Magazine with Solar Cell Device Groups in Boats

The magazines are used in ConTEC for the feed and removal of samples from equipment during processing.

Concentrator Assemblies

R&D Services

Our R&D services comprise:

Integrating and connecting different cell concepts

Developing bespoke assembly designs

  • Planning and designing substrates (e.g. conductive path structure, substrate materials, active cooling)
  • Electrical contacting of components (bonding, welding and soldering processes)

Assembling small solar cell batches and developing production processes

Reliability and long-term stability testing

Concentrator photovoltaics employs cheap optics to focus light onto small solar cell surfaces, with different systems distinguished by their solar concentration factor. Our work primarily centers on low concentration (>1 - 50x) and high concentration (300 - 1000x) systems.

The solar cell assembly, comprising a substrate, solar cell and electrical contacts, is a key component in concentrator systems. Different system designs utilize different solar cell assembly structures, and we produce such assemblies with active and passive cooling systems in various sizes.

High concentration systems employ III-V multi-junction solar cells, and the development of such systems at Fraunhofer ISE is based at the Concentrator Technology and Evaluation Center (ConTEC).

Modified silicon or thin-film solar cells are used in low concentration modules. We develop these in our PV Module Technology Center (ModuleTEC) and at ConTEC, thus combining expertise in silicon flat-plate module technology and high concentration photovoltaics.

Research at ConTEC and the ModuleTEC primarily focuses on optimizing design, manufacturing processes and CPV module reliability. Our expertise in the field of thermal, optical and electrical simulation is shared with our clients, and we optimize and develop both manufacturing processes and innovative systems.

A variety of experimental methods are available for characterizing CPV components.

Selcted Research Projects


CPV-T System

CPV-T system combined with desalination systems




Highly efficient concentrator module with GaSb-based four-junction solar cell


Current publications - Concentrator Assemblies:

YearTitle/AuthorDocument Type
2017An end of service life assessment of PMMA lenses from veteran concentrator photovoltaic systems
Miller, D.C.; Khonkar, H.I.; Herrero, R.; Anton, I.; Johnson, D.K.; Hornung, T.; Schmid-Schirling, T.; Vinzant, T.B.; Deutch, S.; To, B.; Sala, G.; Kurtz, S.R.
Journal Article
2017The role of draft facets in temperature effects in silicone-on-glass Fresnel lens applications
Jakob, P.; Nitz, P.
Conference Paper
2016CPV-T Mirror Dish System Combined with Water Desalination Systems
Wiesenfarth, M.; Went, J.; Bösch, A.; Dilger, A.; Kec, T.; Kroll, A.; Koschikowsi, J.; Bett, A.W.
Conference Paper
2016High Efficiency GaInP/GaAs Tandem Wafer Bonded Solar Cell on Silicon: Presentation held at 3rd EU PV General Assembly 2016, University of Barcelona - Faculty of Physics Av. Diagonal, 647, Spain, 25.05.2016-26.05.2016
Cariou, R.; Benick, J.; Dimroth, F.
2016Improved in situ performance testing of line-concentrating solar collectors: Comprehensive uncertainty analysis for the selection of measurement instrumentation
Zirkel-Hofer, A.; Perry, S.; Fahr, S.; Kramer, K.; Heimsath, A.; Scholl, S.; Platzer, W.
Journal Article
2016Recent Development in Direct Generation of Hydrogen Using Multi-Junction Solar Cells
Ohlmann, J.; Sanchez, J.M.; Lackner, D.; Förster, P.; Steiner, M.; Fallisch, A.; Dimroth, F.
Conference Paper
2015CPV module with fresnel lens primary optics and homogenizing secondary optics
Wiesenfarth, M.; Dörsam, T.; Eltermann, F.; Hornung, T.; Siefer, G.; Steiner, M.; Riesen, S. van; Neubauer, M.; Boos, A.; Wanka, S.; Gombert, A.; Bett, A.W.
Conference Paper
2015NGCPV: A new generation of concentrator photovoltaic cells, modules and systems (a final review)
Datas, A.; Cristóbal, A.B.; Sala, G.; Anton Hernandez, I.; Minano, J.C.; Benítez, P.; Algora, C.; Bett, A.W.; Lackner, D.; Niemeyer, M.; Philipps, S.P.; Siefer, G.; Ekins-Daukes, N.J.; Roca, F.; Cancro, C.; Luque-Heredia, L.; Warmuth, W.; Baudrit, M.; Okada, Y.; Sugiyama, M.; Hishikawa, Y.; Takamoto, T.; Araki, K.; Fukuyama, A.; Nishioka, K.; Suzuki, H.; Kuze, N.; Moriyasu, Y.; Kita, T.; Kotagiri, A.; Kojima, N.; Martí Vega, A.; Yamaguchi, M.; Luque, A.
Conference Paper
2015Photoluminescence-based current-voltage characterisation of individual subcells in multi-junction devices
Alsonso-Álvarez, D.; Lackner, D.; Philipps, S.P.; Bett, A.W.; Ekins-Daukes, N.J.
Conference Paper
2015Solarenergie zur Stromerzeugung
Kiefer, K.
Book Article
2014High-Efficiency - A Key for CPV: Presentation held at CPV-10, 10th International Conference on Concentrator Photovoltaic Systems 2014, Albuquerque, USA, 08.04.2014
Bett, A.W.
2014III-V multi-junction solar cells
Philipps, S.P.; Bett, A.W.
Book Article
2014A Low Concentration Receiver Concept for Cost Effective Crystalline Back Contact Cells
Ebert, M.; Dörsam, T.; Fellmeth, T.; Hädrich, I.; Eitner, U.; Biro, D.; Wiesenfarth, M.; Noriega, P.; Caparros, S.; Castano, F.
Conference Paper
2014Modeling of concentrating photovoltaic and thermal systems
Helmers, H.; Bett, A.W.; Parisi, J.; Agert, C.
Journal Article
2014SOPHIA CPV module round robin: Power rating at CSOC
Steiner, M.; Siefer, G.; Baudrit, M.; Dominguez, C.; Anton, I.; Roca, F.; Fucci, R.; Pugliatti, P.M.; Stefano, A. di; Kenny, R.; Morabito, P.; Muller, M.
Conference Paper
2014SOPHIA CPV Module Round Robin: Power Rating at CSOC
Siefer, G.; Steiner, M.; Baudrit, M.; Dominguez, C.; Antón, , I.; Roca, F.; Fucci, F.; Pugliatti, P.; Stefano, A. di; Kenny, R.; Morabito, P.
Conference Paper
2014Strategic Vision on PV Research Infrastructure in Europe
Kroon, J.; Bruijne, M. de; Bennett, I.; Arrowsmith, G.; Malbranche, P.; Merten, J.; Assoa, Y.B.; Taylor, N.; Georgyvan, S.; Lauermann, I.; Hüpkes, J.; Siefer, G.; Köhl, M.; Warta, W.; Roca, F.; Theologitis, I.
Conference Paper
2013Advanced liquid cooling in HCPVT systems to achieve higher energy efficiencies
Zimmermann, S.; Helmers, H.; Tiwari, M.K.; Escher, W.; Paredes, S.; Neves, P.; Poulikakos, D.; Wiesenfarth, M.; Bett, A.W.; Michel, B.
Conference Paper
2013Analysis of high concentration passively cooled CPV module designs using mirror optics
Dreger, M.; Wiesenfarth, M.; Schmid, T.; Bett, A.W.
Conference Paper
2013Modeling the thermal runaway effect in CPV modules
Steiner, M.; Siefer, G.; Bett, A.W.
Conference Paper
2013Temperature dependent electroluminescence and voltages of multi-junction solar cells
Karcher, C.; Helmers, H.; Schachtner, M.; Dimroth, F.; Bett, A.W.
Conference Paper
This publication list has been generated from the publication database Fraunhofer-Publica.