Feature suggestion: battery headroom

[psimonkey]

Feature suggestion: battery headroom

[springfall2008]

If you set your inverter_limit correctly (this is the max AC limit) then this is all taken into account. Predbat optimises for cost so if it's cheaper to charge the battery less for the above reasons then this will be accounted for automatically. Do you see cases where this is not happening?

[psimonkey]

I see. I think this is showing some clipping today:

And here's an example from a few days ago of excess going into the battery when it had a bit of room:

But I'm not sure that's definitive - I appreciate the predictions are never going to be perfect. How does it know how much surplus is possible, there's no parameter for PV size? Does it base that on the Solcast data?

[springfall2008]

The sim isn’t to avoid clipping totally but to end up with the lowest cost outcomes taking into account the risk of bad weather as well.

the PV generation predictions come from Solcast

[psimonkey]

Probably worth mentioning that a headroom feature is probably only really useful with the Flux tariff. Leaving headroom in the battery is quite safe with Flux - 1 kWh less charging in the morning saves 20p of import, and means you miss out on 20p of export around midday. If the weather's bad then a bit of extra import at 30p during the day or lost export at 30p in the evening isn't much difference. With other tariffs where the difference between cheap import and normal export is larger, it's probably not worth the risk. You've already got the best_soc_min setting (which potentially increases cost), so would a best_soc_max be reasonable?

[springfall2008]

Sure, I could add the feature for the next release if you think it’s useful

[springfall2008]

Please see the latest release:

https://github.com/springfall2008/batpred/releases/tag/v6.8

[psimonkey]

Great - cheers. I'll give it a go and feed back.