tubeman avatar image
tubeman asked

Peak shaving while charging from grid

I am looking at buying a Multiplus 48/3000/35-32 with the GX controller to combine with a 16kWh BYD battery and solar panels. I looked through the documentation but could not find information on my use case.

One of the reasons that I want to buy this setup is to do peak shaving. From what I understand from the documentation, the default setting is that you do ‘peak shaving’ when the battery is full but that it will shave to (close to) 0W. When the battery is depleted, peak shaving will stop and you will go to the grid for 100% until the PV charges the battery again or you specify a charging window from the grid after which it will resume.

The issue I have with this setup is that (most probably) next year, we are going to be taxed based on the maximum power demand from the grid in a 15 minute window over a month. So using 10kW during 15 minutes anytime in the month will determine the amount we are taxed and each higher peak value will be much more expensive than the lower one. The goal for the peak shaving would be to reduce this maximum peak but when the battery would be depleted early in the afternoon, generating a single high 15‘ peak in the evening at any time during the month will make the battery investment worthless for this purpose.

I did find that you can set the grid power but that seems to always apply and in December for instance, I have days that only 10kWh is used at the moment but also days with 50kWh. Setting the grid parameter to 2kW would mean that the battery is not used at all during the 10kWh day but would still be depleted after a few hours on the 50kWh day in turn causing a power peak once the battery is depleted. As the goal is also to use the battery to charge during the off-peak hours and use that energy during the day, not using the battery on the 10kWh day will negate the benefits of the cheaper off-peak energy cost.

My question now is: is there a way that you can set a certain limit (e.g. 40% charged) after which the battery starts charging from the grid at e.g. 3kW up to e.g. 70% but when there is a total power request from the grid of e.g. >6kW during the charging, it will kick in and deliver the requested power above 6kW and starts charging to the requested limit again once the power drops below 6kW? When the charging is done, it can return to 100% peak shaving to (close to) 0W down to the 40% level at which the charging starts again. In short, I want to set a limit on the power drawn from the grid at all times and the battery would have to do peak shaving when the demand is higher and charge itself (from the grid if there is no PV) to a certain level when there is less demand while still offering the peak shaving during the charging.

If this can be done through an API or other interface that would also work but (again, from what I understand) the battery would not be used at all during a charging window which might again lead to peaks while charging which is what I wanted to avoid. If this is not possible now, do you think this is something that can be included in a firmware update in the future as for the Belgian market this would be an extemely useful feature starting next year?

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

frederikna avatar image frederikna commented ·

I am looking for the same solution, to have control on the peak shaving option. I think this is a feature that is needed in the future to support Belgium customers.

0 Likes 0 ·
4 Answers
Alexandra avatar image
Alexandra answered ·


With ess you can set times windows for battery charging as well as SOC to stop at if it is reached before the time ends.

you can set your amps from grid charging lower so you keep your current draw down as well when programming the multi.

And you can set your input current to a limit as well for the whole system.

Are you using solar as well? And just a comment on the 50kw not sure a 3kva would be able to do that in a day you may need to look at going up to a 8kva multi. Unless you were using the 6kwh as an example

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

multivictor avatar image
multivictor answered ·

I have the same problem. (limit the scheduled charges to max. 2.3 kW (because the grid peak penalty starts above 2.5 kW).

In ESS "Scheduled carging" I can set time windows to charge and limit the SOC but there is no option to set a limit to the AC coming from the grid to the battery.

In ESS there is idd a limit feed in towards the grid but not from the grid towards the battery (if there is so, I can't find this option).

When the battery (BYD LVL 15.4 kWh) charges from the grid (scheduled or automatic when 24 hr under lower SOC) it always charges at 16A. Instead of peakshaving the system creates its own peak (governemental grid peak limit is 2.5 kW of 10/11 A).

If there is a way in ESS tot limit the grid feed in towards the battery (not towards the AC consumption) where can I find this option (scheduled charging or automatic charging via battery life).

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Stijn Dhondt avatar image
Stijn Dhondt answered ·

Maybe i am quite late with my anwser here but!

I am using node red within Home assistant and manually for the moment am setting the SOC limit as a was to lazy to automate that. But with the setting gridsetpoint i am controlling the amount of power that is being used from the grid, and it is working out like Belgium actually wants us to limit our usage.

4 months of automatic control without even looking at the grid. Only thing i still need to automate is the SOC limits coming and going into winter periods.

So if you guy's want help or the code just ping me ;-)


2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

stefdewilde avatar image stefdewilde commented ·
Hey Stijn, willing to share how you did it?

Also Belgian and also want to prepare for the whole capaciteitstarief :)

0 Likes 0 ·
bertcalewaert avatar image bertcalewaert commented ·
Hi Stijn,

I am a HA user but not (yet) a NodeRed user. Could you give me more info on how you did it.

For the moment I'm filling my batteries at night 'full force' by setting the SOC at a high level (during winter months), but as of 2023 I will have to do this in a controlled way... extra challenge: EV Charger...

0 Likes 0 ·
philippec avatar image philippec commented ·

Hi Stijn,

Like presumably many others in Flanders I am looking at how to prepare for the "capaciteitstarief", and your approach seems very interesting.

I use HA and have Node-RED up & running, so all I now need is... your code ;-)

Very much appreciated in advance!


PS: I put together a very basic "Live PIEK Alert" automation that broadcasts alerts to train (?) the family, but obviously preventing would be far better (and less irritating?). [green: 0 to 2.5; orange to 3.15]


0 Likes 0 ·
live-piek-alert.jpg (17.0 KiB)
frederic avatar image frederic commented ·
Hey Stijn, ook in België... Zou je mij ook de code kunnen doorsturen?
0 Likes 0 ·
Stijn Dhondt avatar image
Stijn Dhondt answered ·

Seems i left you all behind without answering but this thing is still growing and time has been very short at hand the last year. Bellow is the flow i am using for now. But still want to move from my color control GX to the Cerbo's large image as this one had Node red built in.


I have been moving from node red to Home assistant automation and back just as this thing has so much options that Home assistant just simply does not offer. Also trying to move to the hourly rates has been on my mind for months but as the rates now don't fluctuate with more than 10cents a day this just does not make sence anymore.

So for now waiting on my Cerbo to continue this story. ;-)

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.