article

Dirk-Jan Faber (Victron Energy) posted Oct 13, '23

CLOSED - Dynamic ESS on Beta VRM - part 2 (use new topic please)

CLOSED - Dynamic ESS on Beta VRM - part 2

Update 2023-11-28: This article has been closed for further comments. The follow up article can be found here.

UPDATE 2023-11-03: Venus OS version 3.20~17 (latest candidate release) offers several Dynamic ESS related improvements:

Remove the separate DESS MinSoc setting. DynamicESS now uses the ESS MinSoc.

Stop showing "Low Soc" errorcode when DynamicEss reaches the target SOC.
Fix bug that limited solar chargers in relation to the target SOC. Rather than limiting, get there early, and power loads or feed excess into the grid.
Implement restrictions for the German market:
- Two modes are supported: Disallow export from battery to grid, and Disallow import from grid to battery.
- When converting from DC to grid is disallowed, export-power is limited to local consumption, plus DC-coupled PV (which is green).
- When converting from grid to DC is disallowed, import-power is limited to AC-coupled PV.

Controls for setting the restrictions can be found under the Dynamic ESS battery settings.

For Node-RED users, you can read how to configure it here.

First of all thanks for the overwhelming responses to the first beta release of Dynamic ESS on VRM. As the previous post on community became very large I’ve closed that one and started this new one, containing what we have done after the initial deploy on beta VRM and our plans and focus for the coming weeks.

We got quite a lot of questions/remarks on why the system is sometimes (dis)charging on the grid. Dynamic ESS does keep the planned battery usage stable while punishing the forecast inaccuracies on the grid (selling the excess to grid, buy the additional need from the grid). This can be less ideal, but it is an issue of the forecasts being inaccurate, nothing that the Dynamic ESS decided. We’ve done several long running simulations and in the long run this proved to be the most cost-effective way. But we are still looking on ways to improving this.

Here is an update of improvements made in the past weeks:

Removed the separate Dynamic ESS SOC from the settings, as it seemed to be an unclear feature to many beta users and does not work well.
Improved the calculation of the figures showing what you would’ve made without Dynamic ESS, so it is a fairer comparison
Improved the configurator, so editing data in one step doesn’t force you to undergo all steps
Improved the energy graphs on the dashboard
Improved the overview of the configuration settings, so you can see you configuration in one glance
Improved the configurator, to not show bidding zones when the country selected doesn’t have those
Pass the battery capacity entered in DESS to the GX device

To be completed before official release:

Allow you to see past and future data (plan for tomorrow) for Dynamic ESS on the dashboard
Inform in case there is a problem with generating Dynamic ESS schedules, and why this is happening (unable to fetch prices from entseo for example).
Improve the UI and wording around the amounts earned / costs with and without dynamic ESS
Add a setting to disable selling from battery to the grid for your installation; as required for Germany as well as other areas.
Improve validation on the input fields in the configuration
Add a link in the configurator to an excel that helps you calculate your battery costs
Add site specific currencies to Dynamic ESS

With above, we expect to have it ready for first official version.

Many plans are already being made for what is next, here is an overview.

Incorporate battery efficiency losses into the algorithm
Support differing transportation costs through different times of the day
Allow to specify a feed-in time range to allow for selling from the battery to the grid at set times
Show the state of Dynamic ESS and any potential error codes more prominent on the dashboard
Simulate what an installation would’ve earned in a week’s time with and without Dynamic ESS for new users
Allow copy-pasting formulas so configuration for multiple installations becomes easier

The manual will always cary the most up to date instruction and also contains a FAQ, so make sure to check that too, before posting a new question / remark.

For those of you who missed the original post, and wonder what this is all about. Dynamic ESS is an algorithm that aims to minimise the costs made on the grid and battery:

By scheduling charge/discharge cycles of the battery,
While taking grid limitations, battery specifications and day ahead energy prices into account,
When it can, it also considers the consumption and solar yield forecasts when scheduling.

This has been running for a while now on Node-RED where we got the first child diseases out. It is now time to increase the audience, so hence the roll-out on beta VRM.

You can get started with it on beta-VRM via Settings → Dynamic ESS.

There is a (work-in-progress) manual and this article will be updated too the coming days. All feedback can be provided below.

Note that Dynamic ESS applies mostly to countries in Europe that work with so-called “day ahead pricing”. For fixed priced contracts, the VRM version can also be used outside these countries.

For those of you who aren’t familiar with beta VRM, you can log in through this link with your normal credentials.

A webinar about this subject has been held on the 26th of September. The recording of the webinar can be found on our YouTube tech channel: https://youtu.be/YU9jXyfM-eI

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stephanoffice commented · Oct 29, 2023 at 06:50 AM

Dear Victron,

Im very happy with the new DESS. Running is for some days now i noticed that there keeps beeing injected excess solar power to the grid. I know that the current algorithm is a predictive analyses one and that the prediction part has limits and works in the long run and can be off now and then. That explains why that happends. But maybe you can add an option in the future that tries to keep all the solar in the battery (non predictive) like the ESS option does. This option could increase the businesscase for DESS depending on the Solar costs. This is also better for the lithium battery’s because the battery’s will get more to 100% and ballance more often. This reduces the risk of unbalanced battery’s because the “with battery protection” option is not a very good combination (financialy/pratical) with DESS.

Greetings

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heinvdb stephanoffice commented · Nov 07, 2023 at 08:05 PM

@Dirk-Jan Faber

In my opinion, the system needs 3 extra parameters.

1) An adjustable safety buffer on the low side of the battery. If there is less sun or more consumption, in a given hour than predicted, the system does not have to reach its target SOC. It could use its buffer to continue with its predicted algorithm and can correct this later when the prices are lower.

2) An adjustable buffer on the high side of the battery. If there is more sun than predicted or less consumption than predicted, the system can use this buffer to fill so that it can correct later on when sell prices are higher.

3) An adjustable time interval (every week, 2 weeks or once a month,...) at which the system charges the battery to 100% at low prices or a lot of sunshine. Then the SOC can be reset correctly and the battery cells can balance again.

Hopefully the Victron-team can modify the DESS system in this way to overcome some limitations and thus create a better DESS system.

Kind regards,

Hein

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koll heinvdb commented · Nov 20, 2023 at 11:24 AM

Hello!

How can i add flexible grid fees to electricity price? I have 0,07 eur grid fee for daytime and 0,04 eur grid fee at night.

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Jakub Fiala commented · Oct 18, 2023 at 09:39 AM

Hello.
It is clear to me that smart forecast-based planning is difficult, especially because of the unpredictability of production as well as consumption.
The result, for me, is almost always wrong. For me, it would be quite sufficient to control the ESS charging mode, ESS discharging mode and SoC settings. So - if the price is below X charge the ESS, if the EV is pinned start charging, if the price is above X use only the battery, if you reach SoC XX then switch to the grid. I'd like to get notifications about everything. Even advance notice - there will be a low price, if you can, plug in the EV. Buying surplus for me only from PV if the above is met.
That said, a scheduler based on SPOT prices is fine for me.

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Dirk-Jan Faber (Victron Energy) ♦♦ Jakub Fiala commented · Oct 18, 2023 at 02:37 PM

For now that can only be done using Node-RED implementation (which can be run while using the VRM beta version at the same time); just make sure not to overwrite the schedule.

This example should help in achieving your goal, where some scheduling is done based on the price being above or below the average day price: https://github.com/victronenergy/dynamic-ess/blob/faberd/extra-example/examples/nodered-ui-with-vrm-dess-with-average-price-switching.json

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Jakub Fiala Dirk-Jan Faber (Victron Energy) ♦♦ commented · Oct 18, 2023 at 03:09 PM

Hi Dirk,

I will check it, thank you for reply. Jakub

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g8n commented · Oct 19, 2023 at 08:29 AM

Thanks for the great work! I tried to find the setting for Germany that prohibits discharging the battery to the network, unfortunately it was not possible? I have the latest 3.11 version and also updated in Node-Red and use beta-VRM? Or does the disabling of the discharge of the battery happen automatically? Because then it does not work. Today the DESS wanted to load battery power into the grid again. Although only an extremely small solar forecast exists and also the solar remuneration is very minimal compared to the purchase price for electricity.

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tuxedo0801 g8n commented · Oct 25, 2023 at 02:08 PM

Same issue here: DESS charges the battery due to low SOC and high demand and low buy-price...but after demand drops, it discharges the battery into the grid... I bought for ~30cent and sold for ~7cent ... So evene if I where allowed (in germany) to sell from battery, this makes not that much sense.

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Dirk-Jan Faber (Victron Energy) ♦♦ g8n commented · Oct 19, 2023 at 12:43 PM

That option is not there yet. It is still under "To be completed before official release".

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Christoph Taschke Dirk-Jan Faber (Victron Energy) ♦♦ commented · Oct 25, 2023 at 07:22 AM

My system is also planning to discharge the battery in order to sell to the grid although I have set net feed-in to zero in the (ordinary) ESS settings. Fortunately, it doesn’t come to this feed-in in reality. So the forecast is always inaccurate.

Therefore, I wonder why the dynamic ESS forecast doesn’t take into account my (ordinary) ESS settings in the remote console.

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gdhondt commented · Oct 19, 2023 at 11:40 AM

Hi Dirk-Jan,

My DESS give a alarm. Dynamic ESS battery level unknown

In VRM the battery level is shown. So maybe it’s a fault in Dynamic ESS software.

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kudos50 gdhondt commented · Oct 19, 2023 at 12:09 PM

Same here. Whereas Cerbo says all is good. Glitch in the matrix. Seems to have resolved itself.

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Noel kudos50 commented · Oct 19, 2023 at 12:34 PM

Same here...

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kudos50 commented · Nov 07, 2023 at 08:43 AM

It may be just me interpreting things incorrectly but it seems DESS is handling AC PV the same as it does DC PV. Whereas AC PV for me has about 8% efficiency loss going in and out but DC PV only has 8% loss going out and negligible chemical losses going in.

I tried using battery costs to incorporate efficiency losses but these numbers will be different for AC PV and DC PV.

Can we try and distinguish between the two please ? At this very day with a low of 28cents and a high of 35cents just storing AC PV in the battery will cost 31 cents without battery cycle costs (and 33 cents including one-way battery cycle costs). Getting it out of the battery will cost another 3 cents making it 34 cents without having calculated battery cycle costs So kind of pointless. But storing DC PV is actually what the system was designed for and only costs 3 cents making it 31 cents.

For those that do calculate their battery cycle costs, storing energy in NL on days like this is rather pointless with a 10cent total cost :-)

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hominidae commented · Oct 14, 2023 at 06:15 PM

@Dirk-Jan Faber thanks again for that tremendously fine piece of work!

Please note: "Add a setting to disable selling from battery to the grid for your installation; as required for Germany as well as other areas." is only one half of the story. It depends on the type of metering installation ... in my case I am allowed to feed-in/back from batttery to the grid but not allowed to charge the battery from the grid.

hence such a switch in the setting should cater for both variants!

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Dirk-Jan Faber (Victron Energy) ♦♦ hominidae commented · Oct 16, 2023 at 01:07 PM

Thanks for the remark. Though making it all little more complex to implement, we'll make sure to add that option too.

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Dirk-Jan Faber (Victron Energy) ♦♦ Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 07, 2023 at 03:24 PM

@Hominidae : Now that the restrictions can be configured (mainly for the German market), can you test if it works as you expect and provide some feedback?

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Robert Zeugswetter commented · Oct 14, 2023 at 10:48 PM

@Dirk-Jan Faber thanks for your effort.
"Removed the separate Dynamic ESS SOC" - Can this feature still somehow be used with the Node-RED implementation?

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tdupas Robert Zeugswetter commented · Oct 15, 2023 at 07:01 AM

and perhaps a follow-up question. I see that in the latest venus os (3.11) the setting is still there and can be altered, but seems to get reset back the next push. Would have liked to still use that feature, to have some deliberate "buffer" between the minimum SOC only to be used at power outage and the "minimum SOC as seen by ESS and used for calculations".
So correct that it's "really gone", or could make a reappearance for users who want it?

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Dirk-Jan Faber (Victron Energy) ♦♦ tdupas commented · Oct 16, 2023 at 12:55 PM

It could return in the future. But we don't want to have an unclear setting that does not function properly.
While you can still read from and write to it from Node-RED, it will be ignored by the dbus-systemcalc proces.
If you want an extra buffer, you can increase the normal minimum SOC. In case of power outage, that is still available.

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kudos50 commented · Oct 16, 2023 at 09:19 AM

Considering the enormous amount of kWhs going into an EV even in relation to my rather power-hungry house, I for one decided to not charge batteries from batteries unless I really have to.

Not so much because it's a bad idea, but because it's human planning/logic that is too hard to automate. Too many variables. As there is no right or wrong here, would it be possible (or already the case?) for the forecast calculations to not incorporate consumption data generated whilst DESS was in "Off" state. That way some of us may be able to "skip" the excessive consumption windows by switching from auto to off and back for EV charging.

And for home automation enthusiastics out there, can we make the switch available using modbus please so I can trigger auto/off and back if a charger is in use ?

I realise this will not cover all use-cases. But I do hope for some it improves the daily use of the new DESS product and it may provide Victron with better statistics pending the silver bullet for EV charging forecast.

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Dirk-Jan Faber (Victron Energy) ♦♦ kudos50 commented · Oct 16, 2023 at 01:14 PM

As soon as all the dbus paths are solid, we'll add them to dbus_modbustcp. Meanwhile, you can use the Node-RED custom output node to write to the dbus service `com.victronenergy.system` and path(s) under `/DynamicESS`.

Incorporating EV charging plans are being made, but that will get the attention it deserves after the official release of dynamic ESS on VRM.

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kudos50 Dirk-Jan Faber (Victron Energy) ♦♦ commented · Oct 16, 2023 at 02:31 PM

Yeah I can imagine that being a huge challenge. In the mean time, does a manual switch to off and back to auto indeed prevent the statistics from that period from being included in the forecast ? Probably not, but a guy can hope.....

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daniel-feist commented · Oct 17, 2023 at 02:06 PM

> This can be less ideal, but it is an issue of the forecasts being inaccurate, nothing that the Dynamic ESS decided

I agree, but for Dynamic ESS to be truly dynamic it needs to also deal with the situation where the forecast is not accurate. The current algorithm is great, but there needs to be a second algorithm that is used within the 1hr slots that deal with.

- Lower than forecast average/instantaneous PV production (due to clouds for example)
- Higher than forecast average/instantaneous consumption (due to cleaning/cooking etc.)

It's a shame that there is nothing in your post-release roadmap currently to address this, as a lot of people (like myself) will avoid using Dynamic ESS when they see it i) importing at expensive times when the battery is nowhere near empty, ii) exporting at very cheap times when the battery is nowhere near full, just because it's following target SoC blindly without accounting for actual PV/consumption.

> Allow to specify a feed-in time range to allow for selling from the battery to the grid at set times

Will you also add a time range to allow import? Providing time ranges to allow import and export could be a way of manually addressing the concerns above, especially for people on fixed rates with a cheap rate overnight who don't want to ever import during the day, even if PV/consumption doesn't match the forecast. Ideally separate configuration of this shouldn't be needed if the tariff has already been defined though.

I still think there must be some way to combine Dynamic ESS for the day planning with ESS (with specific min/max setpoint and SoC parameters) for the instantaneous management of import/export. Has the team given this any thought?

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kudos50 commented · Oct 17, 2023 at 02:58 PM

Does anyone else have issues with the new charts ? For me they work some of the time but since this morning I have no SOC forecast in the system overview section, no numbers in the costs and earnings (it does show the graph) and no energy overview.

Happened yesterday as well but seems to have resolved itself until this morning.

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john245 kudos50 commented · Oct 17, 2023 at 04:38 PM

@kudos50 I have this issue for weeks.

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kudos50 kudos50 commented · Oct 24, 2023 at 09:19 PM

Not sure anyone is still experiencing this but for me nothing has changed since the last post. First I thought it might just be me making changes to the config here and there. Or too much EV charging that hopelessly breaks forecasts.

But it's not. Today, again the whole day no soc forecast in the graph and no energy graph. And when the energy graph is available it happens pretty often that there is a gap as mentioned earlier. A gap that usually resolves itself before the hour has passed bringing consumption numbers back inline with energy.

On a truly positive note: I think it's just the graphs. The decisions DESS has made have been irrational only once or twice. I did put in higher numbers for battery costs to compensate for the inherent energy losses in a 48v system as well as the actual costs of the battery system. As mentioned in "what's next" it would be better to incorporate that separately as cost of losses is relative to price whereas battery costs is not.

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miklosbakos commented · Oct 18, 2023 at 07:27 AM

Hi Team, Editor,

Can you please replace the Energy Graph with the correct one? If I look at every chart: price, battery, grid, etc. the energy one doesn’t make any sense, it shows a different day and/or different site. It’s wrong in the manual and in the Node-RED page as well. Please add charts that belong together.

Thank you

Miklos

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Dirk-Jan Faber (Victron Energy) ♦♦ miklosbakos commented · Oct 18, 2023 at 01:17 PM

Hello Miklos,

Thanks for the feedback. I am happy to update manual, but need to know if and where it is wrong. It will help if you provide screenshots where you point out an time span where the graphs and calculations don't match.

If, for example, I take the following energy graph between 11:00 and 11:59

So in that time span:
- Solar to battery 0.64 kWh
- Solar to Grid: 3.80 kWh
- Total Solar: 5.09 kWh
- Total Consumption: 0.66 kWh

Then I'll add the energy graph for that same time span:
- Grid usage: 3.80 kWh
- Battery usage: 0.64 kWh

The grid seems to be used when feeding back from solar (3.80 kWh). The rest of the solar went to the battery (0.64 kWh) or got consumed (0.66 kWh). If I add those three numbers I get to 5.10 kWh (which is only 0.01 kWh off the Total Solar number, which is probably due to rounding of the numbers).

So you see that the numbers correctly match up. If your graphs are wrong, please also report your vrm id, so we can check.

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kudos50 Dirk-Jan Faber (Victron Energy) ♦♦ commented · Oct 19, 2023 at 07:46 AM

Think I have a gap in the graphs as well. Please took a look the example below in the knowledge that inverter is set to 5100 and charger to 4500. Seems to indicate it's getting >5100 from battery which is not possible. I also have examples of almost 6kW from battery.

In this example the consumption matches the system overview so I would expect 0.68 of consumption to come from battery instead of 0.38 and for the 5.10kW to be 0.68kW less ?

I'm @290452

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kudos50 commented · Oct 19, 2023 at 08:01 AM

Some of us are 100% electric for heating and DHW. Like an EV, outside temperature and solar forecasts will significantly influence DESS consumption forecast.

As every house(hold) is different, making this fully customisable would defeat the purpose of a consumer grade / fully automated portal. But.... if we simply trust the Installers to have done their calculation well, we already have the number we are looking for: the capacity of the heat pump.

Can I suggest to allow the configuration to request the capacity of a heat pump if any so outside temperature and solar forecast can be included in the algorithm ? In my case the last days have been cold by average but we had loads of sunshine. So the heat pump worked hard a night and was not needed during the day and evening.

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gdhondt commented · Oct 19, 2023 at 01:02 PM

Couldn’t find the answer on my question below:

When running in DESS. Will the system switch to ESS during grid outage? (Disconnect AC in)

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gdhondt commented · Oct 19, 2023 at 04:35 PM

In DESS mode the system give overload warning on L1 L2 and L3. Is it a glitch in DESS software? or can I prevent it by throttle down the “maximum discharge power” in DESS settings?

Currently running 12kw maximum discharge power with 3phase multi 48/5000 environment temp is 23.5 degrees Celsius

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grua commented · Oct 19, 2023 at 07:19 PM

I have defined no different prices on weekdays and weekends:

But the summary shows the opposite:

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grua commented · Oct 20, 2023 at 06:04 AM

I just activated DESS last night. Shouldn't the target SOC also be shown in the forecast in today's system overview? However, target SOC is actually missing:

At What is Dynamic ESS? | Dynamic ESS Overview the example image looks like this:

Why isn't it shown on my installation?

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grua grua commented · Oct 20, 2023 at 06:24 AM

Oh, I was too impatient. Has just now been displayed:

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grua grua commented · Oct 20, 2023 at 08:23 AM

crazy, target SOC disappeared again. And if the target SOC is not displayed, also earnings will no longer be displayed:

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maxx8888 commented · Oct 20, 2023 at 06:39 AM

Great work! Just enabled DESS also on my Installation for testing.

I think somewhere on the Webinar I've heared that BatteryLife should be disabled when using DESS. I was wondering how i can keep my battery in a good charging state then?

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kudos50 maxx8888 commented · Oct 24, 2023 at 09:50 PM

Webinar also mentioned DESS business case is hard to build using none-lithium cells. And for lithium cells I guess turning off battery life is less of an issue? Specially managed batteries seem to overcome the SOC calculation and cell imbalance challenges due to the small voltage range of life pretty well without frequently reaching 100%.

Since Tesla started using similar technology they recommend charging to 100% regularly without mentioning why. I guess the added degradation of having a full pack out in the freezing cold is not as bad as having people call roadside assistance their battery died on them at 15% due to incorrect SOC calculations over time.

No matter the platform. It is questionable to leave a LiFe pack at 100% for extended periods of time or at 5% for that matter as 95% DOD is regularly advertised. Maybe just override DESS and simply click "buy". I know I will :-)

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larsea-dk kudos50 commented · Oct 28, 2023 at 07:54 PM

The 100% might be due to a „reset“ of the SOC to 100% calibrated to a full battery voltagewise also.

My Smartshunt SOC do drift over very short time (weeks) if not fully charged, so might make sense to do a full charge now and then. I haven’t found or heard of other ways to calibrate the SOC….actually though it was not necessary.

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CM commented · Oct 20, 2023 at 08:10 PM

Hi Dirk, will this dynamic ESS allow us to also ignore ac input for those of us who don’t live where export to grid is allowed , so we can also enjoy ESS features without export?

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Dirk-Jan Faber (Victron Energy) ♦♦ CM commented · Nov 15, 2023 at 04:23 PM

Since candidate release 3.20~17 we've added the ability to set restrictions:
0 = No restrictions
1 = No exporting from battery to grid
2 = No importing from grid to battery

You will need to run the latest candidate feed for this to work and be selectable from VRM.

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stephanoffice commented · Oct 24, 2023 at 04:04 PM

Thanks for the great work! Really looking forward to this. Everything works fine for 2 days now accept the dynamic ess dashboards. The cost view stays blank, the energy view stays blank and the planning view only shows the history and not the forecast. How do i get te dashboards working?

Greatings

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vanwalsum stephanoffice commented · Oct 28, 2023 at 08:06 PM

Same here. No cost/earnings estimates.

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stephanoffice stephanoffice commented · Oct 31, 2023 at 06:05 PM

Solved, forecast is working

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kudos50 commented · Oct 27, 2023 at 10:34 PM

Think I said somewhere this week calculations were pretty good. Right after posting that the decision making process was less successful.

Seems that the battery costs now match the documentation. Instead of the costs being calculated twice for ingress and egress they are now calculated as a cycle as mentioned in all the documentation. Description of the setting has been changed accordingly. Would have been nice to get a small heads-up as that influences the decision making.

After correcting the battery cost setting I still have moments in which energy is bought from grid only hours before it will be a lot cheaper and vice versa. It's mostly smaller amounts so I am happy leave it alone for now. Last but not least, the graphs are still odd. After midnight nothing shows and scale changes from 1h to 30mins. And as mentioned elsewhere in this thread, calculations and energy often simply do not show.

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kudos50 commented · Oct 29, 2023 at 08:02 AM

Switched to buy last night and this morning with batteries at 100% DC PV was holding back / not producing. Switched back to auto and all is good. Feed to grid for DC is enabled. Is this works as designed?

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Paul Beskeen commented · Oct 31, 2023 at 03:25 PM

As has been mentioned by other commenters, Octopus Energy in the UK is the key supplier for many, if not most, of the energy savvy users in the UK. They are quite innovative in their tariff offerings. In particular, the Intelligent Octopus Go tariff has seen a growing uptake of late. This provides a fixed 6 hour window of cheap rate electricity, coupled with dynamic slots outside this window where your EV will also be charged. These slots are determined by Octopus at the point you plug the charger into your EV. Octopus then commands your charger (Ohme/Zappi only at the moment), or your EV (several manufacturers supported) to charge during these periods. The key consideration is that your entire energy supply becomes cheap rate during these periods. This approach however has implications for your battery - if you do not manually intervene to put your battery into charge mode, then your battery will drain to supply the EV rather than using the mains!

DESS looks like it could (eventually) provide a basis for automation of this functionality, which would be a very welcome development for UK Victron users. I understand that this may not be a priority for Victron initially, but I want to at least get it on the radar along with some basic background info.

Support for half hour scheduling slots is a key prerequisite for *any* UK tariff support - even for fixed schedules, so hopefully that will be implemented sooner rather than later.

Home Assistant already has multiple plug-in support for determining these dynamically allocated EV charging slots, so perhaps there is a halfway house solution? Is there a way (DESS or otherwise) for Home Assistant to either put the Inverter in and out of "Keep Batteries Charged" mode, or to add charge slots into the ESS schedule, via Modbus or MQTT?

https://octopus.energy/blog/agile-smart-home-diy/

https://developer.octopus.energy/docs/api/

https://www.guylipman.com/octopus/api_guide.html

https://github.com/BottlecapDave/HomeAssistant-OctopusEnergy/blob/develop/_docs/entities/intelligent.md

There are also (for some UK regions) Octopus "Power-Ups" which are slots with completely free electricity, when green generation is exceeds demand locally - that also would be good to recognize and automatically schedule battery charging for.

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bouz commented · Nov 01, 2023 at 12:24 PM

my PV system is AC connected. compared to the PV system, the battery is small.

PV: 47,5kWpeak, Batterie 4,8k Wh (no connection from victron to the PV inverter)

Observation after setting up the dynamic EES:

- No value display in the trend energy (Loading...)

- Consumption from the storage <50% a day (Before mostly 1 cycle a day).

- Display expected PV generation is missing (prediction for power / m² is present in the extended trend) [Should be calculated in this setup via a parameter (is there any existing parameter?) or via a model derived from the electricity export].

- Target SOC often too low in high price periods.

Settings:

- No grid feed

- Optimized without battery life

- Dynamic ESS Auto

Is there another setting I need to check? With the option I had the hope to increase my battery usage in the expensive periods. Currently, despite Dynnamic EES here, I still have high power draw and battery usage has dropped to half a battery cycle. On bad weather days I also lack the discharge during the day when dei PV generation is not sufficient and with the expected PV yield the battery can probably be charged again.

energy.png price.png trend.png Trend_october.png EES.png

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kudos50 commented · Nov 02, 2023 at 04:03 PM

@Dirk-Jan Faber can you please help me understand the import / export power settings ? Documentation says to set import export to grid max or system max which ever is lower. It also says this is only used for calculations not for imposing system limits.

In my use-case this means the charging forecast during cheap rates is limited by the consumption forecast. In other words, it's subtracting consumption from grid limit so it can charge what little remains.

I have a 3 fase MultiPlusII setup and the system efficiency is better if not running at full power. I have therefore configured grid in to 3.75kW (75A) and export to 4,5kW (90A). Combined with heatpumps and/or EV charge forecast this results in DESS not charging at cheap rates as consumption is higher than grid import export settings. Whereas like you, we have 3x25A = 17kW grid connection.

I can follow documentation and set grid to system capability (import 5.250 export 7.200 or something like that) but even 5,2kW import with a big heat pump, or worse, BEVs will still prevent the system from charging. Unless of course, I simply enter 17kW but that would break import export calculations.

So basically my question is; How can I ensure DESS calculations to charge are still OK whilst not being limited by the grid import setting. Can I separate settings for calculations and actual grid connection to prevent consumption forecast from outweighing charge.

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blacksun kudos50 commented · Nov 03, 2023 at 05:14 PM

Hello, great job.

Some time ago I entered the price/kWh in cents in some field and then ran DESS for a while. Now of course I have incorrect values in the graphic. Can you delete all values somewhere and start again from the beginning?

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ojack commented · Nov 04, 2023 at 05:21 PM

Hello Dirk-Jan,

thanks for implementing the restrictions for Germany. I activated "Disable discharging to grid" and started a new try with DESS. The new settings do what they should do but I have another thing to complain.

This is todays result: (min SoC is set to 30%)

I was surprised that the system started to feed in after reaching merely 60% SoC. There would have been enough solar today to easily reach 100% SoC.

The price structure here is a rather high dynamic buy price p+0.22 and a low constant sell price 0.07. So for my understanding it should be never a good idea to feed in exept the battery is at 100%. It should be the target for DESS to avoid buying from grid as much as possible. If buying from grid is not avoidable because of bad weather or a too small battery the DESS should try to buy in the low price hours.

Can DESS achieve this with appropriate settings? What should they be like?

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vestax-1 ojack commented · Nov 05, 2023 at 07:01 PM

Definitely, I see the same behavior (PV production have been moved to grid) even if the Battery SOC wasn’t at 100%. Some hours later the system charging battery from grid. Make no sense in my eyes.

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ojack vestax-1 commented · Nov 05, 2023 at 07:30 PM

I think that's the fundamental problem with the strict hourly target Soc control. As soon as consumption or weather deviates from the forecast, it doesn't work well. And deviations are normal. Who bakes cakes at the same time every week? And everyone knows how accurate weather forecasts are, especially when you want to have it hourly.

I think it would be better to evaluate the predictions over longer periods of time. You would have to e.g. evaluate whether the solar forecast for the coming day can cover the consumption forecast. If that doesn't work, energy must be drawn from the grid during a period of low prices until the SoC is sufficient to get through to the next low price phase.

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ojack ojack commented · Nov 08, 2023 at 08:16 AM

Yesterday I tested DESS again with different settings. I answered “can you sell energy on the grid” in the negative. Result was better and Solar charged the battery to 100% SoC. Unfortunately, with this setting there is no longer any excess DC supply from 100% SoC. In addition, there was a completely unnecessary battery charge from the mains at a very high purchase price at 9 a.m.
Unfortunately, DESS is still unusable for me and I deactivated it at 1 p.m. (Therefore, surplus feed-in is also shown in the graphic from 1 p.m.)

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ojack ojack commented · Nov 10, 2023 at 09:17 AM

Another Test with extreme high buy price (p+1) and extreme low sell price 0.001 to force DESS to use solar for myself.

Result ist not better at all. The system did some significant feed in yesterday and took energy from grid to charge battery at high buy price.

Today it wants to feed in all solar from SoC 65%. This would lead to reaching minSoc 30% at 23:00 and using expensive grid for the rest of the night.

Normal ESS will have no problems to fill up my batterie to 100% today because of a sunny day and then the battery can cover the whole night until solar starts charging again tomorrow.

So I deactivated DESS and hope for changes.

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paulcupine commented · Nov 07, 2023 at 06:40 AM

The display of the config value for "Different prices for weekdays and weekends?" is inverted (says "yes" when "no" and "no" when "yes") on the settings display page vs the actual configuration. If you click to edit, it then shows the correct value.

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paulcupine paulcupine commented · Nov 07, 2023 at 06:41 AM

Config display.

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paulcupine paulcupine commented · Nov 07, 2023 at 06:41 AM

Config edit

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Holger Schultheiß commented · Nov 07, 2023 at 12:00 PM

Hello.

I have tested the functionality under different situation and there is something strange to me (Venus 3.12 / Dynamic buy prices): It feeds energy into the grid once there is solar power available. My VRM ID is: b827eb9face6

Did I miss to configure parameters correctly? I would assume that the solar energy is to be stored into my battery. Especially because the forecast says that I will run in batteries later on today:

Minimal SoC is 35%.

Thx, Holger

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gnagflow commented · Nov 08, 2023 at 08:02 PM

Hello, is it possible to implement a dynamic Tarif for Austria —> EPEX AT, awattar, smartcontrol, spotty (all the same)

How long could it take to get dynamic hourly prices implemented?

thank you.

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maxx8888 gnagflow commented · Nov 13, 2023 at 04:49 PM

No need for Austria Tarife i think. You can use your own formula already. If you want to follow Awattar its simply „p“

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thekwchallenge commented · Nov 13, 2023 at 01:16 PM

Is anyone else having a problem logging into, and using betavrm. on Android devices now? I've tried different phones and tablets and both Chrome and androids native browsers. Normal vrm. works fine on all my Android devices, it's just the beta vrm.

/login reports invalid credentials even though they're not and the bookmarked dashboard page loads only the header and transport buttons but no ccontent. The problem started about a week or two ago, possibly at the same time I upgraded my Cerbo GX to the latest version.

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thekwchallenge thekwchallenge commented · Nov 14, 2023 at 09:29 AM

Update on this. The login issue is now resolved, probably a persistent session issue on my device however after further testing...

Google Chrome on Android does not display the dashboard on betavrm after login, but works correctly on the normal vrm website. Users can login fine and then select their installation but the following main dashboard page never loads correctly. This issue is present on Google Chrome and Samsung Browser but works correct on Firefox for Android!

All browsers work correctly on the normal VRM webpages but the BETAVRM pages are not loading!

Here is a table of results

Browser	VRM	BETAVRM
Google Chrome	Working	Not Working
Firefox	Working	Working
Samsung Browser	Working	Not Working

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samuel-brucksch commented · Nov 14, 2023 at 07:49 AM

Hi,

as I'm currently experimenting with different approaches, to charge with cheap grid prices and top up with solar, I know how difficult this whole topic is and also that it is not easy to make it right for everyone.

As it doesn't make much sense, to implement this myself, if it is already in progress of being added here, I'll try to help out as much as possible instead, so I can just use the provided functionality here and save time.

I tested this a bit and as it is highly dependent on the predicted forecast (both consumption and PV), so far this does not really work out well for me.

I charge my EV during times, when the price is very cheap. That randomly happens and is not really predictable. So the problem with that is, that the consumption prediction is totally off as can be seen in this screenshot:

The day consumption for today is way too high, i don't consume that much during the day normally. Also the nightly consumption has an average of 2kWh per hour with peaks up to 6kW. As can be seen in the first few consumption bars, my nightly consumption normally is around 300-400W.

As I still want to charge my car, I need a way, to tell the Victron system, that it should ignore a certain amount of energy, which I can provide to the system easily via node-red or any other means.

The thing is I have two EVs and I don't want to charge them from the battery anyways, so they should be completely ignoerd by the system. Would be nice though, to still see them in the dashboard, but they should be ignored for dynamic ESS.

So I see these options as a feasible solution to the problem:
- provide an API or something within Venus OS, to let the system know, the car is charging and with how much energy
- provide an API or something within Venus OS, to upload time scheduls, where the car charged, so the forecast can be re-trained

Either way this has to be implemented, as these kind of consumptions are just not predictable, especially if people have the possibility to wait for cheap prices, which normally happens once a weak or so.

@Dirk-Jan Faber is there maybe a way, to already let Dynamic ESS ignore the EV power consumption via node-red somewhow? It's also possible for me, to write a script, which emulates my charger as a Victron charger internally, if that helps.

Keep up the good work and let me know, if I can help out somehow, to test with EVs.

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kudos50 samuel-brucksch commented · Nov 14, 2023 at 08:18 AM

Your screenshot shows the same issue I'm having (other than EV and heatpump consumption): The soc forecast is gone from the chart. I can still see the next 4 hours on the Cerbo or in NodeRed and it still shows in the energy forecast.... but not in the forecast under "Installation Data" as is has the last month.

Is this change by design ? I'm on the latest beta, think the problem started somewhere around my upgrade from 3.12 to 3.20b18 but not sure it's related.

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samuel-brucksch kudos50 commented · Nov 14, 2023 at 05:54 PM

I can still see it very clearly on the node-red UI:

So it's probably only a displaying issue...

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Peter samuel-brucksch commented · Nov 14, 2023 at 08:41 AM

In Gbbvictronweb.gbbsoft.pl you can exclude charging of EV from load profile. :-)

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samuel-brucksch Peter commented · Nov 14, 2023 at 09:31 AM

Thanks Peter, looks interesting, but I want the Victron system to do all that stuff, they have to fix it anyways, so there should be no need for a third party service. Will still check it out though, maybe it helps as an intermediate solution.

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paulcupine commented · Nov 14, 2023 at 11:37 AM

Dynamic ESS does not take into account the generation of AC-coupled PV for the export limits. I have a 6kW (3ph) Fronius and have limitted the Dynamic ESS feed in to 12kW. There is also 6kW of DC coupled PC. If I set Dynamic ESS to "Sell" it dumps 16kW into the grid - 12kW from Multis (batt plus DC coupled PV), 6kW from the Fronius, less 2kW going to loads.

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samuel-brucksch commented · Nov 15, 2023 at 08:56 AM

To me it looks like the recalculation (that in node-red happened every 20mins) doies not seem to have any effect, when there is actually a change. For example tonight there was a foreast of a 3kWh consumption, so the system added a schedule to not discharge after that for 3h. However that forecast was wrong, so the battery had much more left, than forecasted, so my assumption would have been, that the schdules update and the battery actually discharges. But it still paused for 3h, after the forecasted consumption, although the battery level was really high:

The initial forecast showed a drop of 20% or so, but as you can see the actual consumption was way less, so there was no big drop.

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samuel-brucksch samuel-brucksch commented · Nov 15, 2023 at 09:01 AM

Also if i compare actual soc to what the schedule in node-red shows, it is very obvious, that the forecast is not properly adjusted

soc is 50%, but the forecast shows 60%

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kudos50 commented · Nov 15, 2023 at 08:44 PM

I'm experiencing about 80-100W continues battery discharge when the system is forecasted to be idle. Target SOC is the same for the foreseeable future and no DC PV at that time.

This behaviour causes the battery soc to drop around 2% in a full night which is OK I guess as energy is inverted to consumption. But knowing the 3 multi's are not very efficient if jointly managing 100W "battery drain" I was kind of wondering why this is happening. Why not save energy so it can be inverted when rates are higher.

If I set min soc to the current value the system comes to a full stop. Battery 0W idle and the Multi's stating that they are using about 11W. The same as you'd see if you let DESS discharge the battery on days where buy and sell are not within a profitable range.

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kudos50 kudos50 commented · Nov 16, 2023 at 08:31 AM

Downgraded back to 3.12 makes no difference. Turning off DC grid feed-in also makes no difference. It keeps inverting DC PV instead of charging it to battery. Maybe related to loads on ac-in being higher than DC PV but it's already feeding back AC PC back to grid as that is more than enough to cover loads.

Maybe I'm lucky and the sun stays around long enough to see what happens if DC PV alone can power AC loads. But by then AC PV will push 3kW back to grid on its own.

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john245 kudos50 commented · Nov 16, 2023 at 01:39 PM

Experiencing the same issue.

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kudos50 commented · Nov 16, 2023 at 05:22 PM

If you sell and end up with a soc that is lower than originally forecasted, DESS will immediately start charging to forecasted soc for that hour if changing back from sell to auto. In this example the sell ended with 41% a few mins past the hour whereas the forecast said 42%.

Suggestion to recalculate the next 4 hours for this use-case?

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Noel commented · Nov 17, 2023 at 12:27 PM

I'm lost.

I've setup the system like so (see image), but for some reason it is still giving back to the grid.
Should it not put this back into my battery's 1st until the battery's are full?

My setup is as follows.

3 phase going into the house (3x25A) <> Energy Meter ET340 L1, L2, L3.

My Victron setup consists besides of a Cerbo GX, one (1) MultiPlus-II 48/5000/70-48, an array of 28 PV's connected to a SolarEdge, and two (2) 10kWh battery's.

The "weakest link" in the setup is the MultiPlus-II as it can only charge / discharge the battery's with a max of 65 amps (3.5kW) . (note that the the battery's itself can handle 200 amps)

What I do not understand is why the setup decides to give back to the grid, and not put it into the battery!
I would have thought that this 545 watt's would 1st go into the battery's reason being that the 3.5 kW charging is not reached, AND that I have told it NOT to "sell back to the grid"!

Did I make a misstake in my setup configuration, or is this a normal thing?

Any help appreciated!

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ojack Noel commented · Nov 17, 2023 at 12:41 PM

Unfortunately, this is currently the case by design. The charge/discharge current is adjusted so that the calculated target SoC is reached on the next full hour. This is going to be tough. If surprisingly more solar comes in than predicted, it goes into the grid and if consumption is surprisingly higher than forecast, it is taken off the grid. In my opinion it's a bit of nonsense that will hopefully be changed soon. So DESS is useless for me too.

The only thing you can try is to activate the option “forbid feeding batteries into the grid” under battery. However, you have activated in network options that you cannot sell anything. However, this prevents excess feed-in at 100% SoC.

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ojack commented · Nov 17, 2023 at 12:53 PM

Hallo @Dirk-Jan Faber ,

Is that just my impression or will it no longer be possible to follow these long threads in a meaningful way at some point? It feels like new posts appear everywhere in the thread but you have to find them by chance. Or do I not know the right trick?

Apart from that you are doing a really cool job with VRM and also DESS. Even though I am a strong critic of the Target SoC method, I think in the end you will offer something that will help (almost) everyone. Keep it up and thank you very much!

Best regards

Olaf

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Dirk-Jan Faber (Victron Energy) ♦♦ ojack commented · Nov 17, 2023 at 01:26 PM

I too seemed to have that same issue. After consulting with Guy Stewart, it turned out that I had not checked some of the notifications settings. And I also had forgotten to press the "Follow" button on the top right (or it somehow got forgotten in the system).

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ojack Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 18, 2023 at 07:06 PM

Thanks for pointing out the notification settings. I changed something again and now I at least get a lot of emails when someone writes something. The many options there are somehow too complicated. And the daily digest option doesn't seem to work at all. @Guy Stewart (Victron Community Manager) I thought daily digest was supposed to be a daily summary of the topics followed or am I wrong? If I choose that I don't get any emails at all. Is there an overview of all the topics followed somewhere?

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ennotk commented · Nov 17, 2023 at 08:34 PM

I noticed two things when entering the details for a fixed contract with different buy and sell prices for weekdays en weekend. I entered 'yes' for the buy prices, but the summary shows 'no' while the schedules still show the different prices. For the sell price it is the other way around.

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Dirk-Jan Faber (Victron Energy) ♦♦ ennotk commented · Nov 17, 2023 at 09:10 PM

Thanks for reporting. Can confirm that it is not working as should. It will get fixed after the weekend.

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samuel-brucksch commented · Nov 18, 2023 at 06:39 AM

The consumption prediction really is ridiculous:

I charged my car again tonight, and suddenly it estimates a consumption of 10kWh for each hour of the rest of the day.

I managed to add my EV charger to VRM:

As you can see the consumption is known from the charger around the night time.

@Dirk-Jan Faber wouldn't it be an easy first workaround for the users with EVs, that you can enable ignoring EV consumption? That would probably really help those people. It's really useless for me right now...

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Dirk-Jan Faber (Victron Energy) ♦♦ samuel-brucksch commented · Nov 18, 2023 at 06:07 PM

Thanks for the report. There is indeed room for improvement. I'll talk to the other developers about it and see what we can do.

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samuel-brucksch Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 20, 2023 at 06:01 PM

Now i do not have so high consumption anymore, so looks like something was done. I have very low values during the night though
Which goes to as low as 0.09kWh, but my standby consumption is 350-400W...

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Noel samuel-brucksch commented · Nov 18, 2023 at 08:58 PM

I have the same problem, and I guess that an easy option would be to connect the EV charger on the "hot" side of the (in my case) ET340.

This so the ET340 (ie: the system) does not see the used consumption for the EV, and does not use it for doing it's calculations.

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ojack Noel commented · Nov 19, 2023 at 08:44 AM

But that can only be an emergency solution. This means that the system has no way of specifically charging the EV with excess PV.

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marceldb commented · Nov 19, 2023 at 12:14 PM

In DESS, you have to enter the Maximum Charge Power. That is usually the max charge power of the Multuplus configuration. That works well with AC solar inverters and grid connection. But what if I have a SmartSolar, which does not need the charge power of the Multiplus? It is additional charge power, but it is only available when the sun shines. And I want to use this SmartSolar power to charge more energy in less time, when the prices are low. How does DESS deal with this? Will DESS limit the grid power when SmartSolar kicks in, or is it indeed additional to the charge power as entered in the settings?

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Dirk-Jan Faber (Victron Energy) ♦♦ marceldb commented · Nov 20, 2023 at 08:21 AM

The filled out values for the powers in the Dynamic ESS settings are the capabilities. These numbers are being used by the algorithm to limit the maximum values what the system sets up its hourly planning. It is not actually setting limits for the system to use, as that will always stick to the limits that have been set on the system itself. Also see the manual here.

In other words, it is safe to have the capabilities in DESS higher than the limits on the system, though for the best calculation it is wise to not have them too much apart. Hope that answers your question.

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david-hruska commented · Nov 19, 2023 at 07:54 PM

I haven't been able to find anyone addressing this in the comments. I've been testing the DESS since the beginning of the month and I've noticed peculiar behavior when there's no planned battery discharge for consumption. The sensor on the multiplus appears to be 'idle,' but the smartshunt keeps showing consumption. In my case, it's around 1% over 5 hours (360w). It's not much, but it seems unnecessary to me. When the battery percentage reaches the set minimum, it stays 'idle' reliably and doesn't discharge at all.

The second issue pertains to charge scheduling. I've set 'max import' to 15kW, 'max charging' to 10kW, but in the plan, I see it wants to charge, for example, 25kWh within a single hour. When it fails to do so, it continues charging in the following hours. That wouldn't be an issue if the first hour didn't start just as the price per kWh begins to rise slowly, resulting in unnecessary charging at a higher cost.

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Dirk-Jan Faber (Victron Energy) ♦♦ david-hruska commented · Nov 20, 2023 at 08:12 AM

The first point I'll need to look deeper into.
For your second point. You do seem to have something wrong in your configuration. You have set your powers a thousandfold too high. Do notice the 'k'(ilo) Watt.

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Dirk-Jan Faber (Victron Energy) ♦♦ Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 20, 2023 at 10:32 AM

About the first point. At the moment this is considered normal behavior. When you hit minsoc we completely turn-off feed-in, which results in lower DC consumption (typically under 20W on a 3kVA). But when we reach Idle state during DESS we do not disable feed-in (we still want the limiting of AC input current to work, so we can't), so the consumption in DESS idle state is higher, around 35W on a 3kVA and of course more for larger units.

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koll commented · Nov 20, 2023 at 11:37 AM

Hello!

How can i add flexible grid fees to electricity price? I have 0,07 eur grid fee for daytime and 0,04 eur grid fee at night.

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Dirk-Jan Faber (Victron Energy) ♦♦ koll commented · Nov 20, 2023 at 12:04 PM

At the moment that is not possible yet. We'll put it on our todo list. Out of interest, which country and provider is this?

(Only one answer is needed. :))

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koll Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 20, 2023 at 12:12 PM

Estonia

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grua commented · Nov 20, 2023 at 05:27 PM

Hi,

which electricity price stock exchange index is used by DESS in the price formula for "p"?

The Austrian provider aWATTar uses the index “EPEX Spot AT”:

(https://www.awattar.at/tariffs/hourly)

The formula then reads as follows: (p + |p| * 0.03 + 0.015) * 1,20

I entered it like this because there is no possibility to use the absolute value of p in the formula, so the buy-price will be calculated wrong if p < 0:

So there are two questions:

Does DESS actually use the index “EPEX Spot AT” for “p” if Austria is specified as country or what other index?
"p" is actually sometimes negative. However, the 3% fee is always calculated fom the absolute value of p, i.e. |p| or ABS(p). Unfortunately, it is currently not possible to specify the absolute value of p in the formula. Can this be added?

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grua grua commented · Nov 21, 2023 at 03:56 PM

@Dirk-Jan Faber (Victron Energy) can you say something about my two questions above? In particular, the possibility of including the absolute value of p in the formula?

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Dirk-Jan Faber (Victron Energy) ♦♦ grua commented · Nov 23, 2023 at 08:47 PM

At the moment adding the absolute value in the formula is not supported. This is also the first provider I've heard about using it, but I'll create a ticket in our system for adding that. No promises on how quickly that gets picked up and added though.

As the source for the spot prices we use the API from ENTSO-E. All EU providers base their prices on this source. (https://transparency.entsoe.eu/transmission-domain/r2/dayAheadPrices/show)

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grua Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 24, 2023 at 10:52 AM

Many thanks @Dirk-Jan Faber (Victron Energy) for the answer and for creating the ticket!

aWATTAr charges both a fixed and a percentage margin on the energy price. Since the price often becomes negative, it is of course necessary to calculate the percentage based on the absolute value.

It would be very important that this possibility be implemented in the formula, as phases of negative energy prices are not that rare, especially in summer, and DESS would then calculate incorrectly at these times.

I'm almost certain that aWATTar will perhaps be the first, but certainly not the last, provider to come up with this idea :-)

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colin-jones commented · Nov 21, 2023 at 04:17 AM

In Australia, we have an option of dynamic 5 minute pricing for import and export. I plan to try setting up fixed hourly prices using historical monthly averages and experimenting a little.

I don't see any comments about handling of negative feed-in prices. Is it fair to assume that the model supports negative prices?

If so, does it curtail export by disabling solar controller export and limiting feed-in to zero, as per Fronius zero feed-in option ?

If not, is it possible to turn off Dynamic ESS during periods of negative feed-in price by mqtt or modbus, allowing normal ESS to manage battery charge, and then reactivate once prices have returned to positive, allowing Dynamic ESS to recalculate a new plan for the next 4 hours?

Regards

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Dirk-Jan Faber (Victron Energy) ♦♦ colin-jones commented · Nov 23, 2023 at 09:08 PM

I am aware of the Amber provider in Australia, though that one is probably not going to be supported directly by our system. The system is currently based on the hourly changing spot prices and adjusting that is not going to be simple.

The model does support negative feed-in prices (which happen every now and then over here). Feeding in will automatically be disabled when the prices are negative.

If you need, you can switch on/off Dynamic ESS on certain times automatically. I'd do that with Node-RED.

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colin-jones Dirk-Jan Faber (Victron Energy) ♦♦ commented · Nov 24, 2023 at 06:45 AM

Thank you.

I didn't expect you would want to play with the Amber api, when you have many other features to chase. I have updated to venus 3.12 and sorted a few issues in my drivers for aurora inverter and bms code. Plan to try 3.20 once 3.12 is stable and I am confident to overwrite the old backup partition.

I have put average buy/sell prices in beta vrm but couldn't enter a negative value. Feed-in is negative most days 1100-1500 during this half of the year. I can get the Amber prices in Home Assistant, so considering whether to utilize that or move the Amber API calls into my bms. Writing code v's risk of relying on HA.

I have been looking at turning off at Settings/DynamicEss/Mode. Never played with Node-RED. I probably should put some time into it. I also need to use Aurora remote control to shut it down as it doesn't have any power limiting features I can write to.

I was planning to experiment with the Schedule/n/AllowGridFeedIn when the real five minute price was negative, where n is usually 0 ( but could sometimes be 1,2,3)

Regards

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gdhondt commented · Nov 21, 2023 at 06:36 AM

My DESS give a alarm. Dynamic ESS no matching schedule IMG_5456.png

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meyo084 gdhondt commented · Nov 21, 2023 at 07:12 AM

Same situation over here.. looks like a server side problem

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meyo084 gdhondt commented · Nov 21, 2023 at 07:58 AM

Fixed by rebooting GX..

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Henrik Känngård meyo084 commented · Nov 21, 2023 at 08:12 AM

Still same problem after reboot here.

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dmsims commented · Nov 21, 2023 at 10:48 AM

When entering time schedules how do you enter for example 23:30 - I cannot get it to accept any input ?

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screenshot-2023-11-21-104433.png (23.5 KiB)

Dirk-Jan Faber (Victron Energy) ♦♦ dmsims commented · Nov 21, 2023 at 11:21 AM

At the moment the system is based on hourly changes in price. The way to work around that limitation right now is to use the average price for the transitional hour.

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juelo commented · Nov 22, 2023 at 03:51 PM

I would suggest to add an extra button in dashboard control section, additional to Auto, Buy, Sell, Off.

Lets call it: Standby

In Standby-Mode I would like to see all the different graphs and simulation for the DESS in the dashboard. Calculations should be made according to your algorithm and time schedule but:

Leave all the parameters for SOC, Charge or feed-in the live-system like in OFF Mode.

So I can check the DESS-System and can change some parameters to see how it would change the resulting planning/doing of the DESS without immediately resulting in real live changes on my system.

Yes there would be some deviations compared to the live Auto-System running.

But for checking and testing before switching to Auto-Mode (for me) it would be interesting/helpful.

Best regards

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ojack commented · Nov 27, 2023 at 08:55 PM

It would be great if DESS would record grid buy price even if it's set to off.

This would help me to calculate if DESS could be a profitable feature for me.

At the moment, prices in Germany seem to be developing in such a way that a fixed annual tariff could be cheaper than a dynamic tariff. If the PV is large enough, you only need it when the weather is bad and that's exactly when even the lowest price per day is almost as high as a fixed price. Unfortunately, with a few% losses, DESS would often be useless here.

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ronaldt commented · Nov 27, 2023 at 10:31 PM

Using Nod-Red DESS and it looks very promising. The only thing that completely ruins the behaviour/prediction is when I charge my car. The amount of energy compared to the usage of the house is way higher. My normal way of charging the car is schedule it to charge on times when the energy price is low directly from the grid. I made a small Node-Red flow to make sure that the energy is taken from the grid when I use scheduled charging (with a Victron EVCS). See attached file.

My suggestion, as a first step, would be that when scheduled charging is used then do not take this amount of energy into the prediction calculation of DESS. The best would be if we could indicate in Venus that we want scheduled charging from the grid (and not from the battery) then this would make a (part of) the solution how to handle the energy taken by the car in a DESS situation.

EVCSfromGrid.txt rename .txt into .vcsf or paste content directly into Node-Red input.

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evcsfromgrid.txt (9.1 KiB)