Fully agree on the 10ct margin rule for running trade mode.
Trade Mode with less than 10ct margin between buy and sell (or actual profit per kWh even) would (figuratively speaking) boil down to just watching your batteries slowly disintegrate.
While this can be very interesting as a hobby project, it makes little sense economically speaking 
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Hi Jan,
been following your work. I just commissioned a large solar install with 90 kWh battery, a 12500 W 3 phase grid connection and a 18 kW array. would love to try out your version of DESS. Are you still looking for people to test?
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I’m reluctant to proceed developing that solution because I identified a mayor function regression in the VRM DESS Trade Mode implementation that I cannot get the Victron developers to address.
The function allows to set a SoC target at a specified hour using the b_goal_SOC and b_goal_hour settings. These settings are still available in the Node-RED DESS implementation (and even in VRM-API) but is ignored in VRM DESS.
Victron consistently refuses to discuss the issue, workarounds or alternatives and even worse Victron’s on the record position is that both this function as well as Node-RED DESS itself are scheduled to be phased out.
In less than a year I have spend a thousand engineering hours to familiarize myself with the Victron platform, it’s abilities and it’s quirks, interact with the community and Victron’s staff to develop and test a DESS Trade-only system that works real well for our system. But our solution relies on the ability to instruct the scheduler what the best time of the day is for the batteries to be full. Without that ability DESS Trade cannot be made to work in a reasonable autonomous fashion, no matter how it is implemented, something needs to be done to fill the batteries before a certain hour of the day (dinnertime has been working great for months in a row now).
As long as Victron keeps ignoring the reality that (VRM) DESS Trade, as-is, is at best severely handicapped and at worse completely broken, I have little motivation left to spend time on this issue.
I have been running in DESS green mode for some time now and must say that I’m reasonable satisfied with it now. I see it tries to get a full battery around 19:00 hours or so and then discharges around 20:00-22:00 depending on expected solar intake for the next day. I also play with node-red a bit but only to get status info and graphs, and I used the VRM-api node to set the SOC goal at 100% at 19:00, so maybe that helps in above observation…
The only thing that still worries me is the period balancing setting. I regularly see
In the morning but later such days the message is gone and no balanbcing takes place….
Any ideas how to figure what i do wrong here?
Do you use the API to manipulate minimum SoC?
If so be aware that doing so completely disables the scheduler, in effect setting minimum SoC to 100% is the same thing as setting ‘keep batteries charged’.
In my opinion this is putting the horse behind the cart, fixing post scheduler what should be fixed pre-scheduler. That is why I have been advocating for a true ‘target SoC @ hour-of-the-day’ port of the ‘b_goal_SOC / b_goal_hour’ function still available in Node-RED DESS (advocating without success, in contrary)
jan, I’m using the node-red VRM API node to set b_goal SOC and b_goal hour, but am not sure if it has real impact.
this is my schedule for to day at the moment,using green mode.
I have no idea about Green mode but in Trade mode setting b_goal values surely does not work for the VRM schedule pushed to the MultiPlus II ESS assistant. Should be easy to test though, set 100% at any hour of the day (other than where the green mode currently targets a full battery) and check back when the next schedule comes in, few minutes after the whole hour usually.
For those so inclined, you could also check the differences in the schedule object as output from the VRM-API call for setting those settings and the call for installation stats. We recently discovered that those differ, use search for the details.
Then again, another surprise: why dump battery between 15:00 and 17:00 during ralatively low prices periods, while thre are enough oppertuneties to do that later today… Now it discharges and charges the battery within the same hour. Not very efficient…
Same strange things I see also with the DESS, it going to use power from the grid at the most expensive moment of the day, at an hour later it will sell when it is less profitable…
And there it is: 15 minute pricing will activate tomorrow october 1st for Tibber NL (see the link below mentioning ‘whole of europe’)
- Is everybody aware? And ready?
- Will Node-RED DESS still work?
- Will our custom flows still work?
- Is Victron aware and standing by to assist?
Or will most be taken by surprice leading to a flood of DESS related messages come tomorrow? Time will tell.
Van uurprijs naar kwartierprijs | Tibber Magazine
I tried to switch to 15min pricing today but it completely messed up my DESS, so I guess I will try again tomorrow?
Not sure if this would be the right place to add my varying results with Trade mode DESS but let’s see if it can be explained or helps out further DESS development at Victron. What I see right now is that the system is dumping the battery to grid although I don’t see a reason to. Battery is not full and according to the charging strategy it is not on par with the forecast. Price is still very low so there’s no gain. Even worse, 15 minutes later it stops dumping to the grid and it’s charging the battery again from solar energy. 
It’s not the biggest problem in the world but I would at least like to understand the decision making process behind this.
DESS (Trade) falsely assumes the presence of plenty of solar power in relation to the available battery capacity. Therefore it’s strategy is fully biased towards maintaining a minimum SOC level. This completely fails to recognize any and all systems that are primarily Trade focussed, in extreme large battery capacity systems wihout any solar production at all. The latter being much better served with a maximum SoC biased algorithm. Node-RED DESS allowed to tailer for those systems by setting a ‘Scheduled SoC at a scheduled hour’ within the ‘known prices timeframe’ but for reasons still unbeknownst, Victron ignorred all pleads to implement (port from Node-RED DESS to VRM DESS) that scheduling input setting to VRM DESS.
Indeed, we really would be helped with a strategy that is focussed on max SOC, reaching at end of the solar day a SOC close to 100%. I have DESS green mode and have many times the issue that all my solar is ‘sold’ and I need to consume from the grid, whereas there was sufficient solar to cover the day needs
see here (and many past posts concerning the same topic), hopefully it will get some attention this time round:
I asked @dognose about this as well, if you were curious. DESS not scheduling 100% SOC in Green Mode
DESS Trade is doing interesting things again. It is supporting own loads below TSOC, and plans to buy the energy back during the next hour, and sell it later. This makes no sense considering system losses.
15 minute pricing instantly quadrupling DESS quirks in action.
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So now it continues with self consumption, and has used so much it only has one hour of selling time possible, where previously it had two. I suspect it won’t end up selling any, but let’s see.
Seems pretty broken TBH.
If you want to avoid this, you should set the battery costs a little higher
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