Glass evaluation

The glass of a module and especially its resistivity is crucial for the PID susceptibility of a module. Hence the glass needs to be investigated separately from the influence of the solar cell and the EVA.

Glass evaluation

Table 1: Ion analysis of the investigated glass types by ICP
Fig. 1: PIDcon measurement with the same type of solar cell and EVA foil and different glass types
Fig. 2: dependency of the decrease in parallel resistance on the glas type [1]
 

Since the PV community became aware of the PID problem, a lot of investigations have been made and it became clear that not only the solar cell itself and its SiNx layer, but also the encapsulation material has a huge influence on the PID susceptibility of the module. Besides the polymer foil the glass has to be investigated.

The PIDcon enables the investigation of the influence of the glass on the PID susceptibility. In the PIDcon a sample stack is used, which simulates a module. The user simply has to put in a solar cell, the EVA foil and on top of that the glass that should be investigated. Of course solar cells from the same batch as well as the same EVA foil have to be used for comparison. In table 1 the ion analysis of the different investigated glass types by ICP is displayed.

For more information please read:
[1] V. Naumann, Ursachenanalyse und physikalische Modellbildung für potenzial-induzierte Degradation von Silizium-Solarzellen, Dissertation, Martin-Luther-Universität Halle-Wittenberg (2014)