Solar module for building integration

The concept of the mosaic module allows an aesthetic and individual design of photovoltaic building façades.

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The Module Technology Center provides industrial equipment for module prototyping and analytic platforms for device characterization.

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Industrial Module Manufacturing

The IR-stringer allows high-throughput interconnection of 3, 4 and 5 busbar solar cells in half- and full-size formats.

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Colored Modules for Building Integration

The special layer set-up provides a very high color saturation and a very good angular color stability. Compared to an uncoated cover glass, the loss of generated solar power is only 7%.

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Shingle Cells

Shingle interconnection of solar cells with ECA on structured slimline EVA.

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Module Technology

R&D Services

Cell Interconnection

The interconnection of solar cells causes ohmic and optical losses in a module. We use various soldering technologies and industrial stringing equipment for measuring and optimizing the quality of the joints.


With advanced characterization methods we are able to analyse all aspects of laminate properties. We focus on fast and accurate methods to accelerate product and process development cycles.

Integrated Modules

We develop integrated module designs to meet specific requirements and create tailored product solutions.

Module Efficiency

Solar cells usually suffer from losses when integrated into a module. We analyze the effects down to the material level and assess the potential for optimization.

Fraunhofer ISE offers a comprehensive range of services for module product development and materials testing. We provide support for turning innovative ideas into reliable, efficient and competitive products, as well as for improving quality and efficiency in existing module and interconnection concepts.

Our research covers the integration of high-efficiency solar cells, reliable soldering processes, conductive adhesive technology, laminate-free edge-sealed solar modules and the cell-to-module (CTM) power and efficiency optimization.

We are able to develop, improve and test your products to meet industrial demands. Our excellently equipped Fraunhofer ISE Module Technology Center (Module-TEC) supports development from first ideas to module pilot manufacturing.

© Fraunhofer ISE
With SmartCalc.CTM, Fraunhofer ISE has developed a software that helps reduce the cell-to-module power losses in PV module manufacturing.

SmartCalc.CTM is a tool for the fast and precise calculation of cell-to-module losses and gains for solar modules.

The combination of sophisticated scientific models and measured data provide the basis for CTM loss analysis of a wide range of module concepts and materials. An intuitive graphical user interface allows for quick and easy virtual protoytyping.


© Fraunhofer ISE
Industrial stringer for the interconnection of solar cells at Module-TEC

Module-TEC offers extensive facilities to develop module technology. It fills the gap between laboratory development and industrial production technology by allowing relevant charge numbers and formats to be processed. In addition to production and processing technology, numerous analytical facilities are available for quality control. Our research is concentrating on connection technology for crystalline solar cells, integration of high-efficiency cells into modules and the analysis and optimization of module efficiency. In parallel, we are developing application-specific customized modules for building integration (BIPV) and integration into vehicles.

Selected Research Projects



High-Throughput Production System and Process Technology for Crystalline Silicon Solar Modules



Development of Vehicle-Integrated Photovoltaics for On-Board Charging of Electric Utility Vehicles


CTM 100+

Improving Module Performance by Analysis of Cell-to-Module Losses with SmartCalc.CTM

Latest Press Releases


Press Release - September 9, 2019

Fraunhofer ISE Presents Colored Solar Car Roof

The demand for electric vehicles is increasing worldwide. To extend the driving range, the Fraunhofer Institute for Solar Energy Systems ISE has developed a solar car roof with highly efficient solar cells. 


Press Release - January 9, 2019

Adhesive Process Developed for Shingle Cell Technology

The Fraunhofer Institute for Solar Energy Systems ISE in Freiburg has developed a special adhesive process to interconnect silicon solar cells for the industrial production of shingle modules. The market demand for shingle modules is rising rapidly due to their high efficiency and pleasing aesthetics. The cell stringer at Fraunhofer ISE is unique in Germany. It offers a wide range of possibilities for the prototype production of this highly efficient module.


Press Release - October 24, 2018

Joint Research by Fraunhofer ISE and Heraeus for High-performance Solar Modules

The Fraunhofer ISE and Heraeus are researching and optimizing novel, selectively coated cell connectors in a joint research project. The Selectively Coated Ribbon (SCRTM) cell connector achieves an average gain of 1.9 W in conventional 60-cell solar modules.

Downloads: Flyer of Module Technology

Brochure: Photovoltaic Module Technology

Flyer: SmartCalc.CTM: Precise Cell-to-Module Analysis

Flyer: Colored PV Modules for Building Integration

Flyer: Electrically Conducive Adhesives in PV Modules

Flyer: Increased Efficiency with Bifacial Shingle Modules

Flyer: Device-Integrated Photovoltaics

Flyer: Individual Designs for BIPV Modules

Current publications - Module Technology


YearTitle/AuthorDocument Type
2020Cell-To-Module (CTM) Analysis for Photovoltaic Modules with Cell Overlap: Paper presented at the 30th International Photovolatic Science and Engineering Conference (PVSEC) & Global Photovoltaic Conference (GPVC) 2020, Jeju, Republic of Korea, November 8 - 13, 2020
Shahid, J.; Karabacak, A.Ö.; Mittag, M.
Conference Paper
2020A Comparison of Different Solar Cell Technologies for Integrated Photovoltaics
Heinrich, M.; Kuhn, T.E.; Dimroth, F.; Würfel, U.; Goldschmidt, J.C.; Powalla, M.; Glunz, S.W.; Neuhaus, D.H.
Conference Paper
2020The Effect of Cell and Module Dimensions on Thermomechanical Stress in PV Modules
Beinert, A.; Romer, P.; Heinrich, M.; Mittag, M.; Aktaa, J.; Neuhaus, D.H.
Journal Article
2020Enabling the In-Situ Stress and Temperature Measurement by Silicon Solar Cell Integrated Stress and Temperature Sensors for Photovoltaic Modules
Beinert, A.J.; Imm, M.; Benick, J.; Becker, F.; Seitz, S.; Heinrich, M.; Paul, O.; Glunz, S.W.; Aktaa, J.; Eitner, U.; Neuhaus, H.
Conference Paper
2020Energy Yield Modelling of 2D and 3D Curved Photovoltaic Modules
Neven-du Mont, S.; Heinrich, M.; Pfreundt, A.; Kutter, C.; Tummalieh, A.; Neuhaus, D.-H.
Conference Paper
2020Enhancing PV Module Thermomechanical Performance and Reliability by an Innovative Mounting Solution
Beinert, A.; Masolin, A.
Conference Paper
2020Integrated Lightweight, Glass-Free PV Module Technology for Box Bodies of Commercial Trucks
Kutter, C.; Basler, F.; Alanis, L.E.; Markert, J.; Heinrich, M.; Neuhaus, D.H.
Conference Paper
2020Integrierte Photovoltaik - Aktive Flächen für die Energiewende
Wirth, H.; Vehse, M.; Rau, B.; Peibst, R.; Colsmann, A.; Stephan, A.; Lechner, P.
Conference Paper
2020More Realistic Consideration of Backsheets Coefficient of Thermal Expansion on Thermomechanics of PV Modules
Romer, P.; Oreski, G.; Beinert, A.J.; Neuhaus, H.; Mittag, M.
Conference Paper
2020Potential and Challenges of Vehicle Integrated Photovoltaics for Passenger Cars
Heinrich, M.; Kutter, C.; Basler, F.; Mittag, M.; Alanis, L.E.; Eberlein, D.; Schmid, A.; Reise, C.; Kroyer, T.; Neuhaus, D.H.; Wirth, H.
Conference Paper
2020Reduction of ECA Amount for the Ribbon Interconnection of Heterojunction Solar Cells
Kaiser, C.; Nikitina, V.; Geipel, T.; Kraft, A.
Conference Paper
2020Silicon Solar Cell-Integrated Stress and Temperature Sensors for Photovoltaic Modules
Beinert, A.J.; Imm, M.; Benick, J.; Becker, F.; Seitz, S.; Heinrich, M.; Paul, O.; Glunz, S.W.; Aktaa, J.; Eitner, U.; Neuhaus, H.
Journal Article
2020Spray Pyrolysis - a Versatile Technique for Thin Film Deposition in PV
Bartsch, J.; Heitmann, U.; Jakob, L.; Mahmoud Algazzar, R.; Tutsch, L.; Hermann, R.; Kluska, S.; Bivour, M.; Bläsi, B.; Hauser, H.; Janz, S.; Glatthaar, M.
Conference Paper
2020Trend Tracking of Efficiency and CTM Ratio of PV Modules
Tummalieh, A.; Pfreundt, A.; Mittag, M.
Conference Paper
2019Accelerated TC Test in Comparison with Standard TC Test for PV Modules with Ribbon, Wire and Shingle Interconnection
Schiller, C.; Rendler, L.C.; Eberlein, D.; Mülhöfer, G.; Kraft, A.; Neuhaus, D.-H.
Conference Paper
2019Adhesion Improvement for Solder Interconnection of Wet Chemically Coated Aluminum Surfaces
Rose, Angela de; Kamp, M.; Mikolasch, G.; Kraft, A.; Nowottnick, M.
Conference Paper
2019Differential Scanning Calorimetry for Simulation and Optimization of the Lamination Process
Herzog, C.; Müller, T.; Heinrich, M.; Neuhaus, D.-H.
Conference Paper
2019Enabling the Measurement of Thermomechanical Stress in Solar Cells and PV Modules by Confocal Micro-Raman Spectroscopy
Beinert, A.; Büchler, A.; Romer, P.; Haueisen, V.; Rendler, L.C.; Schubert, M.C.; Heinrich, M.; Aktaa, J.; Eitner, U.
Journal Article
2019FEM Simulation of Deformations in Strings of Shingled Solar Cells Subjected to Mechanical Reliability Testing
Klasen, N.; Romer, P.; Beinert, A.; Kraft, A.
Conference Paper
2019FEM Simulation of Thermomechanical Stress in PV Modules: Presentation held at 14. SiliconFOREST 2019, Falkau, Germany, 24.02.2019-27.02.2019
Beinert, A.
2019Industrialization of Ribbon Interconnection for Silicon Heterojunction Solar Cells with Electrically Conductive Adhesives
Geipel, T.; Nikitina, V.; Bauermann, L.P.; Fokuhl, E.; Schnabel, E.; Erath, D.; Krieg, A.; Kraft, A.; Fischer, T.; Lorenz, R.; Breitenbücher, D.
Conference Paper
2019Interconnection of Silicon Heterojunction Solar Cells by Infrared Soldering - Solder Joint Analysis and Temperature Study
Rose, Angela de; Geipel, T.; Eberlein, D.; Kraft, A.; Nowottnick, M.
Conference Paper
2019Lead-free Solders for Ribbon Interconnection of Crystalline Silicon PERC Solar Cells with Infrared Soldering
Geipel, Torsten; Eberlein, Dirk; Kraft, Achim
Conference Paper
2019Lead-free Solders for Ribbon Interconnection of Crystalline Silicon PERC Solar Cells with Infrared Soldering
Geipel, T.; Eberlein, D.; Kraft, A.
Conference Paper
2019Post-Processing Thickness Variation of PV Module Materials and its Impact on Temperature, Mechanical Stress and Power
Pfreundt, A.; Yucebas, D.; Beinert, A.J.; Verissimo Mesquita, L.; Pitta Bauermann, L.; Romer, P.; Mittag, M.
Conference Paper
2019Techno-Economic Analysis of Half-Cell Modules - the Impact of Half-Cells on Module Power and Costs
Mittag, M.; Pfreundt, A.; Shahid, J.; Wöhrle, N.; Neuhaus, D.H.
Conference Paper
2019Thermal Modelling of Photovoltaic Modules in Operation and Production
Mittag, M.; Vogt, L.; Herzog, C.; Pfreundt, A.; Shahid, J.; Neuhaus, D.H.; Wirth, H.
Conference Paper
2019Thermochemical Stress in Solar Cells: Contact Pad Modeling and Reliability Analysis
Rendler, L.; Romer, P.; Beinert, A.; Stecklum, S.; Kraft, A.; Eitner, U.; Wiese, S.
Journal Article
2019Thermomechanical Evaluation of New PV Module Designs by FEM Simulations
Beinert, A.; Romer, P.; Heinrich, M.; Mittag, M.; Aktaa, J.; Neuhaus, D.H.
Conference Paper
2018Analysis of Grain-Size Distribution and Yield Strength of Interconnector Ribbons and Wires at Different Streching Conditions Using Color Etching
Walter, J.; Stegmaier, J.; Kraft, A.; Eitner, U.
Conference Paper
2018Approach for a Holistic Optimization from Wafer to PV System
Mittag, M.; Reise, C.; Wöhrle, N.; Eberle, R.; Schubert, M.; Heinrich, M.
Conference Paper
2018Comparison of Layouts for Shingled Bifacial PV Modules in Terms of Power Output, Cell-to-Module Ratio and Bifaciality
Mondon, A.; Klasen, N.; Fokuhl, E.; Mittag, M.; Heinrich, M.; Wirth, H.
Conference Paper
2018Decorated Building-Integrated Photovoltaic Modules: Power Loss, Color Appearance and Cost Analysis
Kutter, C.; Bläsi, B.; Wilson, H.R.; Kroyer, T.; Mittag, M.; Höhn, O.; Heinrich, M.
Conference Paper
2018Electrically conductive adhesives for photovoltaic modules
Geipel, Torsten; Rissing, Lutz (Referent); Maier, Hans Jürgen (Referent)
2018Light Attenuation Model to Predict Nominal Power of Modules with Light-Scattering Ceramic Printed Front Glasses
Kutter, C.; Wilson, H.R.; Pfreundt, A.; Heinrich, M.; Wirth, H.
Conference Paper
2018Mechanical and electrical properties of wave-shaped wires for low-stress interconnection of solar cells
Rendler, L.; Walter, J.; Goldenberg, S.; Beinert, A.J.; Wiese, S.; Eitner, U.
Journal Article
2018Mosaic Module Concept for Cost-Efficient and Aesthetic BIPV Modules
Mittag, M.; Ebert, M.; Wilson, H.R.; Fellmeth, T.
Conference Paper
2018A Multidimensional Optimization Approach to Improve Module Efficiency, Power and Costs
Shahid, J.; Mittag, M.; Heinrich, M.
Conference Paper
2018Optimization of electrically conductive adhesive bonds in photovoltaic modules
Geipel, T.; Meinert, M.; Kraft, A.; Eitner, U.
Journal Article
2018Rapid Calculation of the Backsheet Coupling Gain Using Ray Groups
Pfreundt, A.; Mittag, M.; Heinrich, M.; Eitner, U.
Conference Paper
2018Solder joint analysis on coated aluminum for silicon solar cell interconnection
Rose, Angela de; Kraft, A.; Eitner, U.; Nowottnick, M.
Conference Paper
2017Abgedeckter PVT-Kollektor mit Low-e-Beschichtung und Belüftung als Überhitzungsschutz
Lämmle, M.; Panzer, C.; Hermann, M.
Conference Paper
2017Analysis of backsheet and rear cover reflection gains for bifacial solar cells
Mittag, M.; Grünzweig, A.; Wiese, M.; Mahmoud, N.; Schmid, A.; Heinrich, M.
Conference Paper
2017Analysis of peel and shear forces after temperature cycle tests for electrical conductive adhesives
Hoffmann, S.; Geipel, T.; Meinert, M.; Kraft, A.
Conference Paper
2017Cell-to-Module (CTM) analysis for photovoltaic modules with shingled solar cells: Paper presented at 44th IEEE Photovoltaic Specialists Conference 2017, Washington, DC, USA, 25.06.2017-30.06.2017
Mittag, M.; Zech, T.; Wiese, M.; Bläsi, D.; Ebert, M.; Wirth, H.
Conference Paper
2017Electrical and thermal modeling of junction boxes
Mittag, M.; Kutter, C.; Hoffmann, S.; Romer, P.; Beinert, A.J.; Zech, T.
Conference Paper
2017FEM-based development of novel back-contact PV modules with ultra-thin solar cells
Beinert, Andreas; Leidl, Roman; Sommeling, Paul; Eitner, Ulrich; Aktaa, Jarir
Conference Paper
2017Intermetallic compounds in solar cell interconnections: Microstructure and growth kinetics
Geipel, T.; Moeller, M.; Walter, J.; Kraft, A.; Eitner, U.
Journal Article
2017Low-temperature soldering for the interconnection of silicon heterojunction solar cells
Rose, Angela de; Erath, D.; Geipel, T.; Kraft, A.; Eitner, U.
Conference Paper
2017Power loss through decorative elements in the front glazing of BIPV modules
Mittag, M.; Kutter, C.; Ebert, M.; Wilson, H.R.; Eitner, U.
Conference Paper
2017Ribbon interconnection of 6" BC-BJ Solar Cells
Walter, Johann; Rendler, Li Carlos; Halm, Andreas; Mihailetchi, Valentin; Kraft, Achim; Eitner, Ulrich
Journal Article
2017Shingled cell interconnection: A new generation of bifacial PV-modules
Klasen, N.; Mondon, A.; Kraft, A.; Eitner, U.
Conference Paper
2017Solar potential on commercial trucks: Results of an irradiance measurement campaign on 6 trucks in Europe and USA
Eitner, U.; Ebert, M.; Zech, T.; Schmid, C.; Watts, A.; Heinrich, M.
Conference Paper
2017Solder interconnection of aluminum foil rear side metallization for passivated emitter and rear solar cells
Rose, Angela de; Kraft, A.; Gledhill, S.; Ali, M.T.; Kroyer, T.; Pscherer, C.; Graf, M.; Nekarda, J.; Eitner, U.
Conference Paper
2017Solder joint stability study of wire-based interconnection compared to ribbon interconnection
Walter, J.; Rendler, L.C.; Ebert, C.; Kraft, A.; Eitner, U.
Journal Article
2017Systematic PV-module optimization with the cell-to-module (CTM) analysis software "SmartCalc.CTM"
Mittag, M.; Ebert, M.
Journal Article
2017Thermomechanical stress analysis of PV module production processes by Raman spectroscopy and FEM simulation
Beinert, A.J.; Romer, P.; Büchler, A.; Haueisen, V.; Aktaa, J.; Eitner, U.
Journal Article
2017TPedge: Progress on cost-efficient and durable edge-sealed PV modules
Mittag, M.; Eitner, U.; Neff, T.
Conference Paper
2017Ultra-soft wires for direct soldering on finger grids of solar cells
Rendler, L.C.; Walter, J.; Kraft, A.; Ebert, C.; Wiese, S.; Eitner, U.
Journal Article
2016A comprehensive study of intermetallic compounds in solar cell interconnections and their growth kinetics
Geipel, T.; Moeller, M.; Kraft, A.; Eitner, U.
Journal Article
2016Comprehensive Study of Intermetallic Compounds in Solar Cell Interconnections Including Lead-Free, Low Melting Point Solders
Geipel, T.; Möller, M.; Kraft, A.; Eitner, U.
Conference Paper
2016The impact of ribbon properties on measured peel forces
Eitner, U.; Rendler, L.C.
Journal Article
2016Influence of Photovoltaic Module Mounting Systems on the Thermo-Mechanical Stresses in Solar Cells by FEM Modelling
Beinert, A.J.; Ebert, M.; Eitner, U.; Aktaa, J.
Conference Paper
2016Investigation of Thermomechanical Stress in Solar Cells with Multi Busbar Interconnection by Finite Element Modeling
Rendler, L.C.; Kraft, A.; Ebert, C.; Wiese, S.; Eitner, U.
Conference Paper
2016Low-temperature interconnection of PVD-aluminium metallization
Geipel, T.; Kumm, J.; Moeller, M.; Kroely, L.; Kraft, A.; Eitner, U.; Wolf, A.; Zhang, Z.; Wolfahrt, P.
Journal Article
2016Mechanical stress in solar cells with multi busbar interconnection - parameter study by FEM simulation
Rendler, L.C.; Kraft, A.; Ebert, C.; Eitner, U.; Wiese, S.
Conference Paper
2016Mosaic modules for improved design options in building integrated photovoltaic modules
Ebert, M.; Mittag, M.; Fellmeth, T.; Spribille, A.; Mindehoud, T.; Gijzen, G.; Fath, K.; Hecker, R.; Eitner, U.
Conference Paper
2016Die parasitäre Kapazität eines PV-Moduls als Ursache für einen erhöhten Ableitstrom und Indikator für den Feuchteeintrag im Verkapselungsmaterial
Berg, H.; Hsian Saw, M.; Philipp, D.
Conference Paper
2016Photovoltaic Modules: Technology and Reliability
Wirth, H.; Weiß, K.-A.; Wiesmeier, C.
2016A PVT collector concept with variable film insulation and low-emissivity coating
Lämmle, M.; Thoma, C.; Hermann, M.
Journal Article
2016TPEDGE: Glass-glass photovoltaic module for BIPV-applications
Mittag, M.; Neff, T.; Hoffmann, S.; Ebert, M.; Eitner, U.; Wirth, H.
Conference Paper
This publication list has been generated from the publication database Fraunhofer-Publica.