21 October, 2022 Due to the observed increase of n-type panel C&I installations, the research on the performance of P-PERC and N-TOPCon modules in real world became an important topic from the practical point of view. This comparison was carried out by a third party institute CAS （Chinese Academy of Science） at a solar commercial rooftop system located in Ningbo, intending to help C&I system planners to choose photovoltaic modules taking into account the actual operating conditions.