High-Concentration Systems (HCPV)

R&D Services

Our R&D services comprise designing, producing and characterizing concentrator modules and components, as well as analyzing complete systems:

Concentrator Modules

Production Processes

Modeling, Design and Simulation

Reliability and Long-Term Durability Testing

Characterizing CPV System Components

We develop high concentration photovoltaic systems that allow III-V multi-junction solar cells to be used for terrestrial applications. To do so, we analyze and assess optical components that concentrate sunlight by a factor of 300-1000 before it is converted into electrical energy using III-V multi-junction solar cells. Within the field of concentrator systems, we work to develop and refine the entire technology chain from solar cells, concentrator optics and module production through dedicated electronics to complete systems and monitoring. One key integral part in this technology is the development of concentrator modules, which is coordinated at Fraunhofer ISE in the Concentrator Technology Evaluation Center (Con-TEC). Research at Con-TEC primarily focusses on optimizing design, manufacturing processes and CPV module reliability. Our expertise in the field of thermal, optical and electrical simulation is offered to our clients, and we optimize and develop processes and innovative systems.

For more than two decades, we have been developing our lens based FLATCON® technology devised at Fraunhofer ISE. The module uses Frensel lenses produces with the silicone-on-glass (SoG) technology to concentrate the solar radiation. On this technology, our novel hybrid module EyeCon is based. It converts direct, diffuse and - with bi-facial PV cells - even the rear irradiance into electricity to increase the power output further. For cost reduction, we investigate micro-CPV modules.
Beside of modules with lenses as primary optics, we develop module concepts using mirror optics as concentrators to reach high geometrical concentrations. On system level, we are researching the co-generation of heat and electricity in concentrating systems with the goal of reaching system efficiencies of over 70%.

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

Within the field of high concentration PV systems, we develop concentrator modules and systems. We follow an holistic approach that includes optical, thermal, mechanical and electrical aspects and offer:

  • Integration and testing of innovative new cells in concentrator modules
  • Modules with solar cells from few hundred micrometres to few square centimetres
  • Experimental investigation of new concepts and components (e.g. integration of secondary optics) for CPV
  • Design optimization and analysis using finite element methods (FEM) and computational fluid dynamics (CFD)
  • Pilot and small production batches using automated manufacturing technologies (e.g. pick & place; bonded, adhesive and soldered joints, electrical interconnection)
  • Reliability and long-term stability testing
  • Lab and field measurements including power rating

Selected Research Projects



Development of a low-cost and high efficient solar module using a solar cell with 5-pn junctions



Development of a Highly Concentrating CPV Module Based on Modern Micro-Production Technology



Research cooperation on innovative climate technology



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



Solar Hydrogen Generation using a HyCon System


Current publications - High-Concentration Systems (HCPV):

YearTitle/AuthorDocument Type
2021Technical Boundaries of Micro-CPV Module Components: How Small is Enough: Presentation held at 17th International Conference on Concentrating Photovoltaic Systems (CPV), Online Conference, Germany, 12.-14. April 2021
Wiesenfarth, M.; Martínez, J.F.; Steiner, M.; Iankov, D.; Nitz, P.; Dimroth, F.; Helmers, H.
2021Technical Boundaries of Micro-CPV Module Components: How Small is Enough?: Paper presented at 17th International Conference on Concentrating Photovoltaic Systems, CPV 2021, Online, Germany, 12.-14.04.2021
Wiesenfarth, M.; Iankov, D.; Martínez, J.F.; Nitz, P.; Steiner, M.; Dimroth, F.; Helmers, H.
2020Development and Outdoor Characterization of a Hybrid Bifacial HCPV Module
Martinez, J.; Steiner, M.; Wiesenfarth, M.; Fellmeth, T.; Dörsam, T.; Wiese, M.; Glunz, S.W.; Dimroth, F.
Journal Article
2019CPVIndia - Energy Yield Forecasting with PVsyst
Steiner, M.; Wekkeli, A.; Ojha, S.; Sardar, S.; Singh, V.; Singh Sawhney, H.; Singh Chandok, J.; Siefer, G.
Conference Paper
2019FLATCON® CPV Module Technology: A New Design based on the Evaluation of 10 Years of Outdoor Measurement Data
Wiesenfarth, M.; Steiner, M.; Dörsam, T.; Siefer, G.; Dimroth, F.; Nitz, P.; Bett, A.W.
Conference Paper
2019Outdoor Experimental Characterization of Novel High-Efficiency High-Concentrator Photovoltaic (HCPV) modules Using Achromatic Doublet on Glass (ADG) Fresnel Lenses as Primary Optics
Vallerotto, G.; Wiesenfarth, M.; Victoria, M.; Steiner, M.; Anton, I.; Jost, N.; Askins, S.; Sala, G.
Conference Paper
2019Pushing Energy Yield with Concentrating Photovoltaics
Steiner, Marc; Wiesenfarth, Maike; Martínez Sánchez, Juan Francisco; Siefer, Gerald; Dimroth, Frank
Conference Paper
2019Validierung von Methoden für den Zuverlässigkeitsnachweis von Konzentratorsolarzellen
Eltermann, Fabian; Wilde, Jürgen (Referent); Glunz, Stefan W.; Bett, Andreas W. (Betreuer)
20184-terminal CPV module capable of converting global normal irradiance into electricity
Martínez, Juan F.; Steiner, Marc; Wiesenfarth, Maike; Dimroth, Frank
Conference Paper
2018Analysis of the performance of an on-axis mirror module design compared to a FLATCON module
Wiesenfarth, Maike; Gamisch, Sebastian; Jakob, Peter; Steiner, Marc; Bett, Andreas
Conference Paper
2018Challenges in the Design of Concentrator Photovoltaic (CPV) Modules to Achieve Highest Efficiencies
Wiesenfarth, M.; Anton, I.; Bett, A.W.
Journal Article
2018Component cell-based restriction of spectral conditions and the impact on CPV module power rating
Steiner, Marc; Muller, Matt; Siefer, Gerald; Bett, Andreas W.
Journal Article
2018Evaluation of 53 kW CPV system in India: Presentation held at 14th International Conference on Concentrator Photovoltaic Systems 2018, Puertollano, Spain, 16.04.2018-18.04.2018
Steiner, M.; Bösch, A.; Wekkeli, A.; Ojha, S.; Sardar, S.; Singh, J.; Singh, V.; Singh Chandok, J.; Siefer, G.
2018Operation & maintenance - the key for reliable performance in a CPV power plant
Wüllner, Johannes; Steiner, Marc; Wiesenfarth, Maike; Bett, Andreas
Conference Paper
2018Systematic design evaluation on the example of a concentrator photovoltaic module with mirror optics and passive heat dissipation
Wiesenfarth, Maike; Gamisch, Sebastian; Jakob, Peter; Steiner, Marc; Bett, Andreas
Journal Article
2018Trends in Solar Electricity: Presentation held at EuroSun, 12th International Conference on Solar Energy for Buildings and Industry 2018, Rapperswil, Switzerland, September 11th, 2018
Bett, A.W.
2017Concentrating photovoltaic systems
Steiner, M.; Gerstmaier, T.; Bett, A.W.
Book Article
2017Uncertainty estimation of spectral matching ratio based power rating of CPV modules
Steiner, M.; Siefer, G.; Bett, A.W.
Conference Paper
201643 % direct sunlight conversion efficiency using 4J cell with achromatic full glass lens
Steiner, M.; Siefer, G.; Schmidt, T.; Wiesenfarth, M.; Dimroth, F.; Bett, A.W.
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
2016Rating of CPV modules: Results of module round robins
Steiner, Marc; Siefer, Gerald; Baudrit, Mathieu; Askins, Stephen; Domínguez, César; Antón, Ignacio; Roca, Francesco; Fucci, Raffaele; Cancro, Carmine; Romano, Antonio; Graditi, Giorgio; Pugliatti, Paola Maria; Stefano, Agnese di; Kenny, Robert; Norton, Matthew; Minuto, Alessandro; Morabito, Paolo; Muller, Matthew; Riley, Daniel; Pratt, Larry
Conference Paper
2016Recent Development in Direct Generation of Hydrogen Using Multi-Junction Solar Cells
Ohlmann, J.; Martínez, Juan F.; Lackner, D.; Förster, P.; Steiner, M.; Fallisch, A.; Dimroth, F.
Conference Paper
2015Analysis of the output of two isotype cell sets compared to a precicion spectroradiometer
Norton, M.; Galleano, R.; Siefer, G.; Steiner, M.; Kenny, R.; Zaaiman, W.
Conference Paper
2015Challenges and perspectives of CPV technology: Presentation held at 42nd IEEE Photovoltaic Specialists Conference 2015, New Orleans, USA, 14.06.2015-19.06.2015
Bett, A.W.
2015CPV module design optimization for advanced multi-junction solar cell concepts
Steiner, M.; Kiefel, P.; Siefer, G.; Wiesenfarth, M.; Dimroth, F.; Krause, R.; Gombert, A.; Bett, A.W.
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
2015A high-efficiency hybrid high-concentration photovoltaic system
Zimmermann, S.; Helmers, H.; Tiwari, M.K.; Paredes, S.; Michel, B.; Wiesenfarth, M.; Bett, A.W.; Poulikakos, D.
Journal Article
2015Quantum efficiency measurement of concentrator photovoltaic modules
Mundus, M.; Rapp, C.; Missbach, T.; Siefer, G.; Hohl-Ebinger, J.; Bett, A.W.; Warta, W.
Conference Paper
2015Technical analysis and optimization of a high concentrating photovoltaic power tower
Ordóñez Moreno, K.; Heimsath, A.; Wiesenfarth, M.; Schöttl, P.; Nitz, P.
Conference Paper
2015YieldOpt, a model to predict the power output and energy yield for concentrating photovoltaic modules
Steiner, M.; Siefer, G.; Hornung, T.; Peharz, G.; Bett, A.W.
Journal Article
2014Challenges for Thermal Management and Production Technologies in Conchotovoltaic (CPV) Modules
Wiesenfarth, M.; Gamisch, S.; Dörsam, T.; Bett, A.W.
Conference Paper
2014Development and Investigation of a CPV Module with Cassegrain Mirror Optics
Dreger, M.; Wiesenfarth, M.; Kisser, A.; Schmid, T.; Bett, A.W.
Conference Paper
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.
2014Highly Efficient Multi-junction Solar Cells
Bett, A.
2014III-V multi-junction solar cells and concentrating photovoltaic (CPV) systems
Philipps, S.P.; Bett, A.W.
Journal Article
2014Investigation of Different Fresnel Lens Designs and Methods to Determine the Optical Efficiency
Wiesenfarth, M.; Steiner, M.; Wolf, J.; Schmidt, T.; Bett, A.W.
Conference Paper
2014Similarities and Differences between Terrestrial CPV and Space Multi-Junction Solar Cells: Presentation held at 10th European Space Power Conference 2014, Noordwijkerhout, Netherlands, 13.04.2014-17.04.2014
Bett, A.W.
2014SPICE network simulation to calculate thermal runaway in III-V solar cells in CPV modules
Steiner, Marc; Siefer, Gerald; Bett, Andreas W.
Journal Article
2013Analysis of high concentration passively cooled CPV module designs using mirror optics
Dreger, M.; Wiesenfarth, M.; Schmid, T.; Bett, A.W.
Conference Paper
2013Conceptual product development with integrated concentrating PV systems - CPV in the built environment from a designer's perspective
Reinders, A.; Wiesenfarth, M.; King, R.R.
Conference Paper
2013Design criteria for robust and secure next generation CPV control systems
Benoit, P.; Fey, S.; Rohbogner, G.; Kohrs, R.; Wittwer, C.; Georg, D.; Wüllner, J.; Gombert, A.
Conference Paper
2013Efficiency of dense-array CPVT module with front-side interconnected cells
Polonsky, G.; Shelef, G.; Flitsanov, Y.; Wiesenfarth, M.; Steiner, M.; Helmers, H.; Bett, A.W.; Kribus, A.
Conference Paper
2013Investigations on 3-dimensional temperature distribution in a FLATCON-type CPV module
Wiesenfarth, M.; Gamisch, S.; Kraus, H.; Bett, A.W.
Conference Paper
2013Ko-Generation von Elektrizität und Wärme aus konzentriertem Sonnenlicht: Überblick über Technologie und Anwendungen
Helmers, H.
Book Article
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.