Dess discharging battery

When will there be a discharge button in the VRM dashboard? Today the planned discharge of the battery will start at 5 p.m. today, while (in the case of Tibber) it could already be discharged at 4 p.m., for example. This has to be done sooner because I can only discharge a maximum of 4 kWh (1 phase) with a 20 kWh battery… Now I manually reduce the max charge voltage to 50v in the DVCC at the time I want, and today that is 1600 hours, to “force” the system to discharge at a time I want… and at 1700 hours. I set it back to 57.6v so that the dess “works” as I want again… This way it is more profitable for me to trade.

In addition, an adjustable SOC value should be possible or taken over from the set SOC. because I am of the opinion that the dess works less well with a 1-phase installation because it cannot be discharged “fast enough” to the grid. There is already a keep battery charged button in the VRM dashboard, so I think a discharge button is also possible. and the reason is that I want to be able to decide for myself how much profit (e.g. from 10 cents) I want to sell. and I don’t want to waste my battery cycle for a few cents difference with the purchase price, as is now happening with the formula proposed by Victron…
Screenshot_20241112_110031_Tibber|225x500

by “Force to discharge” you are meaning a forced discharge to grid, or self-consumption (:= “discharge to consumers”)?

to the grid…

As I read it, forced discharge to the grid. I thought Venus OS version 3.33 had that function (sell and buy button).

could you add a screenshot of DESS’s energy schedule for the day of the tibber-screenshot?

You can setup the maximum discharge / charge current in DESS, so it should actually be well aware that it cannot sell “15 kWh” per hour.

I mean the schedule DESS is creating, including forecasts (:= plan):

Along with prices best case:

then both together most likely start to make sence.

i am not using dess at the moment anymore. i load my batteries at night with ess scheduled charge levels active…works better now,especially since we have almost no sun outside for days now…
and only when the price is high enough on tibber,i sell to the grid manually…

but that’s not why i bought this system…

So if you’re not using DESS, then go back to Venus OS 3.33 or 3.34 large.

Ok, so if you are not using DESS, then your simplest way would be to set a highly negative Grid-Setpoint when you want to sell.

i.e. set it to -3000 Watts or whatever your battery / inverter is capable of.

But I don’t understand the relation to tibber prices - I’m not aware of how it works in Netherlands (?) - for us in Germany, purchase prices are in no way related to feed-in prices. (But Germany is an ancient dinosaur when it comes down to dynamic pricing anyway)

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This is Tibber Netherlands today:
I have the same price for buy and sell.

as shown in the picture, dess fills up the battery to 100% prefer, keeps it here the whole day…and sells at it’s set time later in the day…
in between those hours there is almost no solar,so the power taken from the grid between those hours is extra cost. it should calculate how much you are gonna use that day and release that amount from the battery,and sell what is left in the battery.

Hi, I’m also only using my Victron ESS without the DESS (DESS = out), and I’m also able to manually CHARGE the battery (45kW) with my 3x MultiPlus II (3x5kVA) by the Remote Control setting and activate the “charging timer”. That works fine. BUT where/how can I set a highly negative Grid-Setpoint when I want to sell/DISCHARGE my battery to the GID? Currently I’m not a NODE-RED user, so automation will be for the future, but now I’m searching for a DISCHARGE option/button/timer to discharge/sell electricity out of my battery to the grid. Thank you for your help.

Hi, I’m also only using my Victron ESS without the DESS (DESS = out), and I’m also able to manually CHARGE the battery (45kW) with my 3x MultiPlus II (3x5kVA) by the Remote Control setting and activate the “charging timer”. That works fine. BUT where/how can I set a highly negative Grid-Setpoint when I want to sell/DISCHARGE my battery to the GID? Currently I’m not a NODE-RED user, so automation will be for the future, but now I’m searching for a DISCHARGE option/button/timer to discharge/sell electricity out of my battery to the grid. Thank you for your help.

There is no button in Venus to discharge to the grid.
You have to use Node Red for that.
A simple flow could look like this:

That option is in the ESS-controls of the system:

If you just set that to -2000, the inverters will start to feedin “enough” to cover your loads AND ensure 2000 Watt is feedback to the grid.

Solar present on AC will change that ofc. If you have 3000 solar beeing produced and 0 consumption, a -2000W setpoint will cause the inverters to actually charge 1000 Watts, allowing 2000 Watts of the solar-inverters to flow to the grid.

Hi Ton, many thanks for your Node-Red example to discharge the battery to the grid (= sell). I have tried to create my 1st Node-Red flow over the last 30min, but it is hard without the details (set-up) of every node. And where can I find the “ESS Grid set-point” in which node? Can you send me the example flow in Node-Red (to copy/paste so I can see the detailed set-up of every node) and also how/where to find the “ESS Grid set-point”. Hereby I send you my 1st creation of the Node-Red flow look alike without details. I’m a beginner, but I use Homey and Home Assistant flows as well, so with some practice, I will be more experienced. Thank you for your great help. I feel positive that after >3 months, finally I will be able to also discharge my battery to the grid (sell) and a certain, desired time.
Olivier

Hi Dognose, many thanks for your help and explanation. The GRID setpoint (Instelwaarde stroomnet) is indeed a simple option to change, when I would like to discharge my battery manually to the grid (= sell). I will try tonight for the 1st time, because now it is sunny and I’m automatically discharging to the grid because my battery is full of PV-production. I have a dynamic electricity contract and I would like to prevent to inject or discharge my full battery to the grid when the prices are very low or negative (= it cost me money to inject electricity). I was NOT able to manually sell/inject or discharge my battery to the grid when I want. So this idea, your info, would be a great help already.
For the future, I would like to automate the sell/discharge of energy by Node-Red (or in Homey if the the Victron ESS GRID set-point can be read and changed) by the actual SOC % of my battery, the daily, dynamic electricity prices (I do hope we can set-up the dynamic buy and sell electricity prices in Node-Red as well) and the amount of estimated PV production of that day. I do know how much electricity I use per day, so if the estimated/predicted amount of PV-production is higher that the (actual known) consumption, and the SOC % of my battery is above (for example 75%) and the actual electricity price (EPEX or EcoPower price) is above (for example 0,20), then I would like to sell/inject automatically max. 10.200W (to not increase my quarterly peak consumption, because this cost money in Belgium).
The print screen shows the set-up of my dynamic pricing formula in DESS (EcoPower formulas), which I have tested but the outcome was NOT what I liked), so I would like to automate my self the injection/sell of electricity to the grid.

Hi,

rename to flows.json and import in node red
flows.txt (14.2 KB)

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Hi Olivier,

Is het gelukt?