As some of you are aware, the solar calculation for winter season (in Northern hemisphere) was significantly underestimating.

We have revamped our in-house algorithm, and it now starts from base PV out max, calculates the optimal bell curve between sunrise and sunset, and then applies correction factors for things like sun angle, latitude, panel orientation, roof angle, cloud cover etc.

We know some of you are currently counteracting this underestimation by increasing your PV capacity.

Please change this back as soon as you can, as this change will be rolled out and effective this afternoon (UK time), 16th October 2023.

My actual production today was 13.5kWh against a prediction of 8.8, but the prediction was certainly better than I've seen before in my short time using Wonder Watt, and it turned out to be just right as my battery reached 98% charged at 4pm, which is just what I wanted.

    alunmw
    Similar 7.5 kWh predicted (after dropping kWp to the real number), in reality 11.5 kWh produced

      Is it possible to run the prediction and set command a couple of hours earlier (or have the option to) so that it can be viewed at a sensible time?
      I suspect that it would make very little difference to the solar forecast or battery % effect if it were to be run at say 22:00 rather than the 00:05 (in my case) the following morning, it would then give the opportunity to over-ride the auto setting if needed based on local knowledge.

        SilverArt Would require some rework to allow this, as the timings now are deliberately set as close to the period as possible.

        Maybe some sort of separate 'dry-run' insight without actually setting it makes sense yeah. So people can check a few hours in advance. And untick 'Enable Smart charging' if it suited them.

            admin I think that a 'set alternative' would be advantageous, especially if it deselected after being run at run time as the user wouldn't have to remember to 'Enable Smart Charging' the next day..
            The 'challenge' with un-checking smart charging is that the user then has to go into Givenergy and set what they want. rather than just setting it in WW.

                SilverArt Hmm. On which basis would you make this decision? Ie. when would you use this? The main point of course is that you shouldn't need to. :-)

                    admin When I know the WW forecast is good enough for normal circumstances but I also know the next day is going to be a really heavy use day, family arriving tonight, seven for a cooked breakfast in the morning etc. then another six for lunch which says I should fully recharge charge tonight rather than just getting a nominal small top-up.

                        SilverArt Right, you can achieve that now, by simply modifying the minimum charge percentage, which ignores and overrides the optimal calculated percentage.

                        I'm hoping that helps you for the scenario you're describing?

                            admin I know I'm lazy, but that means I have to remember to reset it, however,
                            if they are here for a few days I wouldn't need to worry about setting it every day!
                            No big issue but I think that it would be a user friendly addition.

                                SilverArt Yeah fair enough, mind you, you could forget you got the family coming over all together! 😉

                                Was just conscious I understood the requirement, thanks for clarifying!

                                  6 days later

                                  Well, a few days results, actual generally below forecasts but much better than before, have all been good enough to make sensible overnight charge decisions so far. Day 6 I went for 100% charge and ended up exporting 2kWh, rest of days shot for 80% overnight and on the backed off the charge rate to spread the charge time.

                                  Solar Act. / Solcast F/c / WW F/c
                                  3.39 _,./,. 6.54 _,./,. 5.1 _,./,. WW set back to 6kWp
                                  5.68 _,./,. 7.52 _,./,. 8.8 _,./,.
                                  8.47 _,./,. 13.67 _,./,. 12.9 _,./,.
                                  8.35 _,./,. 7.66 _,./,. 9.4 _,./,.
                                  13.44 _,./,. 20.5 _,./,. 23.8 _,./,.
                                  7.97 _,./,. 9.9 _,./,. 6.5 _,./,.
                                  12.31 _,./,. 17.87 _,./,. 15.3 _,./,.
                                  7.5 _,./,. 9.31 _,./,. 10.01 _,./,.

                                  8.02 _,./,. 13.48 _,./,. 9.8
                                  UPDATE Lowered WW Solar kWp to 4.5 (rom 6 - This is a slightly north facing E/W split)
                                  9.23 _,./,. 8.45 _,./,. 8.9
                                  1.92 _,./,. 4.17 _,./,. 3.8
                                  10.77 _,./,. 12.65 _,./,. 13.6
                                  6.8 _,./,. 6.82 _,./,. 7.2

                                  This is now close enough to be useful.

                                    9 days later

                                    admin Updated info in prev. post. Reduced WW kWp to 4.5 from 6.
                                    Repeat plea... The one thing that really would be very useful would be the ability to change the charge rate morning and evening, I could then just leave it to run without me baby sitting it.