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Dirk-Jan Faber (Victron Energy) avatar image
Dirk-Jan Faber (Victron Energy) posted

Dynamic ESS: Green mode

Hi community,

We’re excited to introduce a new feature on VRM Dynamic ESS that makes Dynamic ESS more flexible for different use cases: Dynamic ESS Green Mode. This mode is designed to prioritize self-consumption within your battery system while ensuring surplus solar energy is fed back into the grid. Here’s a breakdown of how Dynamic ESS Green Mode works:

  1. Optimized Self-Consumption: With this mode enabled, your system first directs solar energy towards meeting your immediate consumption needs.
  2. Battery Charging Priority: Once your consumption needs are met, any excess solar power is utilized to charge your batteries, ensuring they are charged sufficiently for hours without solar.
  3. Grid trading: Only after your consumption and battery charging needs are fulfilled does the system consider selling surplus solar energy back to the grid.

The aim of Dynamic ESS Green Mode is to maximize the use of renewable energy within your own setup before considering energy trading, promoting greater energy independence and reducing reliance on the grid. To explore how Dynamic ESS Green Mode can benefit your setup, navigate to the DESS settings and enable this feature.The current mode of Dynamic ESS, trade mode, will still be available. Trade mode considers the economic benefits of selling to the grid versus self-consumption. In doing so, if selling back to the grid is more profitable than charging a battery, it will opt to feed back into the grid. Whether you choose Dynamic ESS Green Mode or Trade Mode depends on your priorities and economic considerations. Both modes offer unique benefits tailored to different user preferences and scenarios.

You can find it in the Dynamic ESS settings under the system section.
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We encourage you to experiment with both modes and share your experiences with the community!

Also, when running Dynamic ESS, please make sure to either update to v3.31 or to run the latest candidate release, if you haven't already.

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ronaldt avatar image ronaldt commented ·

Thanks! Another nice step forward in the functionality. That is what this system makes great. Constant improvement and good feedback from an active community that helps to improve the product.

I have used Green Mode already a couple of times via Node Red. But my first point of improvement would be to at least sell back to the grid when the price is high. That is not happening now. See graph below where the system sells just after the peakprice. And this has happened more then once.

Where Green mode is sort of trying to have my batteries full and only exports to be able to store my solar energy expected the next day in the batteries, trade mode is trying to sell/export all my energy. So we go from one side of the spectrum to the complete other side. It would be nice to have a sort of aggressive factor in the system. Where you can slide between Green and Trade mode. I do not want to trade a lot to only gain a few cents, but I have no real control over that now.

See below the example where at 19 and 20 price is maximal, but export only starts at 21. Batteries were already completely full at 19.

schermafbeelding-2024-04-29-om-134035.png

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Johan avatar image Johan commented ·
Hi to all,

Greenmode is nice a big improve, for me at least. But it would be nice, that the system still could deliver back to the grid when the price from grid is high, and soc is above a set value.This will be useful in summer when batteries are full from solar. In the evening / morning empty batteries when price is high, and overday charge again.

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ojack avatar image ojack commented ·

Thanks a lot! Green mode is exactly what we need in Germany.

Next winter will show if charging from grid at lowest price as much as necessary and as little as possible will work too.

Three improvements come to mind:

1. Charging slowly if PV forecast is much higher then consumption forecast to protect the battery by means of lower current and less time idling at 100% SoC. These day battery is full at 9-10 if not reducing the current.

2. Some kind of advanced battery life which only charges to for example 90% (user defined) all day if sufficiant. And charging to 100% once a week for balancing.

3. Prioritizing battery charging over mppt because of better efficiency. Up to charging only via mppt if the solar forecast DC is sufficient for reaching target SoC until maybe early afternoon.


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electronicsuk avatar image electronicsuk ojack commented ·

I think #2 is already being worked on by Dirk and the team. I don't agree with #1. Priority should always be to get batteries charged as soon as possible in green mode, because you don't know if the PV and/or consumption forecast is correct, so better to have plenty of charge 'in the bank'. If you're worried about battery life then you can always set a charge current limit to apply at all times.

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frantiseksobotka avatar image frantiseksobotka commented ·

Hello,

that is great news. We expected step forward already long time.

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So let's test it!

Can you please later share more details about all new adjustment of the system for the green mode?

Is there also any modification for the trade mode?

I just switch on green mode. The planning looks fine, tomorrow trying to fit a single point to 100%. What I see also that now at evening it follows also my ESS grid set point -200W, is that right that grid set point is considered by DESS already?

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ronaldt avatar image ronaldt commented ·

When switching between Green mode and Trade mode the save button is not activated (Verzend in Dutch). Only when you change something else on the page, you can save the settings.

schermafbeelding-2024-05-08-om-053830.png



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Barbara (Victron Energy) avatar image Barbara (Victron Energy) ♦ ronaldt commented ·

This is a known bug on BETA. Could you confirm that on production VRM you don't encounter the same?

We will fix the BETA bug today.

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grua avatar image grua commented ·

Thank yo so much for this great feature!!!

I'll test it!

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zonnigbreda avatar image zonnigbreda commented ·

first of all: Great enhancement!

I find the first lin of the description in the " Trade Mode" box rather wrong, or at least put you off in the wrong direction.

It suggest indeed you always sell your suplus solar back to the grid, which unless you know the system better , gives the idea that solar is sold directly (e.g. even if the price is negative)


I think the consfusing word is "always", whereas in the desciption in the post it is more nuanced: "if selling back to the grid is more profitable than charging a battery"


Trade mode considers the economic benefits of selling to the grid versus self-consumption. In doing so, if selling back to the grid is more profitable than charging a battery, it will opt to feed back into the grid.


Would suggest to improve the text in the box. e.g. "Sells surpluss solar back to grid if more profitable"

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Barbara (Victron Energy) avatar image Barbara (Victron Energy) ♦ zonnigbreda commented ·

Thank you for this suggestion, I will change the text!

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electronicsuk avatar image electronicsuk commented ·

Hi Dirk. I've been awaiting this for a while. Thanks again for considering us users who aren't paid for export. Sadly, it's still not behaving as expected for me. Switched on Green Mode this morning and my system is exporting even though the batteries are nowhere near full.

I checked the batteries and the charge limit is 240 Amps so there's no reason not to be charging them when there's plentiful PV. Seems like Green Mode is still too concerned about maintaining a set battery level instead of filling the batteries as early as possible?


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Dirk-Jan Faber (Victron Energy) avatar image Dirk-Jan Faber (Victron Energy) ♦♦ electronicsuk commented ·

One of the things I noticed on your system is that you have your PV inverter on the AC output side. Please update to v3.31, as there is a bug in v3.30 that is affected in this combination. I'll update the above post to also mention this.

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eamonpendergast avatar image eamonpendergast commented ·

Nice to see new options rolled out for DESS! I'd like to echo the comments of some, both extreme cases are covered, but there's no middle ground.

In Ireland, there's an unusual Usecase; fixed rates 24/7 for selling to the grid (25c/kWh), high day rates (37.5c/kWh) and highly reduced night rates from 2am-5am (5.5c/kWh).

Other considerations are my peak generation ability is ~11.5kWh, but I'm capped to 5.5kWh when selling to the grid. So if my battery is full and house consumption is low, I'm not able to fully utilising the system.

Both algorithms struggle to manage this well.

With Green mode, looking at the schedule it produced, it basically always charges the battery to 100% as fast as possible and then begins selling back. This risks poor utilisation by hitting against the 5.5 kWh cap when the batteries are full and the sun is out.

With Trade mode, it looks like the algorithm decides it is always preferable to sell to the grid, so the batteries never get charged unless the 5.5kWh sell cap is hit, in which case, the excess goes to the batteries. Other issues with this mode is that it pulls from the grid during periods of high usage (kettle) when rates are expensive rather than using the battery because the Target SoC for the battery hasn't been hit.

I'd really like to see a middle ground where the algorithm charges the battery enough to ensure there's enough to cover overnight consumption - or at least ensured enough charge to get to 2am when the battery can be charged cheaply. The simplest solution would be a setting that allowed me to stipulate 2 items:

- Restrict grid purchase to 2am-5am only.

- Set minimum SoC the algorithm should reach by sundown.

I'm aware I can use the VRM setting (Battery SoC Minimum), but this will switch to the grid if the battery drops below that SoC: I want to set a target SoC for the algorithm but continue to use the battery as long as possible.

Looking forward to further developments of DESS!

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Petr LANDSFELD avatar image Petr LANDSFELD commented ·

Hi, I don't know who should i contact, but i would like to do Czech translation of vrm portal. There is lot of translations, but Czech is missing and in Czech republic is, i guess, big community of victron. Can you help me? Thanks a lot

Petr

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Dirk-Jan Faber (Victron Energy) avatar image Dirk-Jan Faber (Victron Energy) ♦♦ Petr LANDSFELD commented ·

I am the contact person for all of the translations within Victron and Czech translations for VRM is already being worked on. I expect that to be added within a few weeks.

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frantiseksobotka avatar image frantiseksobotka commented ·

Hi to all Victron,

can some of you contact me and help we with this stupid behaviour of DESS. I asked here several times, but not any help or progress at all.

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frantiseksobotka avatar image frantiseksobotka commented ·

Hi gentlemen,

can anybody esplain what the system has in plan tomorrow? What will happend with the produced energy? Ther is blind area in graps. Also in planning is not considered!! Why there is in greeed mode not any charging planed during negative price?

That is really already upgrade of official relase of DESS??? Victron???

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Jeroen Peters avatar image Jeroen Peters frantiseksobotka commented ·

This seems like another case of DESS not being able to deal with negative prices.

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kositch avatar image kositch commented ·

Great! When can we expect the update regarding the possibility to set different price formulas for different hours of date when having Dynamic buy prices? For our country (Czechia) and some distribution taxes it makes big difference in price between hours so it is not possible to use DESS because of that.

Second question - would it be possible to "zero" negative prices (p) when on Dynamic price tariff? Some of providers do not accept negative prices and they calculate the price of (p) as 0, I am not sure it is possible to solve it by any formula. It would be just one checkbox to make all negative prices (p) as 0.

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kositch avatar image kositch kositch commented ·

@Dirk-Jan Faber (Victron Energy) - please any update on this, when will be possibility to set Dynamic price formula for different hours? And is there possibility to make also dynamic price "p" NOT negative - meaning make it 0 when dynamic price drops below 0? Thanks, those two missing features stops me and a lot of other from our country from using it!

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switchinggreen avatar image switchinggreen commented ·

Great! Very nice features.

I would like a option like, buy when soc is xx% and price is € to target xx% soc

And sell solar to grid when target xx% soc is reached

Prices are low this afternoon, but there is no grid to batt predection.

Love your products!

Kind regards,


Jacco Gommers

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guru77 avatar image guru77 commented ·

Hi!

Can I use the trade mode also while charging my car with the EVCS?

I would like to sell as much as possible, but if there is some excess solar power, it should go to the car (my grid output is limited to 4,6kW)

Thank you!




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grua avatar image grua commented ·

@Dirk-Jan Faber (Victron Energy) why did DESS Green Mode buy from grid today at highest price although battery was full, and energy from grid would be much cheaper at night?

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But much cheaper during the upcoming night:

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That doesn't make any sense?

VRM b827eb273733

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Not sure why that happened. Will look into that tomorrow.

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cor avatar image cor commented ·

dess-energie-belastingen.jpgI have a three phase system with 9.6 kW Pylontech batteries with a Solaredge inverter. After sunset, the inverter starts supplying 79W of power and takes the rest from the grid. The graph shows that it alternates between mains and battery during the night. how can I adjust this?dess-energie.jpg

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rikvanwesterveld avatar image rikvanwesterveld commented ·

Hi,
Many thanks for this new feature, running Green mode since last week but wonder what the logic is behind the decissions my system makes...
(I'm running a 3 phase MP2 - 48/5000 / 70-50 system)
Yesterday my battery (30Kwh) was full and system used some of this during the night.
Strange thing is that the system starts to unload when the prices are lowering end of the morning and not during the higher pricing last night (eg. 00:00-01:00)? See graphs below.

dess-15-05-2.jpg


Even now when almost midday, the system unloads to the Grid instead of charging the battery?

ess-15-05.jpgdess-15-05.jpg

Any suggestions why this happens and what I can do to solve this?

Thanks again, Rik

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hans818 avatar image hans818 commented ·


Hi i still see strange purchase , battery almost full, plenty of solar still buying from the grid

VRM: c0619ab4d86f

gr Hans


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sarowe avatar image sarowe hans818 commented ·

Ich denke die Verbrauchsprognose zum Zeitpunkt des Stromkaufs war höher, weil der Verbrauch auch vor dem Zeitpunkt des Stromkaufs höher war. Ein Phänomen das ich auch immer wieder beobachtet habe.

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grua avatar image grua commented ·

I don't understand this consumption forecasts, they are absolitely too high. The last days consumption always was about 14 kWh per day because the heat pump doesn't run any more:

screenshot-20240516-183737-chrome.jpg

But today forecast was more than 20 kWh (already now in the evening it already has reduved a luttle bit). But as you see most hours too high:

screenshot-20240516-183820-chrome.jpg

And tomorrows forecast again absolutely too much, more than 26 kWh!!!:

screenshot-20240516-183833-chrome.jpg

ID: b827eb273733

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sarowe avatar image sarowe grua commented ·

Für mich ist die mangelhafte Verrbrauchsprognose eines der größten Probleme des gesamten DESS. Ich habe es wirklich sehr lange, sehr wohlwollend beobachtet. Aber das ist noch eine große Baustelle. Der Grund warum ich es jetzt erstmal deaktiviert habe

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mrjj avatar image mrjj commented ·

So this DESS Green mode is like ESS gridpoint = 0 added with selling option from batery so it sets gridpoint to -xxxx based on several things like price and soc

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grua avatar image grua mrjj commented ·

And also using grid for loads and charging battery from grid If it makes sense

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rikvanwesterveld avatar image rikvanwesterveld commented ·

In general the Green mode works quite okay now, some strange decissions still.
Every morning I see the upload to the grid is just "avoiding" the highest pricepoint, see screenshot below from this morning.
Just before and after the highest pricepoint it starts to load the load to the grid?!

Is this a glitch in the algorithm?

ess-21-05.jpg

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dutchsolarfreak avatar image dutchsolarfreak rikvanwesterveld commented ·

Simular behaviour but not at the higest price

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isavednokat avatar image isavednokat commented ·

I've just tried Dynamic ESS for the second time on my two systems and have had to turn it off again within a couple of hours because it's wasting energy...I'm running with no buy back possible from the grid (but I can dump energy to the grid) and with some A/C coupled PV that doesn't talk to the system...I found both systems pushing power out to the grid whilst charging the batteries at only 1/3 of the rate those can accept - in fact pretty much all charging was happening directly from DC side solar charge controllers - my theory is that whilst ESS has a setting for how much power can be produced by such A/C coupled PV and tries to take account of it Dynamic ESS is simply ignoring the possibility that the A/C side may generate an excess above load and when it happens chucks it away instead of storing it in the batteries. My Dynamic ESS settings include Green mode and not allowing batteries to discharge to the grid. Edit: I have updated my Cerbo GXs to 3.31 and it's not helping although that was supposed to fix a bug in this area.

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Dirk-Jan Faber (Victron Energy) avatar image Dirk-Jan Faber (Victron Energy) ♦♦ isavednokat commented ·

It looks like your pricing is rather static, and when we were developing Dynamic ESS we didn't consider using it with non-changing prices.

For these cases there is not much added value compared to regular ESS.

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Nikolaus Tittler avatar image Nikolaus Tittler commented ·

Hi,

currently I've 2 issues:

1) Export to grid when battery needs still to be charged. (Export to grid from battery is off)

2) 48V Battery charing stops sometimes? when battery is full. When dess is turned off, feeding to the grid starts. When I turn dess on again, 48V keeps feeding to grid (as it should). (have no pics for that right now)


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grua avatar image grua commented ·

@Dirk-Jan Faber (Victron Energy) has this really been "grid to battery" today or is it just a bug in the visualization and for real it was "grid to load"?

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ID: b827eb273733

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You can check that under the grid breakdown graphs. It looks like it was indeed grid to battery yesterday. 0.18 kWh seems to have gone to your battery from the grid betwen 14:00 and 15:00.
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heiko avatar image heiko commented ·

Hallo,

Hab da auch mal eine Frage. Ist es in der Entwicklung von DESS auch mal geplant, das man selbst einen maximalen Ziel SOC festsetzen kann,bis zu diesem dann DESS aufladen darf?

Ich habe oft das Problem mit der Solarprognose. Mittags wenn der Strompreis günstig ist, dann wird der Akku auf 100 % geladen. Und es kommt manchmal am Nachmittag bis Abends genug Sonne oder auch Schattenstrom, welcher dann ins Netz geht. Ich bekomme keine Einspeisevergütung.

Ich würde dann nämlich den maximalen Ziel-SOC für DESS auf 80 % setzen und falls noch Sonne ab Nachmittag kommt, dann geht nicht ganz so viel ins Netz, so das der Akku noch aufgeladen werden kann.

Ich gratuliere Euch trotzdem schonmal zu der bisherigen Entwicklung .

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marceldb avatar image marceldb commented ·

The energie prices of 26 June in DESS are not the same as in EPEX. Does something goes wrong?

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prein avatar image prein marceldb commented ·

Yes, the entsoe data was wrong for a few hours due to some trading problems at epex.. Hopefully @Dirk-Jan Faber (Victron Energy) can do a reload of the data, since entsoe has fixed it now

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avalon64 avatar image avalon64 commented ·

I have been trying to activate ESS via the VRM portal in green mode for a few days now.
Unfortunately, after entering all the parameters, I get error 1520 when sending.

I have also noticed that it is not possible to make the entry on devices such as the iPhone if it is set to German, as in my case. There is no "." available, I can only enter decimal numbers with ",".

It would be nice if you could use ESS, I had waited for the beta phase and now have to realise that this is far from over.

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heiko avatar image heiko commented ·

Hallo, @ Dirk-Jan Faber

hab da eine Frage an die Entwickler von DESS. Bin sehr begeistert von dem Tool.

Frage 1: Wie genau sind die Solarprognosen bzw. wie oft wird denn das Satellitenbild oder auch Wolkenradar am Tag abgefragt? Ich hatte vor einigen Tagen weiter oben schon einmal gefragt, ob es nicht auch sinnvoll wäre dem DESS auch einen maximalen Zielsoc vorzugeben. Bis zu diesem darf DESS den Akku dann laden.

Ich muß an manchen Tagen DESS beim laden unterbrechen,weil ich auf dem Wolkenradar noch einiges an Solarertrag für den rest des tages kommen sehe.

Frage 2: Berücksichtigt DESS auch Solartracking? Ich habe 4 Solarmodule und kann mit diesen der Sonne folgen.

Bin sehr dankbar für eine Auskunft.

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hans-fix avatar image hans-fix commented ·

Hi,

Some days ago I updated the venus os from 3.12 to 3.34 , the system is in trade mode.

If energy prices are high on the grid, the battery is discharged. So far so good.

But the battery is immediately charged after the discharge period, instead of waiting for even lower prices.

Currenrly target SOC says 68%, SOC is 95% but battery is not discharged.

Why?

Which of my settings can be wrong?

Regards

Hans


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drewzh avatar image drewzh commented ·

I'm having some issues with using DESS. My use case is charging batteries at night during the night rate and then discharging in the day when energy is more expensive.

Let me start off by saying the only reason for even looking into this feature is the lack of 'scheduled discharge' functionality with the normal ESS. I can start charging at night to 90% (and 6 hours charging) on a schedule between 23:30 and 5:30 (octopus intelligent tariff in the UK), but once this limit is reached, the battery goes into discharge, feeding the house with energy when it's inefficient (as my night rate is still active). The only way around this logic is to set the target SOC to 100% and then the system continues to charge for the full (6) hours until finally switching back to discharge at the correct time... this would work if it wasn't for the fact I don't want to charge my batteries to 100% due to battery wear.

So anyway, fast forward to DESS where I've had high hopes this will fulfil my simple requirements...

I've configured my day and night static rates + configured everything else to what I believe is correct.

The problem is, I'm seeing the batteries charge at night but then switch between charging and discharging throughout the night, which is inefficient and leaves me with circa 60% battery power in the morning to use throughout the day.

I figured perhaps it was a calibration thing and it will just pick up... but it's not - it did the same thing last night. Luckily my 4yo son woke me up so I took the opportunity to check on the battery again and luckily was able to set 'Keep batteries charged' to ensure they were charged for the morning.

So... still assuming this is a calibration thing, I've checked the forecast for night/tomorrow... which seems to be healthy... but the odd thing is, I'm seeing a period during lunch where we're using the grid for seemingly no reason.

Can somebody please sanity-check my assumptions and check the screenshots out to tell me if I'm doing something wrong here?

Many thanks in advance.

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piter271 avatar image piter271 drewzh commented ·

HI drewzh, maybe my input is too late, but I just joined the community and also, I'm fresh user of my DESS. I setup my system as Green Mode and with Dynamic prices, nevertheless I can point few items , you may consider for a change. #1 Battery : do you have few battery units or just one ? I believe few, if so, pls try to modify Maximum dis/charge power setting to reflect total dis/charge power of all your units, not for just one. #2 Setting re battery usage (current: No). Pls try to set it to Restrict selling to grid. #3 Check if you have inactive charging schedule in GX

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hereandthere avatar image hereandthere commented ·
Hello, for some reason in Green mode the charging to 100% does not start.

A pink bar appears (grid to battery) but when that time is due the bar moves to the next hour without doing any charging.

Anybody having a clue why this is the behavior?


Thanks

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Enrico avatar image Enrico commented ·

Hi,


I've been running in Green Mode for a few weeks now and it mostly works great! One thing that bothers me a bit is that when DESS starts selling power from the battery in the morning it always goes on a bit too long until it's at, or very close (too close i.m.o.) to, the minimum SOC (40% for me). So shortly after selling the energy it has to buy back from the grid at almost the same price. (there simply isn't enough solarpower here at 8am to start charging already)


Best regards,

Enrico Klein


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