Optimization of the output power by effect of backsheet reflectance and spacing between cell strings

In the cell to complete module process, the cell to module (CTM) loss is inevitable. In typical process, the CTM power loss is larger than 3%. In this letter, we tried to reduce the CTM loss by studying the backsheet reflectance and the string inter space effect. The conclusion was carried out basing on the both simulation and experiment results. It shows if the reflectance of backsheet is from 70% to 90%, the power gain will be improved ~0.3%. We also show the CTM loss decreases with the increasing string inter space. Around 0.3% less CTM loss can be achieved by changing the string inter space. In the end, we conclude that the CTM loss can be reduced from 3% to 2.28% by combining these two beneficial effects.