This indeed appears to work ok, thank you! Now that DESS plans to cover daytime tariff-time with energy bought during night time, it surfaced an issue where small increases in demand cause the battery charge to run short. I think it may be partially caused by increased demand and decreased solar output due to fall/colder weather. I believe some sort of DESS “charge reserve” would help (plan to end day with 20% instead of 0%). But that’s an issue for another topic.
This is indeed a much-discussed problem. But if I look closely, the DESS already includes a 1% reserve. I’ve always been a proponent of such a consumption reserve. But what happens if the system then stores more expensive purchased electricity than needed, when cheaper opportunities arise the next day? Then there will be a barrage of criticism again.
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I understand your point. Good to hear there is already a small reserve, so it should not be too hard to make it configurable. I bet different electricity price/transfer tariff models benefit from different amounts of reserve. In our case, more reserve than 1% is preferred for sure. If the user is allowed to configure it by themselves, there should be less criticism.
I also see that our system rarely uses the full battery capacity. This makes it even more interesting to have some reserve.
Could we at least try this as an advanced feature, Victron? 
I don’t know if it’s a coincidence, and I find it hard to believe. If I set the minimum SoC to 15%, the day ends with 16-17%. But everyone can observe this for themselves. Therefore, I assume that the DESS calculates a certain reserve. Whether this is actually the case, only Victron can probably say for sure. What I consistently observe is that even if the DESS has calculated incorrectly, it tries to find the most cost-effective solution in the next hour. This flexibility is one of the system’s greatest advantages.
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Same here, DESS schedules towards minimum SoC + 1%
That’s a start. Let’s see how this develops.
Thank you so much for this feature! Have been waiting for this ever since launch of DESS. With a couple of days testing behind, everything seems to be working as it should!
With night/day rates for transfer fee and current market price fluctuation in the Finnish electricity market, this feature has completely changed the operation of my system in a good way!
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In the Netherlands, I’ve seen plans for a summer and winter schedule. Does this mean I’ll have to adjust the formulas for all my clients twice a year? Could this be managed with NodeRED, so the formulas are adjusted on a specific date? Or can I export the schedule so I can easily import it for each client?
Perhaps it would make more sense if grid fees could be retrieved somewhere per country or region, just like the EPEX rate, so that it is automatically adjusted daily.
Hi Erik,
In de current set up, I am afraid you’d need to adjust it twice a year indeed. In our experience, even the price formula per provider is not the same among users, so we wouldn’t want to enforce dynamic grid costs to all users in a country, as there might be exceptions to that rule.
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Could you please share a link to the source of that?
You have to scroll down a bit to get to the tables.
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