Hi, my solarforecast is completely off - ist shows almost 10time more energy per hour then it should. [grafik] I have 20kWp solar but mostly north so the max peak I have ever seen was 10kW. If I take then the irradience forecast of 550W/m2 I might be able to produce ~ 6kWh/h at noon. [grafik] …

Since a few days it seems again stable working [grafik] So also charging from grid works again based on price difference when needed. Realistic 7 days forecast: [grafik] makes sense based on irradiance [grafik]

Yes, for me as well. For about 6-7 days now. Very happy, but I must learn to trust it now… Also very curious to find out what the issue was.

[image] endurance: Consumption forecast works as expected even though it is far more difficult to forecast the consumption than the solar. Well, i have experienced that human behavior (that is responsible for consumption) is more predictable than the weather forecast, but that aside, the fore…

[image] Ersus: I have only one inverter SMA Tripower 15-50 connected to the network and communicates with modbus, updates every second. I am curious how many inverters you all have installed and what types and how they transfer the values to the Victron. This should not matter at all for thi…

i was trying solar.forecast and solcast api’s direct, mind you the solcast free hobbyist version where you can still specify how many kW of panels you have. i have 12kw of panels, yet tomorrow some hours im getting a 14kW solcast prediction. there is no one perfect provider.

I hope to not hijack this thread but I’m currently looking at my forecast and I really don’t understand why it’s forecasting more than I could ever produce, given I only have a 100/50 at 12v, so forecast should know that and cap the production at 700w tops: [image]

I too am looking at my forecast and see the discrepancy. Could it be that server issue reported by victron causing this issue? My solar forecasts have been steady until yesterday when I saw this [image]

Yes, it must be an issue with the estimations, they were steady for me too, and now if I do the weekly forecast it’s overestimating like exactly 2x to 3x, I will ignore it until it gets settled, thanks for your input Cornelius, much appreciated.

Since today it seems to be wrong again. Same here for today but for tomorrow it is the opposite (with the same solar irridiance forecast). [grafik] But also price display for tomorrow looks weired. Looks like they are patching VRM currently. DESS solar forecast looks ok but price curve looks str…

It got fixed at my end, amazing response times, thank you! Edit: weekly forecast is still broken, estimating my next days as +8 kWh, as you can see 2.51 kWh is accurate for today, if I see individual intra day charts, they are ok. [image]

DESS: Why is the forecast 2-6 times higher sometimes - how is solar forecast working?

Q&A and troubleshooting DESS

endurance 7 August 2025 15:54 92

For me since this afternoon looks okish again

weekly looks a bit to pessimistic but I dont care as long as the forecast is OK the evening before latest in the early morning

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DESS: Why is the forecast 2-6 times higher sometimes - how is solar forecast working?

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