Humidity characterization and control in planar micro-tracking CPV modules

. To better understand the process of condensation formation in CPV modules, an experimental setup containing two Insolight mockup modules has been prepared to firstly, monitor the relevant variables involved in the internal dew point, namely the internal relative humidity and air temperature, the differential atmospheric pressure between the module and the environment and the temperatures of the front and rear parts of the modules, and secondly, to be able to modify the exchange conditions with the environment. After spending the wet season in Madrid (four months during the winter), the formation of condensation has been correlated with the monitored dew point and most of the time it disappears after a few hours. Considering that sealing the module would increase the internal pressure to the point of failure due to thermal expansion, the modules are always equalized through a breather. Hence, some preliminary mitigating actions have been studied such as the addition of desiccant and different venting configurations that seek to reduce the amount of humidity content and therefore help prevent the formation of the dew point.