Confusing predictions and freezing charging cost

[jieronymides]

I'm hoping someone can help clarify the below. I've enjoyed setting this up so far but feel likes it missing some optimisation.

My plan for today shows it freezing charge pretty much all day. I don't understand why, it did this yesterday and the sun shone more than presumably expected which meant my battery topped up from solar and I ended up exporting at a lower rate than I paid to fill the battery earlier in the day. Wouldn't it be more efficient to not freeze the charge and then pay to top up the battery later in the day if need be? Considering the import rate is the same at 9am or 3pm.

Second issue:

My load in the evening is consistently as below, this is when I go to bed and the HP turns off so use is always low:

But the plan for the day is always predicting that I have higher use even though I've never had higher use in this time period:

Hopefully this is the right forum for questions like this - thanks Jamie

[gcoan]

My plan for today shows it freezing charge pretty much all day. I don't understand why, it did this yesterday and the sun shone more than presumably expected which meant my battery topped up from solar and I ended up exporting at a lower rate than I paid to fill the battery earlier in the day

Predbat freeze charges when your solar is predicted to be lower than your house load (as seen for most of today) and Predbat wants to preserve your battery to be used when there is a later higher import period.

Freeze charges means the battery can charge, if solar is higher than load, but battery can't discharge - SoC is frozen.

Your import rates increase at 4pm and that's when predbat starts releasing the battery.

Charging from solar is cheaper than exporting and re-importing later on.

[jieronymides]

Yeah that does make sense, thanks. I guess it can't factor in higher solar than expected on the forecast.

[gcoan]

But the plan for the day is always predicting that I have higher use even though I've never had higher use in this time period:

well that's what predbat is predicting. You haven't shared details of what your config is, whether you are using load ML or days_previous, what is in your load sensors, whether you have in day adjustment turned on, etc, but Predbat doesn't usually make up house load so there will be something in your config that is causing Predbat to predict this evening house load.

[gcoan]

days_previous isn't used when load ML is turned on, load ML builds an AI model of your house load based on historic data up to load ML days max.

Have a look at the load ML charts in the predbat web interface, its sometimes easier to view than the load per slot in the plan.

You'd need to look at what is actually in your load_energy_today sensor over the last week to see if the prediction in load ML matches history
have you turned in day adjustment off as per the docs if you are using load ML as this can double count

[jieronymides]

Thanks for your advice. If days_previous isn't used, do I need to comment it out completely or set it to 0?

switch.predbat_calculate_inday_adjustment was set to TRUE, I have changed to FALSE.

I'll see how I get on, cheers.

[gcoan]

you can leave days_previous as it was, so if you ever want to disable load_ml forecasting its easy to revert to the previous load forecasting, or you can just comment it out/delete it from apps.yaml. Likewise days_previous_weight. Leaving it in does no harm, it will be ignored

I just looked at my own predbat, and for all the people I've advised to turn inday adjustment off, I had mine turned on ! Oops

[jieronymides]

Haha oops. It looks like turning in day adjustment off fixed the problem. The prediction is how I'd expect it to be for the rest of the evening now.

Strangely a couple of time slots are showing a random number with a $ sign but looks like its only for today so fingers crossed that fixes itself for tomorrow. Thanks again for your help @gcoan

[gcoan]

Strangely a couple of time slots are showing a random number with a $ sign but looks like its only for today so fingers crossed that fixes itself for tomorrow.

RTFM https://springfall2008.github.io/batpred/predbat-plan-card/#understanding-the-predbat-plan