F
FB.
I decided to look in more detail at my PV system's generation stats. It has only been operational for a few months, so hasn't seen a full year.
60% of days are below target for that day.
40% of days are above target for that day.
The system total generation is comfortably outperforming SAP.
But those days which are above target (when the sun shines), tend to be spectacularly above target and appear to be pulling up the averages; just as one millionnaire in a workplace would pull up the average wealth of the group; yet most would not be "average".
My data suggest that the data used for SAP calculations, when divided into daily stats (and adjusted for day length and sun position, so that, for example, the end of February should generate more than the beginning) probably quite closely estimate the median generation, but not the mean generation, which is pulled dramatically higher by a few really sunny days.
Does anyone else's data confirm this?
Any thoughts?
60% of days are below target for that day.
40% of days are above target for that day.
The system total generation is comfortably outperforming SAP.
But those days which are above target (when the sun shines), tend to be spectacularly above target and appear to be pulling up the averages; just as one millionnaire in a workplace would pull up the average wealth of the group; yet most would not be "average".
My data suggest that the data used for SAP calculations, when divided into daily stats (and adjusted for day length and sun position, so that, for example, the end of February should generate more than the beginning) probably quite closely estimate the median generation, but not the mean generation, which is pulled dramatically higher by a few really sunny days.
Does anyone else's data confirm this?
Any thoughts?