Long Term Testing over 6 Years on Crystalline Silicon Solar Modules with Snail Trails

In this paper, the influence of the snail trails on the performance and long-term reliability of solar modules were investigated in detail by six years of tracking test of 4 solar modules with snail trails. The results show that the snail trails have no obvious expansion over the six years. And the average power degradation of the snail trails was 0.6% per year, which is in the normal range. These results indicated that the snail trail is only an appearance defect, which has no obvious negative effect on the electrical performance of solar modules.