ReRa Solutions and Solliance present a new analysis system for solar cells and modules

Solar cell and module analysis

Solar cells and modules are often characterized by ‘current voltage’ measurements, which are currently executed with multifunctional analysis equipment. These tools can place voltages on samples, for short, but also for longer periods, and analyze the output current. However, the existing tools (“Keithley Source-meters”) are relatively expensive and only allow the use for one solar cell or module at the time.

Within the TKI iDEEGO project TRUST, ReRa Solutions has developed and built a new type of electrical load, which allows both long and short term exposure to external voltages. The capabilities of this load have been studied and presented by Solliance in Eindhoven.

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Integration into degradation setup

Mirjam Theelen, researcher at Solliance commented: ‘We have developed and built two hybrid degradation setups ( in partnership with Eternal Sun and Hielkema Testequipment. These setups allow the exposure of solar cells and mini-modules to humidity, elevated temperatures and illumination. However, for better simulation of the field behavior of such samples, we needed to continuously place them under bias voltages. This for example allows exposure to ‘maximum power point’ conditions, which is a standard field condition, or to ‘reverse bias’, which occurs when modules are partially shadowed.’

ReRa Solutions has built and installed multiple electronics loads  that allow these voltage biases in these hybrid degradation setups. During the project, these loads were optimized and used to test CIGS solar cells made at the Solliance facilities. An outcome of this project showed rapid degradation of cells under very high or very low biases, which therefore should not be used. Moreover, it was also demonstrated that cell performance can change when the electrical bias is varied. This is important information for large scale implementation of CIGS modules and has been presented at various scientific conferences in the spring of this year.

Example of electrical load

Example of electrical load

Further commercialization

Erik Haverkamp, director of ReRa Solutions commented:

‘Within the TKI project, we were able to develop a new electronic load system. This new modular product is a small and cost-effective solution for both cell and module analysis. With this tool, ReRa has extended its product range and is able to enter new markets. The great demand for these products already resulted in a few actual sales and numerous quotations worldwide.’


Solliance is the alliance of TNO, ECN, imec and Forschungszentrum Jülich, TU/e, Delft University, Hasselt University and Holst Centre for research and development in the field of thin film photovoltaic solar energy (PV) in the ELAT-region (Eindhoven-Leuven-Aachen triangle). Solliance’s ambition is to strengthen the position of the region as a world player in thin film PV.

ReRa Solutions (a Radboud University Nijmegen spin-off) is an expert in the field of solar cell measurement. ReRa has developed several dedicated instruments, reference solar cells and software for the measurement and calibration of different types of solar devices. Besides product development, ReRa offers consultancy and measurement equipment design for solar cell laboratories. The products of ReRa are used all over the world by most of the leading technology centers.