Passivated emitter and rear cell (PERC) concept with an already developed roadmap for 24% efficiency will be leading the photovoltaics industry in the upcoming years. In a few industrial pilot lines, efficiencies above 22% have already been attained. Pilot lines have important roles in bridging lab scale proven concepts with the products which are ready for mass production. Therefore, GUNAM Photovoltaic Line which is specialized on PERC concepts has been established to overcome the barriers that hinder the performance of c-Si solar cells in PERC concepts in a relevant environment. The aim of this article is to show how a loss analysis can be employed in a practical way in an industrially relevant environment. The analysis depends on the first results of the studies from 6 months ramp up period of GPVL A batch of standard PERC type solar cells with p-type base and atomic layer deposited Al2O3 rear passivation have been fabricated during the ramp up of the line. A detailed gain-loss analysis was performed to address the optical, electrical and recombination losses in order to increase the cell efficiency. (C) 2019 Elsevier Ltd. All rights reserved.