Peter Tillmann

Peter Tillmann

Optimizing nanotextured solar cells for realistic weather conditions (2018 - 2023)

Currently, perovskite-silicon (pero-Si) tandem solar cells are the most investigated concept to overcome the theoretical limit for the power conversion efficiency of single-junction silicon solar cells, with is 29.4%. Optical simulations are extremely valuable to study the distribution of light within the solar cells, and allow to minimize losses from reflection and parasitic absorption. For monolithic perovskite-silicon solar cells, it is vital that the available light is equally distributed between the two subcells, which is known as current matching. Nanotextures have proven to strongly reduce reflective losses. In this project we investigate, how realistic weather conditions affect the performance of pero-Si modules. We study, how different light management approaches, such as pyramidal texturing or (sinusoidal) nanotexturing influence the sensitivity of the solar module to the illumination condition. In contrast to single-junction silicon solar cells, (two-terminal) tandem solar cells are more sensitive to the spectral distribution of the incident light.

Peer-reviewed Publications (journal or conference)

  1. P. Tillmann, K. Jäger, and C. Becker (2020). Minimising the levelised cost of electricity for bifacial solar panel arrays using Bayesian optimization. Sustainable Energy Fuels, 4, 254-264.
  2. K. Jäger, P. Tillmann, E.A. Katz, and C. Becker (2020). Perovskite/silicon tandem solar cells: Effect of luminescent coupling and bifaciality. Sol. RRL.
  3. K. Jäger, P. Tillmann, and C. Becker (2020). Detailed illumination model for bifacial solar cells.Opt. Express, 28, 4, 4751-4762.
  4. P. Tillmann, B. Bläsi, S. Burger, M. Hammerschmidt, O. Höhn, C. Becker, and K. Jäger (2021).  Optimizing metal grating back reflectors for III-V-on-silicon multijunction solar cells.Opt. Express, 29, 22517. doi: 10.1364/OE.426761
  5. P. Tillmann, K. Jäger, A. Karsenti, L. Kreinin, and C. Becker (2022). Model-Chain Validation for Estimating the Energy Yield of Bifacial Perovskite/Silicon Tandem Solar Cells.Sol. RRL, 202200079.


Other (presentations at conferences or preprints)

  1. P. Tillmann, C. Becker, and K. Jäger. Analysing the angular reflection losses of bifacial solar cells.  (Poster presentation), European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC), Online, 7-11 September 2020.
  2. P. Tillmann,  K. Jäger, E.A. Katz, and C. Becker. Relaxed current-matching constraints in perovskite/silicon tandem solar cell by bifacial operation and luminescent coupling. (Oral presentation), IEEE Photovoltaic Specialists Conference (PVSC), Online, 20-25 June 2021.
  3. P. Tillmann, K. Jäger, A. Karsenti, L. Kreinin, and C. Becker. Validation of Energy Yield Model for Bifacial Solar Cells and Prediction of Perovskite/silicon Tandem Solar Cell Performance. (Poster presentation), TandemPV, Freiburg, Germany, 30 May - 1 June 2022.