How to calculate "Estimated Power"

Does anyone knows how the “Estimated Power” is calculated (formular) ?
I would like to write a script, that compares the “Estimated Power” with the “Generated Power” to count the hours of sunshine. Thanks for any hint

I use the efficiency figure on pvoutput which is calculated by Generation/system size, as to the hours of sunshine solar panels receive.
https://pvoutput.org/list.jsp?userid=545

Hi, You might also like to look at< Live view page > then go to < Analyse > 5 over from live on the same line Jim

Thanks for the answers. Maybe may question is not clear. I want to know, how the “Estimated Power” is calculated. So far, I’ve found a nice Python project “pysolor” that makes it easy to calculate the insolation, altitude, and azimut of the sun. Maybe this will help do calculate the estimated power on a sunny day.
If my generating power is in the range of the expected --> sun is shining
If my generating power is far below of expected --> no sun.
I guess this will work good during the day, but on dawn and dusk ???

ok it worked out from what you put in settings for your system and the temperature at your location.

and i am think by estimated power you mean the isolation ???

Click “Your Outputs”–>live–>Insolation
move your mouse over the blue curve. Here it says “Estimated Power”.
I just want to know, how this value is calculated. I know there are using the possition of the sun, array tilt, system size, and facing of the panel. I just want to know the formula (mathematical) for my own calculation

sorry unable to tell you that as i don’t know how its done

OK, anyway, thanks for your help and have a nice weedend