Development of hybrid concentrator/flat-plate photovoltaic technology to reach the highest energy yield

Abstract: In this cumulative thesis, a novel hybrid photovoltaic module combining the concentrator and flat plate approach (CPV/PV), named EyeCon, is developed and characterized. Conventional concentrator photovoltaic (CPV) modules use highest efficiency III-V multi-junction solar cells and convert up to 38.9% of the direct sunlight. Nevertheless, the use of concentrating optics prevents them from absorbing the diffuse part of the solar spectrum. On the other hand, flat plate silicon (Si) photovoltaic (PV) modules convert light from all angles of incidence with efficiencies around 20%. This work focuses on the enhancement of a multi-junction CPV module by the integration of bifacial Si PV cells to obtain the highest power output per unit area through the conversion of direct, diffuse and rear side irradiance.

The development and manufacturing of the EyeCon module consisted of the design of the 4-terminal circuit of the CPV and flat plate PV cells, the optimization of the metallization grid of the bifacial Si PV cells under partial illumination, the thermal validation of using the Si PV cells as heat spreaders for the CPV cells and the development of a seamless process that integrates the flat plate PV cells into a CPV module with minimum additional steps and materials.

The main optical, thermal and electrical characterizations include the quantification of the effective amount of irradiance absorbed by the Si PV cells under the concentrating optics, the effect of tracker misalignment on power output when the focal spot moves from the CPV receivers onto the flat plate PV cells, the definition of hybrid reference standard conditions and filtering criteria and the development of a power rating procedure for hybrid CPV/PV bifacial modules.

The analysis of the EyeCon module performance under different meteorological and spectral conditions comprises the power output under a hypothetical voltage-matched interconnection between the CPV and the bifacial PV cells, the extensive worldwide energy yield modeling and the techno-economic comparison with CPV and single-junction flat plate PV modules.

Under the scope of this research, a world record efficiency of 34.2% and a bifacial power output beyond 350 W/m2 at standard test conditions were reached using III-V four-junction CPV and flat plate bifacial Si PV cells. Furthermore, hybrid CPV/PV technology is expected to generate up to 1150 kWh/m2 in subtropical arid regions, whereas in places like Europe, China, central Africa and Latin America a 25 - 35% higher yield than its closest contender is expected. Thus, hybridization is a promising path towards increasing the competitiveness of conventional CPV technology

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Universität Freiburg, Dissertation, 2021

Classification and Topics

• Classification: Elektrotechnik, Elektronik
• Keyword: Power resources ; Technology ; Energy harvesting ; Konzentrator ; Bifacial-Solarzelle ; Energy Harvesting

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2022
• Creator: Martinez Sanchez, Juan Francisco
• Contributor: Glunz, Stefan ; Fraunhofer-Institut für Solare Energiesysteme ; Albert-Ludwigs-Universität Freiburg. Institut für Nachhaltige Technische Systeme ; Albert-Ludwigs-Universität Freiburg. Fakultät für Angewandte Wissenschaften

Further information

• DOI: 10.6094/UNIFR/226417
• URN: urn:nbn:de:bsz:25-freidok-2264177
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 25.03.2025, 1:55 PM CET