EV Charging Station support for load control ("netzdienliche Steuerung?") §14a EnWG in Germany

Question

question

spacecow asked Mar 18, '24

EV Charging Station support for load control ("netzdienliche Steuerung?") §14a EnWG in Germany

Hello,

I think about installing an EV Charging Station NS and since 1.1.2024 according to §14a EnWG controllable loads like Heatpumps and Wallboxes need the possibility to be controlled by the grid provider to limit the total load to 4.2kW. The simple solution is a Contactor controlled by ripple control (Rundsteuerempfänger) but this is not real desired. Is there any preparation (input contact to limit current to eg. 6A if contact closed (like for some heatpumps) to make the EV Charging Station operational als a controlled load as seen by §14a.

Has somebody Experience with this, and already a Wallbox connected in Germany after 1.1.2024.

Thanks in advance

Björn

ev charging station balanced ac-load

1

2 |3000

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

matt1309 commented · Mar 18 at 10:23 AM

I'm not aware of physical sense wire circuit but could do something with software/modbus communication device to drop EVCS charging current rate.

How does the grid provider activate the switch? If you know how they send the activation message to the ripple control then i imagine it wouldnt be too difficult to pull something together in something like node red that acts the same but send message to evcs via modbus tcp rather than a phsyical sense wire

0 ·

Modifications Space

Node Red Space

Answer 1 · 2024-03-18T16:39:29Z

spacecow answered · Mar 18 at 04:39 PM

Thanks, that this is possible with some home automation was expected (I am using FHEM and think I can code this) but the question is if the grid provider will accept this. And unfortunately the grid provider (Regionetz in Aachen) is not reacting to my request except for a "we should discuss this".

Thus I was curious if somebody did already something that was accepted by the grid provider

1

2 |3000

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

matt1309 commented · Mar 18 at 05:12 PM

Ahh that's a shame.

How does the grid provider activate the ripple control. Is there a way in which you could make your home automation appear to be a ripple control. ie from their point of view it's identical to ripple control but on your end it adjusts limits via modbus tcp rather than physical sense wire connection?

If the ripple control documentation is online maybe you could make your home automation api look the same as ripple control. That way they'd never even know.

Not the answer you're looking for just throwing ideas out there. I'd offer to lend a hand on the code side, but perl isn't something i've messed with before.

0 ·

Answer 2 · 2024-04-04T13:06:52Z

spacecow answered · Apr 04 at 01:06 PM

I finally got an reply from my grid provider: They don't know how the control will be done. End of the year I will get a "Controllbox" which will have either a modbus output or a relay output but they don't know the details.

1

2 |3000

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

matt1309 commented · Apr 04 at 02:19 PM

That's a shame. Definitely sounds like something you could integrate via node red/home automation system but hard to know when they dont even know

0 ·

Answer 3 · 2024-04-07T13:38:05Z

Daniel Weber answered · Apr 07 at 01:38 PM

Hi all,

i´m facing the same problem in the near future at a customers site.

In germany we have since 1st January 2024 the new grid stabilizing rule/law by EnWG §14a to reduce the electrical load of HVAC-pumps (sum of all hvac-pumps) and wallboxes to a max. of 4,2 KW if the grid gets in unstable conditions. House or pv installations are NOT affected by this rule/law!

Therefore the power providers have set up measurement concepts with 2 grid smartmeters in serial. The 1st, from grid seen, is the smartmeter for the HVAC-pumps and/or wallboxes (so called "controlable Device" or sVE in the attached picture) and the second one is for the rest of the house installations and PV. If the pv has excess energy ,more then the house needs, then the excess is also used for the 1st smartmeters loads and if not needed the rest is fed into the grid.

The price for KWhours on Smartmeter 1 is lower then on Smartmeter 2.

I would like to place a feature request to VE.

To realize EnWG conformity with a hardware contact from the power provider (a simple contact with no/nc, comes with coupled HF-signal via gridline) i need an input at the gx-device with a programmed function behind like this:

"reduce consumption from grid to max. 4,2 KW if input at gx-device is low (nc)

AND

if PV is available, more then reduced loads needs, charge the car by VE-standard charge programm (6A, 10A, 16A, etc).

I will say, reducing HVAC-pumps could be done by a gx-device (if VE see´s an advantage!) but could also be done separatly.

I also need the possibilty to select "charge now! (whatever (grid/pv/reduction) is available!)" , "charge -green- with pv-only" next to the timeselected charge.

Thank for reading!

regards,

Daniel

Spelling and grammar mistakes are for free!

mk3c.png (441.4 KiB)

1

2 |3000

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

spacecow commented · Apr 08 at 01:11 PM

Hej,

I have a similar setup also my Messkonzept is No. 8 (MK8) but its more or less identical except for the power sensor. I think reduction of the EV Charger can be done by modbus, also with 3 Phases the minimum load is 4.14kW so for me I have either limit the EV Charger to 6A and switch off the Heatpump or to switch to 1 Phase for the EV Charger. Does anybody know a way to add the 3P/1P switching w/o voiding the warenty. Maybe even add an external contactor for L2 and L3 and only put the control from the relay outside, or even control the contactor for L3 and L3 via modbus and keep the hardware unaltered.

greetings

Björn

0 ·

Answer 4 · 2024-04-08T06:43:47Z

jochenku answered · Apr 08 at 06:43 AM

Hi Björn,

my understanding of the present requirements regarding EVCS approval in Germany are slightly different.

Even in 2024 it is still possible to install charging points with <= 11 kW (either max or derated power) without approval, only information is required (anmeldepflichtig).

Charging points > 11kW require approval, except if the charging point is externally controllable, then again only information is required.

So if you do not need the external contrallability together with the added complexity (in order to participate from reduced grid fees sometime) basically nothing has changed compared to 2023.

Best regards, Jochen

1

2 |3000

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

spacecow commented · Apr 08 at 12:53 PM

@JochenKu as far as I understood both the regulation as also the discussion with the grid provider, every controllable load (Heat Pump, Wallbox) installed after January 2024 falls under this regulation. But you can just install it till the end of the year they don't know how to implement the control to limit the power down to 4.2kW. So as soon as I get my electrican I will get this installed and wait how this grid controll will be done in the future but as I will connect it to the cheap meter for Heatpump I will need to get it complain with this controle as soon as they know how to do this.

0 ·

question