Hi, thanks for the details.
Yes, the effect on Solar plant depend on the altitude. The plant is located at almos 1800 msnm. (High).
I have been looking at the different clouds reports but they dont show a forecast (right?). So, I have been checking the satellite to see where the clouds are heading. For example, yesterday the forecast of GFS and ECMWF forecastes sunny (no clouds) and MeteoBlue forecastes some clouds during the morning, at the same time the satellite shows no clouds heading to Copiapó. But today we had more clouds than what we were expecting. You can check it searching for Copiapó. Out of the blue, a few small group of clouds comming from the ocean created a bunch of heavy clouds around Copiapó impacting my forecast. I dont know how forecast the clouds with more accuracy. If you have any idea please let me know.
The sun position can help me too. I will check the pulging.