Finally figured it out - Home Energy Manager + Mobile Charger Connect + Solar

[Gubab]

Craig or somebody else who has this working: Could you tell me if the sensors for the photovoltaic system should display positive or negative amperes? I got the additional sensors for the PV installed yesterday, but in the web application ( first page - the picture showing the current flow) there does not show up any current from the PV although the three sensors of the PV show a positive ampere current on the web page "Homeinstallation/ Senors".

Kind regards

Burkhard

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[kamil]

Picked up my MY22 Taycan RWD a couple of weeks ago, and had the Porsche Mobile Charger Connect (PMCC) and Porsche Home Energy Manager (HEM) installed at my house the same day - but I only figured it all out (finally) this morning, and got it to work the way I wanted.

Issue: I have a 10 kW solar system on my rooftop, including a 13 kWh battery. On a good day, the battery would be fully charged by noon, so the system is spitting out up to 10 kW, with my household using typically just around between 1 kW and 2 kW of that generation. Of the amount generated, there is a limit of 5 kW that I can export/send to the grid (at a miserly 6.7c per kWh), so the remaining solar generation is just wasted.

My ideal system: PMCC + HEM would charge the Taycan using the excess solar energy, and not draw power from the grid at all unless I need the car to be charged in a hurry.

Problem: For the past two weeks -

• using profile alone (min 65%; optimised charging selected) - the car would simply charge to 65% on fully blast (7.5 kW on my single-phase system) and then stop charging completely;
• using profile + timer (min 65%; optimised charging selected; timer 85% at 16:00 hrs) - the car will do as intended ... charge to 65% and then pause, and then wait until the last possible moment to charge on full blast (7.5 kW) to get to 85% at 16:00 hrs [interesting side note - on timer, the charging starts at the last possible moment, rather than earliest possible moment]

This is not what I want. The system is drawing from the grid (to make up the 7.5 kW when there is insufficient solar generation) to charge the car in a short period, when I don't need it to do that. I'd prefer the car to charge slower, and just using my excess solar energy.

And then ... I finally figured out what I have been doing wrong (or not doing) ...

It's this little setting called "Activate Plug and Charge", hidden under the settings menu, which I had not come across earlier. This is the final step that I have not been doing to make it all work!

To access it - you go to <Home> - <Charging> - <Overview> - < ... > - then select "Activate Plug and Charge". And voila! Suddenly, the PMCC is talking to the car to vary the charging current continuously, and only use as much as there is excess solar, to charge the car.

Problem solved! I thought I would share this - I wish Porsche would create a step-by-step guide to make this more intuitive. I have been trying to figure this out, and it has taken me a while. But I'm happy - it's working for me now!

Current setting:

• Location-based profile around my house - min 65%, optimised charging selected
• Timer - charge to 85% target by 16:00 hrs each day, repeated
• Plug and Charge "activated".

Cheers
Craig in Melbourne, Australia

Thanks @craig3101

This is an excellent article that I came across in a while. I have a Taycan Turbo MY21 With HEM installed. I am far from getting the above working since I think there are some major shortcomings in the installation by the electrician.

Nevertheless, I am Based in Beirut, being part of the Middle East Region, the My Porsche App is still not working. So I am guessing the "Plug and Charge" Feature referenced above is only available from within the APP. I tried looking for it within the HEM Web Application and PMCC Web Application, but couldn't find such a feature to be enabled.

the closest in reference was the "Self Consumption Optimization", under the Optimized Charging, Energy Manager Tab, within the HEM Web Application.

So my question to you, the Self-consumption Optimization was switched "on" within the HEM Web Application, and still the desired outcome of charging the car with the excess energy from the PV didn't materialize until you enabled the " Plug and Charge Feature" within the MyPorsche App?

Thanks in Advance

Cheers,

 

[AndiL]

@kamil You need to enable "Plug and Charge" in the PCM of the Taycan itself.

 

[kamil]

@kamil You need to enable "Plug and Charge" in the PCM of the Taycan itself.

@AndiL that worked, even the solar sign within the PMCC charger was showing. yet the below problems remained:
1. within the HEMS Web Application, overview section, the flow is showing the combined total from the Grid and the PV. To illustrate it with numbers:
- the current flow should only be showing 3KW coming from the PV.
- The Total energy going to the EV is 5KW (the remaining 2 KW are coming from the grid)
- Yet the energy Flow is showing 5KW from the PV, and 2 KW from the Grid while the overall consumption of the EV is 5KW.
- which means the HEM is not taking the excess energy, only. but rather its consuming the additional Energy needed from the Grid.

PS. I have 6 sensors, the 3 that came with the HEM and I ordered an additional 3. but that was way before going through this thread and now I have all 6 sensors, yet without reaching the desired solution which is charging the extra power from the PV to charge the EV.

by the time I got this partial solution it was already heading towards sunset, will give it another go this week to see if any progress is made, but based on what I read, I wasted a good sum of money roughly 500$ for 3 additional sensors that are of no use.

 

[Gubab]

kamil,

i am also struggling since December with my HEMS. This is what I can contribute: You do need the additional sensors for you Photovoltaic. I tried with 3 sensors only - it did not work. I contacted Porsche. I received a written information from Porsche Germany that the additional 3 sensors are necessary. So it was not wasted money but necessary to buy the 3 additional sensors. When I now connect the car and my PMCC is connected via WLAN and sun is shining, then the Taycan is charging as it is supposed to. Charging speed is regulated depending on Photovoltaic current. But my HEMS web interface is not showing any Photovoltaic current. I do not know why the web interface is not showing the right currents. So please check with your PMCC what the actual charging current is ( the left information button - while charging) and you might see that the PMCC is working as it is supposed to, but the web interface is not displaying everything correctly. When I look at your picture I wonder why you are using CT5, 6 and 7. If your first three sensors are CT 1,2 and 3 then what is CT4 measuring? Maybe some sensors got mixed up?
Kind regards
Burkhard

 

[kamil]

kamil,

i am also struggling since December with my HEMS. This is what I can contribute: You do need the additional sensors for you Photovoltaic. I tried with 3 sensors only - it did not work. I contacted Porsche. I received a written information from Porsche Germany that the additional 3 sensors are necessary. So it was not wasted money but necessary to buy the 3 additional sensors. When I now connect the car and my PMCC is connected via WLAN and sun is shining, then the Taycan is charging as it is supposed to. Charging speed is regulated depending on Photovoltaic current. But my HEMS web interface is not showing any Photovoltaic current. I do not know why the web interface is not showing the right currents. So please check with your PMCC what the actual charging current is ( the left information button - while charging) and you might see that the PMCC is working as it is supposed to, but the web interface is not displaying everything correctly. When I look at your picture I wonder why you are using CT5, 6 and 7. If your first three sensors are CT 1,2 and 3 then what is CT4 measuring? Maybe some sensors got mixed up?
Kind regards
Burkhard

HI Burkhard,

As it turns out, I have 9 censors:
- 2 sets of sensors connected to the Power Source(s):
3 censors connected to the PV
3 Censors connected to the Grid
- One more set of 3 sensors connected to the Power Consumers (the EV).

so in total 9 censors. so from what I read, I guessing the electricians were not up to par to say the least. so probably 2 sets of sensors are needed, I just didn't figure out yet, where they should be placed. My technical know-how in this is very limited, so I am acquiring it by experience in addition to this Forum (which is proving to be very rich). I am attaching a couple of more screen shots, hope they give more insight into may current layout.

Ps. I wouldn't worry about the values showing unable to measure since, currently I am on General Model and without any sunlight and low utilization of electricity its not reflecting any numbers. during the day we can see all the 9 censors data showing.

Regards,
Kamil

 

[Gubab]

Hi kamil,

my technical knowledge is very limited too and i too have 9 sensors. Please post a picture of the 9 sensors, once the PV-Sensors are measuring during sunlight and the car is charging and maybe one picture, when you are charging the car from the grid. Do you have a solar storage (like Tesla Powerwall which makes my setup a little more complicated) ?
Regards

 

[kamil]

Hi kamil,

my technical knowledge is very limited too and i too have 9 sensors. Please post a picture of the 9 sensors, once the PV-Sensors are measuring during sunlight and the car is charging and maybe one picture, when you are charging the car from the grid. Do you have a solar storage (like Tesla Powerwall which makes my setup a little more complicated) ?
Regards

Will do Burkhard.

I should get my car from the service this week, so probably during the weekend I should have all the pics in place. I have 7 batteries, Power cube H1, 24KW of power storage, and a 10K hybrid inverter. At peak time I get 7KW through the solar panels, which charges the batteries quite fast. so usually by 10-11 am my batteries are fully charged and all the excess is power is gone to waste. (PS. we have a lot of blackouts in Lebanon, so the Grid is not available for more than 2-3 hours during the day, and another 4 hours at night).,

The ideal scenario would be to charge the EV with all the excess power once the batteries are full. will revert with the above to compare notes.

Cheers,
Kamil

 

[Gubab]

Kamil, i have a tesla power wall. I also experienced that the pmcc will not take the pv energy only but sometimes takes additional energy from the storage or the grid for charging the car. I think the pmcc tries to keep current at the grid sensors zero. So when there is a cloud it continues charging with the same current from the storage and only downregulates charging when the storage is empty. I can prevent this by „locking“ the powerwall. The PMCC will downregulate charging if the grid sensors measure energy coming from the grid. But since they start measuring with my sensors at a current of 3 Amperes upward, there is some energy coming from the grid (1-2 kW) up to this point of time when 3 Amperes is exeeded at the grid sensors. I look forward to see the pics of your sensors!

 

[AndiL]

I think the pmcc tries to keep current at the grid sensors zero. So when there is a cloud it continues charging with the same current from the storage and only downregulates charging when the storage is empty.

This is correct. Also charging should never instantly stop and restart just a few seconds later again. So there is always some kind of timeout implemented for powering down and powering up again. The PMCC requires the HEMS to submit PV surplus for at least 30 seconds before it wakes up the EV.

 

[Gubab]

Finally everything is working thanks to Craig and AndiL who was very helpful with sorting out the currents of my sensors!

The Pitfalls:

- If the car has a 22kW charger and your home installation can take only 16A you will need three additional sensors ( if you have 3 phases) on the lines to the PMCC to limit the current to 16A. Once the PMCC is communicating with the HEMS you can not limit the maximal current of the PMCC, the HEMS will send 22kW to the car when charging from the grid and the fuse will blow unless you have these additional sensors on the lines to the PMCC, where you can configure a maximum current.

- if you want to use Photovoltaic you will need 3 additional sensors ( if you have 3 phases) on the photovoltaic lines.

- you always need the 3 sensors for the grid ( if you have three phases), only three sensors are included with the HEMS package - you need to order 3 ( for PV) or another 3 sensors ( if you need to limit the current going to the PMCC - e.g. if your car has a 22kW charger and you have a 16 Ampere home installation)

Look at the web interface of the HEMS and check the sensors:

1. When there is no storage connected: The sensors for the grid must display negative Ampere numbers when current is flowing from the grid to the car. There should be positive numbers when the current is flowing from the photovoltaic system to the grid. The sensors should not measure a current if the car is charging from the PV.
2. Sensors for the Photovoltaic must display negative Ampere if the sun is shining. My photovoltaic sensors were installed in the wrong direction ( they showed positive Amperes and, the HEMS interface did not show any current coming from the photovoltaic). The photovoltaic dependent charging worked nevertheless even with the PV sensors in the wrong direction, since the current going to the car is regulated by the grid sensors ( they try to keep the current at zero). But you will have to configure the PV sensors. If you don`t, the PV depedent charging of the car will not work.
3. The sensors for the line to the PMCC will show negative Ampere when the car is charging

If you have a storage ( like Tesla Power wall) that is connected via one phase it gets a little more complicated. If the powerwall is being discharged with 4,9 kW ( 20 Ampere) on phase 1 these 20 Amperes will add on positive on phase 1. So the car is drawing -6 Ampere on phase 1, 2 and 3. The Grid sensors for L2 and L3 may show -6A. And L1 is displaying +10 A: -6 ( car) +20 (Tesla Power wall)- 4(for house electricity). First i thought that the L1 sensor is placed not correctly, but Andi pointed out to me, that the current of the storage will add on on this phase. And if the powerwall is being charged with 4,9 kW there will add -20A on Phase 1.

In the morning ( powerwall empty) the PV of phase 1 is going to the powerwall, phase 2 +3 are going to the car ( 2/3 of the PV). Once the powerwall is ful, there may be small amounts < 3 ampere go to the grid until the grid sensor measure a current above 3 A and upregulates the current of the PMCC. When the sun is decreasing, the PMCC will draw current from the powerwall. If powerwall is empty or locked, there will be small amounts (<3 ampere) of current come from grid until the grid sensors measure a current > 3 ampere and downregulate the current that the PMCC will send to the car.

Timers don´t seem to stop the photovoltaic dependent charging. Has anyone figured out how to stop the charging at SoC 85%?

 

[AndiL]

The Taycan will charge via PV surplus always until it is full. The HEMS does know the SoC (it is provided), but Porsche did not implement any setting to limit PV charging either in the HEMS or in the Taycan itself. Both would technically be possible.

 

[Electroad]

Picked up my MY22 Taycan RWD a couple of weeks ago, and had the Porsche Mobile Charger Connect (PMCC) and Porsche Home Energy Manager (HEM) installed at my house the same day - but I only figured it all out (finally) this morning, and got it to work the way I wanted.

Issue: I have a 10 kW solar system on my rooftop, including a 13 kWh battery. On a good day, the battery would be fully charged by noon, so the system is spitting out up to 10 kW, with my household using typically just around between 1 kW and 2 kW of that generation. Of the amount generated, there is a limit of 5 kW that I can export/send to the grid (at a miserly 6.7c per kWh), so the remaining solar generation is just wasted.

My ideal system: PMCC + HEM would charge the Taycan using the excess solar energy, and not draw power from the grid at all unless I need the car to be charged in a hurry.

Problem: For the past two weeks -

• using profile alone (min 65%; optimised charging selected) - the car would simply charge to 65% on fully blast (7.5 kW on my single-phase system) and then stop charging completely;
• using profile + timer (min 65%; optimised charging selected; timer 85% at 16:00 hrs) - the car will do as intended ... charge to 65% and then pause, and then wait until the last possible moment to charge on full blast (7.5 kW) to get to 85% at 16:00 hrs [interesting side note - on timer, the charging starts at the last possible moment, rather than earliest possible moment]

This is not what I want. The system is drawing from the grid (to make up the 7.5 kW when there is insufficient solar generation) to charge the car in a short period, when I don't need it to do that. I'd prefer the car to charge slower, and just using my excess solar energy.

And then ... I finally figured out what I have been doing wrong (or not doing) ...

It's this little setting called "Activate Plug and Charge", hidden under the settings menu, which I had not come across earlier. This is the final step that I have not been doing to make it all work!

To access it - you go to <Home> - <Charging> - <Overview> - < ... > - then select "Activate Plug and Charge". And voila! Suddenly, the PMCC is talking to the car to vary the charging current continuously, and only use as much as there is excess solar, to charge the car.

Problem solved! I thought I would share this - I wish Porsche would create a step-by-step guide to make this more intuitive. I have been trying to figure this out, and it has taken me a while. But I'm happy - it's working for me now!

Current setting:

• Location-based profile around my house - min 65%, optimised charging selected
• Timer - charge to 85% target by 16:00 hrs each day, repeated
• Plug and Charge "activated".

Cheers
Craig in Melbourne, Australia

 

[Electroad]

Craig, a fellow Aussie here. I have done everything recommended in your post, but cannot make my car charge from solar power production when it is available, as it is right now! I would dearly love to use the cheapest power to trickle charge. My Taycan, the whole reason I purchased the HEM. However I configure the timer and general profiles, insists on charging my car at close to the full 11 kW which on a sunny day means 40% solar and 60% from grid, pausing to do this until last moment necessary to charge at this max rate. What it should be doing at the moment is feeding all of the 3.1 kW going back to grid to the car. I attach screenshots from my HEM manager and profiles. And, yes, plug and charge is enabled. Any ideas from anyone most welcome.

 

[Gubab]

Electroad,
do you have a Porsche Mobile Charger Connect (PMCC)? Does it show the photovoltaic Icon and the HEM icon on the display while charging and sun is shining? Check in the PMCC whether it is connected via WLAN ( or PLC) to your HEM! It seems the HEM is measuring the PV correctly (which my HEM did not) but does not talk to the PMCC.
kind regards
Burkhard

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