Is the production slightly higher when arranged following the slope compared to the normal arrangement?

The author received a consultation: for a project in Guangxi, the yield (referring to the yield per kilowatt, the same below) of electricity generated by following the slope is surprisingly slightly higher than that when arranged directly facing south. After conducting Production calculations for two layout plans using Candela3D and PVsyst software, the Simulate results have verified the correctness of the conclusions. What exactly is the reason for that? The author has conducted an analysis on the actual terrain layout of the project, and the results are as follows: In the table above, the four normals highlighted in red account for nearly 70% of the total. Next, we will calculate the actual tilt and azimuth angles of the array for these four normals, using both due south and downslope arrangements, and employ PVsyst to compute the annual total radiation. It can be observed that for the aforementioned four orientations, when…