I had a look at your system and the 26th February:
DESS bought the energy in the night, because it expected way higher consumption between 7 and 8. But this day, there was not much consumption. Then the selling happened instead.
As far as I know this is caused, because the scheduler does not track actual purchase-prices of the battery content (beause this could lead to deadlocks, when buying is expensive before next day prices are known and then you have days of cheap prices). So, what the scheduler does instead:
If you have selling to grid enabled and have more energy in the battery than needed âat sunriseâ, it will sell excess for the most expensive hours before sunrise.
Usually that works out fine, because energy in the battery is either deferred solar - or it was buyed cheap enough with the idea to be sold (hence the margin was expected at buy time) - just energy bought for consumption that finally didnât happen - is unideal and may cause what you saw this day.
But, thereâs a BUT:
After the consumption did not happen - selling again was the most economical thing to do:
Your battery reached 100% from solar again this day. (expected)
Selling the energy â7-8â was worth 0.09
If it would have been kept in the battery instead, you could have charged LESS solar later, causing feedin for 0.01, when the battery would have filled up earlier.
This is a typical example situation, where it is important to understand, that making purchasing decisions based on forecasted values could always have 2 outcomes:
Forecasting was right, then the (deterministic) schedule is fine.
Forecasting was wrong (or say: Reality hit different) - then the decision could be wrong and a financial drawback.
(âNot chargingâ despite the forecast indicates a need has the same two options: It could have saved money, or lost money in form of more expensive purchase prices - But acting against the forecast would not be reasonable)
May I file this to my list under the last point " misaligned assumptions based on early developments". That margin was not expected at buy time because DESS isnât programmed to buy speculatively. But that topic is for another day, we have bigger fish to fry first.
No offense Dognose, I hope you know I do appreciate your efforts to help people out with real use cases. What might be helpful here is to start making very clear distinctions between DESS Green and DESS Trade systems, they are very different beasts from a schedulers perspective. And between predominantly Solar versus predominantly Battery use cases, they need a distinctively different scheduling approach to function well autonomously.
Worst case scenario still being DESS Trade without Solar that needs constant interventions, manipulating MinimumSoC or other settings to behave rationally.
Interventions to make DESS Trade behave are hard to automate away without suitable tools (b_goalâŚ). The level of expertise required equals that of developing a private trade engine, which defeats the purpose of having it as an option on VRM DESS IMHO.
That said, today and tomorrow are good money making days, hopefully the flatline price winter slump has finally come to an end, long live price volatility.
No. Because âmyâ favorite DESS topic is not âmyâ favorite DESS topic to begin with. Instead it is, admittedly according to âmyâ investigations, âtheâ most pressing DESS topic (1) affecting âeveryâ customer that bought in to the promises and expectations of the DESS Trade solution. Donât get me wrong here, I do not try to kick against âheilige huisjesâ (dogmas) just for the sake of being controversial. I actually care about the quality of the solutions Victronâs DESS could provide.
And by the way, I have developed a plethora of hacks and workarounds to make âmyâ DESS Trade system perform very well on the day ahead pricing market, it took an immense amount of engineering hours to get there but I succeeded. The reality of that is that âIâ do not need Victron anymore to make DESS Trade work for âmeâ.
But that does not mean I am not sad and disappointed that Victron is showing a consistent negative attitude to cooperate with itâs "frontierâ customers (like myself, nevermind me saying so), to provide a platform friendly that is actually helpful and supportive, for us to help each other on this matter.
(1) And you know I am serious because we have been here before, when I flagged the previous most pressing issue: the TargetSoc Integer precision issue, that encountered the exact same pushback and ad hominem attacks at first, until it got ĂĄnd admitted to be a real issue, ĂĄnd fixed!
Okay, then iâm not âkindly askingâ but requesting you to do so in accordance with the community guidelines:
One Question per post
This community is intended to become a knowledge base. We want people to be able to quickly search for their question, and find the answer. Ideally the answer is a link or reference to the precise Victron documentation.
To help with this, please keep your posts focused clearly on a single question, issue or problem.
Itâs really sad to see how peopleâs feedback and urgent request for changes are handled like this. Why is victron and their sellers so convinced their system is 100% functioning? Because it isnât. But what I see here is what I also experience with the person that came to my house to sell the Victron system. Nice story, but at the end there is not much of a discussion possible with the same person. Spreading the word on Facebook how much you can earn. Not mentioning the losses caused by warmth. And then there is the issue of the system selling with loss. I am really curious what parameters are behind all this.
Also, I really donât understand why it doesnât keep track of the value in the battery. If I can simply have that in home assistent, (I am no technician, just a hobbyist that likes playing with systems, and testing software in the past for work) why cant be this included in Dess?
Why does the system change plans during the night?
In stead of silencing people, it would be better to involve them in improving Dess. And make it a system worth recommending to others. Cause right now, I definitly wonât. The hardware, I guess that is all fine, but the software.. Nah.
Jan, Anita,
even though Victron handles customer feedback poorly, itâs no reason to clutter up threads with altercation.
It doesnât solve anything, youâre just hurting other customers.
If you want to solve it, write to the owners of Victron, buy shares and become an owner, or join forces with the competition and make a better system that will give Victron a lesson, etc.
Dognose,
no, Iâm not saying that youâre doing your job well.
Youâre supposed to deflect/explain bad arguments (youâre doing that well), but youâre supposed to accept good ones and pass them on to process and improve the system (youâre not doing that well).