Daily generation profile Irregularities

[JamesLenton]

Hello, 

Please can you help explain why irregularities like the one shown in the image attached occur in PVsyst? In this instance power drops from 15 MW to 0 MW in 30 minutes, mid-day in the summer.

To me this seems impossible, even with partial cloud cover. Could be a result of poor weather data, however I experience similar things with Meteonorm and PVGIS.

[Linda Thoren]

Hello,

To better understand the results, you can consider adding additional parameters—such as irradiance—to assess whether a drop in production is due to variations in weather data or other factors.

 

In the Advanced Simulations, you also have the option to export hourly data as a .csv file, allowing for deeper analysis of any relevant simulation parameters.

[JamesLenton]

Hello,

The cause of the drop appears to be the irradiation. Do you know why this could occur, it seems unrealistic.

[Linda Thoren]

Indeed it seems a bit surprising that the global irradiance would be 0 for a few hours in the middle of the day, but indeed possible. Using another weather data provider, do you see similar drops in irradiance?

If you import a weather file with missing data, these hours will be considered as 0 in PVsyst.