Python Script for SolCast Rooftop Accounts


I’ve made available a Python script on Github which

  • downloads and stores SolCast forecasts for Rooftop accounts (incl. the newly allowed split array configurations) in SQLite and/or Influx
  • using pvlib, it can do the same with OpenWeatherMap cloud data (and German centric MOSMIX data of Deutscher Wetterdienst, posting cloud and GHI data)

In a couple of months I’ll probably compare the forecast quality - but it’s already now obvious that most likely, this will shame the standard weather services … :slight_smile:

The script uses pysolcast library - big thanks to @mcaulifn!

Have fun, Stefan


I’m now using the above mentioned module (which has received a better description) to implement forecast based charging of a storage battery as well as to interrupt BEV charging early enough such that the battery still gets full with remaining PV power.

The forecast precision of Solcast is just too amazing to not make optimal use of it :slight_smile:

More details here.

Have fun, Stefan


Documentation is great


Oh, I should have read about this earlier :wink: - here’s my approach for SolarEdge inverters to implement forecast-driven charging of the battery. It also tries to empty the battery before/during times where the panels are delivering their peak energy so that ideally no capping kicks in (required by law in Germany at 70% kWp capacity). And I agree, the SolCast data is much more reliable than the one from German DWD for example, especially if there is a change of weather during the day, but I still implemented the ability to use DWD forecasts as a fallback or in case SolCast starts to discontinue the (free) usage of their serivces for private users.

Here it goes:

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