ZHAW validates yield calculations for alpine solar systems
Researchers at ZHAW have tested the accuracy of the PVSyst software for estimating the yield of alpine solar installations. The results show that the yields are generally underestimated.
Researchers at the ZHAW have verified the accuracy of the PVSyst software’s calculations on the yield of alpine solar plants. The Swiss Federal Office of Energy recommends this software as part of the expansion of alpine solar plants, the ZHAW explains in a press release. The results of the research showed “that the approach proposed by the federal government makes sense and that the yields tend to be underestimated”, the press release explains.
For the validation, the ZHAW researchers carried out a large number of measurements on the Totalp in Davos GR in the winter months of 2023/24 using a flexible, multi-row miniature system. The measurement data largely matched the data collected at the same time from the existing test facility at the same location. In contrast, the yields calculated using the PVSyst simulation tended to be lower across the board.
The researchers attribute this to the albedo values from Meteonorm used by the software. Albedo is a value for the proportion of sunlight reflected from the ground. At the same time, the research was able to show that backside irradiation on a bifacial solar panel increases the yield by around 25 to 35 per cent.