure treatment, fertiliser additive, soil improvement), which is investigated in the project "FYI: Agriculture 5.0": fyi-landwirtschaft5.org.
Publikationen Forschungsgruppe PnP
(1) Reviewed Journals
- Jannis Grafmüller, Hans-Peter Schmidt, Daniel Kray, Thomas D. Bucheli, Haike Mäurer, Jens Möllmer, Heiko Peisert, Nikolas Hagemann, "Biochar acidification increased sorption and reduced leaching of nitrate", Journal of Environmental Management, Volume 393, 2025, 127224, ISSN 0301-4797, https://doi.org/10.1016/j.jenvman.2025.127224. (https://www.sciencedirect.com/science/article/pii/S0301479725032001)
- M. Domènech Monfort, A. Sandhaas, E. Zozmann, C. Pönisch, D. Kray, N. Hartmann, "Energy system transformations toward zero emissions: A focus on pyrolysis", Energy Conversion and Management: X, Volume 26, 2025, 101052, ISSN 2590-1745, https://doi.org/10.1016/j.ecmx.2025.101052. (https://www.sciencedirect.com/science/article/pii/S2590174525001849)
- Grafmüller, J., Möllmer, J., Muehe, E.M. et al. "Granulation compared to co-application of biochar plus mineral fertilizer and its impacts on crop growth and nutrient leaching". Sci Rep 14, 16555 (2024). https://doi.org/10.1038/s41598-024-66992-0
- Domènech Monfort, Meritxell and Sandhaas, Anna and Zozmann, Elmar and Pönisch, Christoph and Kray, Daniel and Hartmann, Niklas, The Role of Pyrolysis as a Negative Emission Technology in Future Energy Systems. Available at SSRN: https://ssrn.com/abstract=4606539 or http://dx.doi.org/10.2139/ssrn.4606539
- Grafmüller, J.; Schmidt, H.-P.; Kray, D.; Hagemann, N. "Root-Zone Amendments of Biochar-Based Fertilizers: Yield Increases of White Cabbage in Temperate Climate". Horticulturae 2022, 8, 307. https://doi.org/10.3390/horticulturae8040307
- D. Kray et al., "N.I.C.E.-Wire: Next Generation Robust Eco-Friendly Bifacial PV Modules With High Efficiency," in IEEE Journal of Photovoltaics, vol. 12, no. 1, pp. 38-44, Jan. 2022, doi: 10.1109/JPHOTOV.2021.3124168.
(2) Konferenzbeiträge
- P. Leibiger, C. Pönisch, T. Seifert, D. Kray, "Paving the Way for Low Breakage Rates in Industrial Production of N.I.C.E.-Wire Modules", World Conference on Photovoltaic Energy Conversion (8. : 26-30 September 2022 : Milan, Italy), https://doi.org/10.4229/WCPEC-82022-3DV.1.7
- D. Reinwand, P. Wiechers, D. Kray, "NEW DEVICE FOR ACCURATE Measurement of busbarless Bifacial Solar Cells by Using N.I.C.E.™ Technology“, 37th EU-PVSEC 2020, online.
- Dirk Reinwand, Benedikt King, Joerg Schube, Frédéric Madon, Roland Einhaus, Daniel Kray, "Lab-scale Manufacturing of Medium-sized N.I.C.E.TM Modules with High-efficiency Bifacial Silicon Heterojunction Solar Cells", AIP Conference Proceedings 2156, 020009 (2019); https://doi.org/10.1063/1.5125874
- D. Reinwand, D. Pysch, N. Bay, J. Burschik, H.H. Kuehnlein, F. Madon, R. Einhaus, A. Brand, V. Arya, B. Smith, D. Richter, D. Kray, "All Copper NICE Modules", 7th World Conference on Photovoltaic Energy Conversion, June 10-15, 2018, Waikoloa, Hawaii, USA
(3) Sonstige Veröffentlichungen
- D. Kray, N. Hagemann, C. Pönisch, Strategien für pflanzenkohlebasierte Düngung -Klassifizierung der Produkte Landwirtschaftliche Dekarbonisierung mit Pflanzenkohle, November 2023, DOI: 10.13140/RG.2.2.14907.39201, Conference: German Biochar Forum 2023, Berlin, Germany
- Harald Bier, Helmut Gerber, Marcel Huber, Hannes Junginger, Daniel Kray, Jörg Lange, Hansjörg Lerchenmüller, Pål Jahre Nilsen, "EBI Whitepaper - Mit Pflanzenkohle basierten Kohlenstoffsenken dem Klimawandel entgegenwirken", www.biochar-industry.com/why
Team PnP
- 0781 205-4906
- jannis.grafmueller@hs-offenburg.de
- Room: 1.01
- Badstraße 24, 77652 Offenburg
- 0781 205-4881
- christoph.poenisch@hs-offenburg.de
- Room: 1.01
- Badstraße 24 Offenburg
- 0781 205-4915
- vishal.satheesh@hs-offenburg.de
- Room: 2.06
- Badstraße 24, 77652 Offenburg