Auriane Canesse

Dear Chen, Thank you for forwarding this article, it is an interesting study. However, most of the conclusion is misleading: PVsyst doesn't use the Module temperature in the simulation but rather the cell temperature. The cell temperature is not measured directly in this study (it would require placing temperature sensor inside a module during fabrication). The difference between module temperature and cell temperature is corrected for in section 3.4 and the coefficients Uc and Uv are recomputed there. These values (table 6) correspond physically to what should be used in PVsyst. The range found is ~[29-32] which is reasonably close to our default recommendation. Note that the authors also mention that the model used to compute cell temperature has not been validated for their specific technology, so the results should be taken with a grain of salt.

Hello Chen, We did not carry out dedicated studies on how array pitch affects the heat dissipation. However, the thermal losses are indeed influenced by the PV module support structure and it affects the convective cooling on the back plane. The advised U coefficients corresponding to each structure type are described here: https://www.pvsyst.com/help/project-design/array-and-system-losses/array-thermal-losses/index.html#u-value-determination It is also possible to measure the U coefficient values for your installation as explained here: https://www.pvsyst.com/help/project-design/array-and-system-losses/array-thermal-losses/u-value-measurement.html

Hello James, If the dip in irradiance is not due to missing data, I would need your files to look into this issue in more detail. Could you send your project at support@pvsyst.com ? Auriane