The Software

SmartCalc.CTM cell-to-module losses software screen

Cell to Module Analysis by Fraunhofer ISE

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.

flexible virtual prototyping

free choice of module materials

front or back glasses of variable thickness and optical properties

encapsulation materials with different transmittance and UV-cut-offs

opaque or transparent backsheets with different reflectance

wide range of solar cell technologies

variable cell sizes and geometries in full or pseudo square format

front-back or back-contact (MWT, IBC)

variable geometry and position of busbars or pads

flexible module layout

cell and string spacing

adjustable module border width

number of cells and strings

several interconnection possibilities

rectangular ribbons or round wire interconnection

soldering or electrical conductive adhesives

interconnection with variable number of ribbons

IBC interconnection, conductive backsheets and shingled cells


Detailed cell-to-module analysis

SmartCalc.CTM waterfall-diagram cell-to-module-losses
SmartCalc.CTM waterfall-diagram cell-to-module-losses

Calculation of 15 loss and gain factors based on material properties and module setup

SmartCalc.CTM cell-to-module loss gain factors
SmartCalc.CTM cell-to-module loss gain factors
SmartCalc.CTM cell-to-module loss gain factors
SmartCalc.CTM cell-to-module loss gain factors
k Factor Description
k1 Module margin Inactive area at the module margin
k2 Cell spacing Inactive area between cells and strings
k3 Cover reflection Reflection of light at the front interface of the module
k4 Cover absorption Absorption of light in the front cover
k5 Cover/encapsulant reflection Reflection of light at the interface between front cover and encapsulation material
k6 Encapsulant absorption Absorption of light in the encapsulation material
k7 Interconnection shading Shading of the cell by interconnector ribbons
k8 Cell/encapsulant coupling Reduced reflection of the cell due to encapsulation (refractive index matching)
k9 Finger coupling Reflection of light from the cell metallization on the active cell area
k10 Interconnector coupling Reflection of light from the interconnector ribbons on the active cell area
k11 Cover coupling Internal reflection of light at the (rear) cover of the module in the cell spacing area
k12 Cell interconnection Electrical loss in cell interconnector ribbons
k13 String interconnection Electrical loss in cell string interconnectors
k14 Electrical mismatch Deviations in electrical cell parameters and from cell binning
k15 Junction box and cabling Electrical losses in cables and diodes of the junction box

Our open data concept

Enter and edit data

Users can enter and edit data directly in the SmartCalc.CTM user interface. Single parameters can be changed and spectral information loaded from comma separated text files.

Data generated by the user, data supplied by the material vendor as well as material characterization results from Fraunhofer ISE or the user itself can be used.
SmartCalc.CTM data input illustration

Create own data files

Editing and saving materials is easily possible. Fraunhofer ISE or additional licenses are not required to edit, save and load material data files.

Files containing material or module data can be loaded. Use previously saved material files as well as data files provided by your material supplier or Fraunhofer ISE.

Save and load data files

Data files can be created by saving from the SmartCalc.CTM user interface or by using a text-editor.

No proprietary program or licenses are necessary to create or edit the XML-data files.

Graphical User Interface

SmartCalc.CTM is equipped with a user-friendly interface to increase productivity. Data input, result presentation and detailed analysis are easy with SmartCalc.CTM.

SmartCalc.CTM cell-to-module screenshot layout setup

Configure your photovoltaic module via the user interface or load a predefined configurations or data files.

SmartCalc.CTM cell-to-module screenshot cell setup

Change cell specifications, encapsulation, backsheet or other materials easily and analyze the impact on module efficiency.

SmartCalc.CTM cell-to-module screenshot kfactors

Display results for individual factors in intuitive diagrams for quick analysis.

SmartCalc.CTM cell-to-module screenshot waterfall diagramm efficiency

Track your optimization and analyze existing modules or evaluate new concepts, materials or components.

Your Benefits

virtual prototyping

harvest performance potentials

increase module power

easier economic assessment

evaluate new concepts, materials and components

Licensing and services

Product licensing

We have different software packages, pricing plans and support options available. Please contact us to get an individual offer that fits your needs best.

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Free Trial

A demo version of SmartCalc.CTM is available for evaluation. Register below to receive your download link.

Get demo version

Service offers

You are developing new materials and would like to validate your specifications? Or you would like our support with customized interconnection concepts? We are here to help you! Contact us for a full list of our service offers or send us your inquiry.

Module Technology
at Fraunhofer ISE

New Features?

If your application requires a new feature or you would like to help us develop specific parts of the software, contact us about R&D projects.

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We perform electrical and optical and coupled measurements on materials and components.

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Get your demo version of SmartCalc.CTM

Demo Version Full Version
Module design
  • One junction box only
  • Free module dimensioning
  • Multiple junction boxes
Solar cells
  • Square H-pattern solar cells
  • No cell mismatch considered
  • Rectangular solar cells with free dimensioning
  • Several possible metallization patterns
  • IBC, MWT, H-pattern and shingle
  • Mismatch calculation possible
  • Rectangular ribbons
  • Serial string interconnection
  • Rectangular ribbons
  • Round wire interconnection
  • Shingled solar cells
  • Serial and parallel string interconnection
Data import
  • Choice of module layout, cells and interconnection
  • Encapsulant and backsheet data hard coded
  • All components can loaded from external data files
Result export
  • Limited export
  • Full export
Material database
  • Basic materials
  • Extended database
Third Party Use* Personal use only
no transfer of results to third parties
Use for third parties possible
Support* No support Personal support by Fraunhofer ISE
License time 3 Months 1 year



* Conditions apply

Frequently Asked Questions

Go to the FAQ page

If you have any further questions please don't hesitate to contact us.