SmartCalc.CTM FAQ

1. What does SmartCalc.CTM do?

SmartCalc.CTM is a software tool to individually analyze the numerous effects contributing to the cell-to-module ratio of a PV module. By using elaborate scientific models SmartCalc.CTM is also capable of predicting the CTM of new module concepts, materials or module setups. In this way it is possible to identify critical factors impacting performance before building physical prototypes.

2. Is a registration required to use SmartCalc.CTM and what does a license cost?

The software is licensed by Fraunhofer ISE. A registration and a valid software license are necessary to run SmartCalc.CTM. Please contact us for available packages. A free demo version with a limited number of features and materials will be available soon.

3. Is data transferred to Fraunhofer ISE or third parties?

No transfer of data from or to Fraunhofer ISE or third parties and no access to cloud computing systems are necessary to perform calculations with SmartCalc.CTM. Neither Fraunhofer ISE nor any third party receives your module designs, material data, calculation results or any other data. No network access to a Fraunhofer ISE server is necessary. The software is “stand alone” and all data is stored locally.

4. Do the calculations require internet connection, high performance computers, access to cloud computing systems or other special equipment?

No internet connection is required to run SmartCalc.CTM.

No high performance computers are necessary to successfully run SmartCalc.CTM. Common desktop or laptop computers running Windows (64 bit) and the Matlab runtime (provided together with installation of SmartCalc.CTM) are sufficient.

5. Is it possible to enter own values and change module and material parameters?

Yes, most properties of materials and module setups can be edited within the graphical user interface and spectral data can be loaded from comma separated text files. There are only a few (technical) limitations regarding data input mostly to prevent errors.

6. Can we create or load material data files other than provided by Fraunhofer ISE?

Yes, you can load other materials, edit existing materials and save them as complete new material data files.

Please contact your supplier for material data files to import into SmartCalc.CTM.

If you are a material supplier or software developer you can contact us to learn about how to create a material data file for your customers or to create an interface to SmartCalc.CTM.

There are some technical limitations in editing selected material information but most material and module parameters can be changed within the GUI.

SmartCalc.CTM open data concept

7. Do I need Fraunhofer ISE to run calculations, create material data files or perform characterization measurements?

No. All calculations can be performed without input of Fraunhofer ISE. Module setups, material files or necessary characterization measurements can be performed without Fraunhofer ISE.

8. Does Fraunhofer ISE provide material files to import into SmartCalc.CTM?

Most commonly used materials in PV modules have already been characterized by Fraunhofer ISE. Due to legal reasons we are unable to provide this data without permission of the material supplier to the software user. Please contact your supplier for permission, material data files, data to create material files or samples of the material.

Material suppliers may contact us for a detailed guide to create material data files.

Material samples provided by a SmartCalc.CTM-user can be characterized at Fraunhofer ISE. Please ask for a service offer.

The software is shipped with a basic package of reference material data files. Other files can be easily integrated.

9. Are special measurements required to perform a CTM-analysis with SmartCalc.CTM and can the measurements be only performed at Fraunhofer ISE?

A complete and precise analysis requires data input for module materials and their interactions. This data can be obtained from the material supplier, literature or any other laboratory. The methodology and the single gain and loss factor calculations have been published by Fraunhofer ISE and measurements can be performed accordingly. If data is already available or previous experiences in CTM-analysis allow the estimation of input parameters no additional measurements are necessary. Depending on the availability of data from other sources and the desired degree of accuracy measurements may be advised to guaranty reliable results.

Fraunhofer ISE is not necessary to perform the CTM-analysis or the recommended measurements. Measurement results from other sources can be used.

10. Is documentation provided together with the software?

Yes, we provide a user manual and scientific publications explaining the methodology and single loss factors in detail.

11. What kind of materials can be used for calculation and what kind of modules can be calculated?

The flexibility of the scientific models behind SmartCalc.CTM allow the calculation of conventional glass-foil laminates, double-glass modules as well as new concepts such as shingled modules or TPedge (glass-air-glass).

Front cover: All kind of module front cover materials are possible, as the input data is the spectrally resolved transmission and reflection as well as the thickness. Especially glass (with and without anti-reflection coating), transparent foils or polymer sheets are possible.

Encapsulant: All kind of module encapsulants are possible, as the input data is the spectrally resolved transmission and reflection as well as the thickness. Especially polymer foils (EVA, PVB, TPO etc.), silicone or even air are possible.

Cell: All kinds of solar cells are possible, as the input data are selected electrical parameters, the spectral response, reflectance and geometrical information regarding contact terminals. Possible are (examples): solar cells with 5” or 6” wafer size (full square and pseudo square, full cells and half cells), busbars and contact pads, back-contact (MWT, IBC etc.) or front-back solar cells or cells for shingle interconnection.

Rear cover: All kind of module rear cover materials are possible, as the input data is the spectrally resolved transmission and reflection as well as the thickness. I.e. white, black or transparent backsheets or glass are possible.

Interconnection: Several interconnection technologies are possible. Input parameters include geometrical information of interconnectors and electrical terminals and material data allowing i.e. ribbon based interconnection with rectangular ribbons or round wires, light harvesting ribbons, soldering or electrical conductive adhesives as well as shingling or - depending on the complexity of the electrical design – electrical conductive backsheets.

12. Will the software be updated and will there be new features available?

Yes, we will continue developing new scientific models and are adding additional program features.

Even more module, cell and interconnector concepts will be possible in later versions. We aim to replace measurements with calculations or simulations. Also precision and usability will be continuously improved. Our goal is to achieve maximum flexibility for module concepts, data availability and desired level of details of the CTM-analysis.

Please check the news sections and publications for new features. Also check the license packages for future access to new features.

Reported bugs and errors will be fixed as soon as possible and will not need a new license.

13. How are the single gain and loss factors calculated?

The calculation is performed using published and validated scientific models. Please see the documentation of SmartCalc.CTM or the scientific publications.

While some models are simple and require only a few input variables other k-factors are calculated using highly complex algorithms. Additionally the flexibility of the models regarding different cell, module and interconnection concepts leads to increased complexity of some calculations. A detailed presentation of every calculation step for some k-factors can therefore not be provided.

14. How do I measure the single gain and loss factors?

The measurement of the CTM-ratio itself is a simple process: measure all the cells and compare the cell power/efficiency with the power/efficiency of the module. SmartCalc.CTM analyzes the single influence factors which is more complex.

While some factors are easy to measure or to calculate (i.e. inactive module margin area) other factors can only be measured together and are then attributed to single factors by the model. Please see the documentation for more details.