DESS green mode selling for unknown reason

I have enabled DESS green mode yesterday.
And for today it plans to sell for some reason.
It’s winter and there is no solar so why it sells at all (Green mode should not do this unless you solar production is more than consumption)


And at 18:00 it started to sell???
It seems that it follows the SOC because it overestimated the load and now there is more in the battery than it thinks. And therefore he need to get rid of that energy???

If so then that Green mode is very flawed :frowning:



I have disabled DESS because it is not usable in this way.

Why don’t you disable discharging battery to grid, if you don’t want it?

I can sell to grid and want that system sells sulprus solar to grid in summer time.
And it is cheating when I disable it in winter. System should know that selling to grid in winter time with “green mode” is not allowed, period :slight_smile:

And there is no clear explanation why system decided to sell from battery to grid in the first place?
I do not see any reason for that

These are two different settings!!!

I also sell PV surplus in summer:

But I don’t sell from battery to grid, see screenshot above.

These two settings in combination with dognoses Hack will do what you want (so I think)

I already have “charge battery from grid restrictions” enabled. So I can not enable “discharge battery to grid restrictions” at the same time :frowning:
Today morning for testing enabled dess again and it started to export.

But can someone explain why does my DESS want to achieve the situation that battery is at minimum SOC at the end of the day???

Why?

DESS only plans as long as prices are known and tries to get by without using the grid until then. The rest is sold to make profit.

In the morning, prices are only known until 23:59, so the battery is used until then to supply all loads. The rest is sold as long as you do not disable discharging the battery into the grid.

As soon as the prices for the next day arrive in the afternoon, a new plan is made. The planning for the evening may then look completely different.

My energy transportation prices vary from time and weekday.
And as dess does not allow different prices for different days/hours I have eliminated charging in more costly hours/days and only allowed in the night when there is the best transportation prices.
My transportation prices lowest is 4 cents and highest is 9 cents.
My electricity price is nordpool and that is managed by dess automatically.

why the hell does it sell in “green mode” this should be in “trade mode”
“green mode” should be so that buy as little as possible from the grid at the best price if needed.

OK, I see. I also don’t understand why Victron only allows us to deactivate either charging from grid or discharging the battery to grid and not both together.

Perhaps this would be possible via Node-RED with the victron-vrm-api. You can also adjust all DESS settings via Node-RED. You could try this.

https://communityarchive.victronenergy.com/articles/293324/node-red-vrm-api-and-dynamic-ess-1.html

The problem is that DESS predicts a target SOC and refuses to divert from it. For example, the target SOC was 80 yesterday, but before the hour was over, it has already reached 80 and there was still excess solar energy. Instead of putting it in the battery, it just sold it, even when on green mode.

This is prevented by dognose’s hack

But in my case there was no solar at all. It just wanted to sold it. And I assume the same that it overestimated that I will use more consumption. And if the real soc and calculated target soc difference were too big it want’s to sold it.
What I do not understand is why does it not recalculate the soc every hour and take account the current soc.
Then it will not drift away from the real life values :slight_smile:

I configured DESS that it can not sell to grid and now tomorrow looks like this


But as I do not like it then I will use my own node-red implementation that will use GridSetpoint and will charge around 30kWh from the grid (some of it will go to direct use and some of it to battery)
Lets wait and see what DESS will think of it tomorrow morning then :slight_smile:

It seems somehow DESS managed to disturb my gridsetpoint. From 01 to 2:30 system did not charged the battery.


My gridsetpoint was correctly set

So it seems DESS restricted inveter battery charging.
Does someone know where I can see that afterwards?

DESS is to make money form charging and dis charging from the grid in combination with PV power. It also try’s to estimate you home load behavior which wil be done (I think) by doing trend analysing the home load. So when i follow a strick schedule of the day every day of the week and that erery week of the year, It wil do it the way you would like it to do and eurn money for you.

If how ever you are not follow a strick schedule al of the day’s than you will mess up the estimate and it wil never know exactly what wil be needed at which hour of the day. So whenever you want you plugin something, start doing things like laundry or the diswhaser. some time you will do this in de morning somtimes in the evening and than some day’s of the year its estimate will be wrong and you buy some at an expenencive hour. You can’t make this last view pennies. even if you would do the estimate your self you will be of somte times, because you do something els than planned.

I understand that, but I have EV that I charge irregually with Victron own EV charger. So DESS should count this out of predicted consumption.
For example in the workdays when I’m at work during the day I charge with 4kw during the night from house battery to EV battery.
But weekends I preffer to skip that PV AC->Bat DC → EV charger AC conversion and charge with EV charger auto mode directly from PV.
And for example I could see yesterday that today night it thought that I will charge in the night. And as I know that it would start discharging to the grid in the night when DESS excptected load is wrong I disabled DESS in the evening. Actually electricity selling price in night and morning was 0,01€ (my battery cost is 0,03€ so DESS would made me -0,02€ cost)
And in the morning I enabled DESS again and it started to discharge to grid so I had to disable it again.
I know that DESS does not know that I itended to charge my EV during the day. But Victron knows my EV charger and should exclude it from load, because it is irregular.
Also if there would be some parameter I could restrict selling from battery to grid below some price, then I would enter there 0,1€ and all these situations would be solved. Because when battery is full and surplus will go to grid then that does not cost me 0,03€ battery amortization :slight_smile: