Solar tower power plants use thousands of heliostats and a fast and precise characterization of their optical defects constitutes an important technological obstacle. The objective of the thesis is to increase the capacities of an innovative method of characterization of the optical defects of heliostats. This patented backward-gazing method is developed at PROMES for two years. The thesis will consist in using a fluxmetry method on a white target, constituting the current state of the art, for the calibration of heliostats by combining it to the backward-gazing method with four cameras. The main operational parameters of the methods will be studied, discussed and optimized thanks to numerical simulation studies. The experimental backward-gazing and fluxmetry methods will be implemented at the solar tower facility THEMIS in Targassonne. The new optical hybrid method will be applied to some heliostats and validated by the check of the correction brought to the heliostat structure.
Title: Manufacturing of multijunction solar cells for HCPV
The Labex Solstice (French laboratory of excellence) offers a 1 year post-doc position at IES (Institut d’Electronique et des Systèmes, Montpellier, France - Group M@CSEE - Dr. Y. CUMINAL). The topic concerns the manufacturing of multijunction solar cells for HCPV. The fellow will work on projects aimed at exploring an innovative ways to fabricate multijunction solar cells using antimonide-based compounds (lattice matched to GaSb). In fact, these materials offer a wide range of bandgaps of interest between 0.726 and 1.64 eV.
This field is currently a hot topic due to:
- unoptimized state-of-the art solar cells for HCPV
- rare industrial development in this field
- unexplored potential of antimonide-based compounds
All fabrication steps take place in the IES, starting with the MBE growth followed by the technological steps.
The candidate will be involved in the technological fabrication steps in clean room following the epitaxial growth and the related characterizations.