Accuracy of historical solar radiation data



I’m using Solcast 5 minutes historical solar radiation data for my research at UNSW. As we may know that BOM and many literature have flagged about the overestimation of satellite data during cloudy/wet conditions and the underestimation during clear sky/dry conditions. I have a couple of questions regarding the accuracy:

  1. Have the historical solar radiation data provided by Solcast been corrected?
  2. Does Solcast have documentation about accuracy of data and data correction procedure?



Hi Kanyawee

Thanks for using our data, and sorry for this delayed reply. We are stoked that students and researchers are getting use out of Solcast data.

Regarding Question 1 “corrected” - in short yes, BUT - another round of such corrections is being performed currently; this data will be updated in ~ mid August.

Regarding Question 2 documentation and accuracy, some independent validation papers are currently in draft, these should be available in the next month or two as well. BoM pyranometer sites have been flagged as having possible QC issues in data >2016, which is a potential complicating factor.

Your comment about clear VS cloudy: Problem is that satellite cloud detention has a sensitivity lower bound - even good satellite methods like our Solcast proprietary method tend to sometimes miss thin clouds, and for zero overall bias this means that clouds become slightly thicker to compensate.

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