Abstract:
Photovoltaic power is a crucial renewable energy source that has the potential to enhance
a city’s sustainability. However, in order to identify the various issues that may occur during the
lifespan of a photovoltaic module, solar module inspection techniques are crucial. One valuable
technique that is commonly used is luminescence, which captures silicon emissions. This article
focuses on a specific luminescence technique called partial photoluminescence. This technique
involves illuminating a specific portion of the solar cell surface and recording the luminescence
emission generated in the remaining area. This method has been trialed in a laboratory environment,
utilizing infrared LEDs as the excitation source. An analysis of the main parameters that affect
the technique is provided, where pictures have been taken under varying exposure times ranging
from 50 ms to 400 ms, irradiance levels ranging from 200 W/m2 to 1000 W/m2, and a percentage
of illuminated cells ranging from 10% to 40%. Furthermore, the experimental device has been
modified to generate images utilizing sunlight as the excitation source. Several pictures of damaged
cells were taken under an irradiance range of 340 W/m2 to 470 W/m2. The quality of the partial
photoluminescence images is comparable to conventional electroluminescence images, but longer
exposure times are required.
