As well as kWh yield and daily usage, the calculation also takes into account the current SOC of the battery, which is why you are seeing this.

    admin I'm still not convinced, I don't reckon the second example would had covered the day, and the third example was more than extremely well covered. Had the the first one come in at 90% to 95% I wouldn't have given it a second look.
    I'll keep my eye on it.

        SilverArt Fair enough, we’ll also run some more tests at our end and create better test coverage for multiple scenarios.

        Will let you know the outcome.

          10 days later

          I have noticed the same issue. When the battery is very/fully depleted a charge level will be set for 100%, even if the solar forecast for the next day would be enough to cover most of my specified usage. This has resulted in starting a sunny day with a high level of charge, filling the battery by mid-morning and exporting the excess at a loss.

            Avenir Can you give us your example please and when this occurred?

              2023-11-11 00:20:12 4 % 8.0
              Charge instruction set: 100% target at charge rate of 79%

              2023-11-07 00:20:42 4 % 8.4
              Charge instruction set: 100% target at charge rate of 79%

              Battery 9.5, usage set to 12

                Avenir I'm guessing GivEnergy setup with the 9.5 reference? Also why a loss?
                In my case I've come to the conclusion that I should always charge to 100% as import costs me 9.5p/kWh and I'm paid 16.5p kWh for export.
                That then makes me wonder if I should just leave my 'Charge Power' at 1900w and see how it gets on (5.2 + 9.5 batteries) rather than fussing about it.
                Why 1900w - The inverter and the battery temperatures stay lower than when charging at 3000w, and would get me to at least 90% in the morning, which I could boost if needed.

                    Avenir The difficulty is how much value to attach to lower end kWh predictions. It's possible for us to tweak it, but there is also a danger of you ending up needing to pull from the grid at peak rates.

                    Easiest would be to reduce your average usage and see how you go.

                      In the examples above, the battery is charged to 100% even though the forecast is for uninterrupted sunshine (the forecast values are the max achievable In winter for me). If the battery was at a higher state of charge it would charge less. For example:

                      2023-11-25 00:20:58 38 % 7.7
                      Charge instruction set: 80% target at charge rate of 36%
                      (I have set a minimum of 80% to reduce the risk of undercharging)

                      It does look like when the battery is fully depleted at 4% the forecast is ignored and the battery charged to 100 regardless. Because this behaviour is inconsistent with normal operation, it makes it hard to correct for by adjusting usage amount.

                      SilverArt it’s a loss because I import at 9p and export at 8p (excluding conversion losses)

                        I'm also puzzled now. I did not change anything to my settings for the last week and I observe the following:

                        On 28-11 I have 19% SOC and solar forecast is 14.0 kWh --> charge to 100%
                        On 01-12 I have 13% SOC (less than on 28-11....) and solar forecast is 12.9 kWh (less than on 28-11) --> charge only to 34%

                        That doesn't make sense at all. @admin Did you change anything in your formula's over the last few days ?

                          JMA Nothing at all has been changed. You can know by the version number, we’re still on 0.3.135.

                          You’re right though, looks a bit odd.

                          We’ll try and get to the bottom of this today. Will keep you posted.

                            JMA Hang on, you are misreading what happened on the 28th with the action on the 29th.

                            Looks like the 28th it didn’t charge at all as the values were above the threshold you configured to use the battery.

                                admin
                                Sorry - looked at the line above instead of below and I was not drinking...

                                  admin I must admit to having misread the info in the past. The challenge is the lack of consistency with the colours v the information content. IMO the Date rows should always be the same format. Possibly the detail rows should also be inset slightly.

                                      SilverArt Yeah, that’s a fair comment, the idea was to make it easier to group them.

                                      We’ll have a look. Thanks.

                                        OK, updated activity log display available now in v0.3.137. Thanks!

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