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

[craig3101]

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

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[AndiL]

Thanks @craig3101

So for your setup, it charges with full speed to 65%. After that it only uses excess solar energy to charge to 85%. If it can’t reach 85% until 16:00 hrs, it would charge with full speed. Is this correct?

Would you be interesting in testing something? If you don’t use a timer, would it still charge with excess solar energy after reaching 65%?

Thanks,
Andreas

 

[Gubab]

craig3101, thank you very much for your report,

can you confirm, that after reaching 65% SOC the Porsche Home Energy manager is regulating the charging current depending on you momentary solar excess energy until reaching 85% SOC?
Kind regards
Burkhard

 

[craig3101]

Thanks @craig3101

So for your setup, it charges with full speed to 65%. After that it only uses excess solar energy to charge to 85%. If it can’t reach 85% until 16:00 hrs, it would charge with full speed. Is this correct?

Would you be interesting in testing something? If you don’t use a timer, would it still charge with excess solar energy after reaching 65%?

Thanks,
Andreas

Hi @AndiL

I think you are right in relation to your first point - it will charge at full speed to get to 85% for the timer.

I just tested your request. So, I turned off the timer this morning (battery was showing SOC at 86% - note: it charges "over" the set level by 1 or 2%, don't know why). As soon as the sun came up and the solar started generating, my car started charging again, at the variable level. However - I just noticed that the system is saying "charging session completed" at 90%. Not sure if that's the factory setting, but I'll continue to follow up and update.

Cheers
Craig

 

[craig3101]

craig3101, thank you very much for your report,

can you confirm, that after reaching 65% SOC the Porsche Home Energy manager is regulating the charging current depending on you momentary solar excess energy until reaching 85% SOC?
Kind regards
Burkhard

Hi Burkhard @Gubab

I can confirm that you are absolutely correct. Once the car's battery reaches my minimum setting for my "home" profile (65%), it started charging on variable current to reflect my solar generation.

See my reply to @AndiL above - when I turned my timer off, with only the "home" profile active, the car continued charging until it reached 90%, and then stopped. I don't have a setting for it to stop at 90%, so I'll watch the system and see if it does this consistently with only the profile active (without any timer).

Cheers
Craig

 

[Gubab]

Craig,
thank you very much. So you managed to be the first person who got this PV- depentend charging with Porsche HEM to work and describes this on a forum. Congratulations! This makes me very happy, since i was looking for a solution for some time ( my Taycan will arrive in March) I might come back to you if i need help with configuration of the web application of the HEM. Or would you mind posting some screenshots? Kind regars and wish you a lot of sunny hours in 2022!
Burkhard

 

[craig3101]

Craig,
thank you very much. So you managed to be the first person who got this PV- depentend charging with Porsche HEM to work and describes this on a forum. Congratulations! This makes me very happy, since i was looking for a solution for some time ( my Taycan will arrive in March) I might come back to you if i need help with configuration of the web application of the HEM. Or would you mind posting some screenshots? Kind regars and wish you a lot of sunny hours in 2022!
Burkhard

Hi Burkhard - please feel free to check in again when you get your car. The HEM configuration is quite simple and doesn't require many parameters - just a couple of ticks ("prioritise PV" and "cost-optimised charging") from memory. See video attached of how the system is self-adjusting the current sent to the car battery (note: it's a very cloudy day haha).

Cheers
Craig

 

[AndiL]

@craig3101 thanks for the video. That Intervall is quite fast.
Would you mind posting a screenshot of the available settings? I have been looking for a documentation of those for a while and sadly found nothing.

Thank you,
Andreas

 

[craig3101]

@craig3101 thanks for the video. That Intervall is quite fast.
Would you mind posting a screenshot of the available settings? I have been looking for a documentation of those for a while and sadly found nothing.

Thank you,
Andreas

Hi Andreas - these are some of the settings. Hope it helps!

cheers
craig

 

[AndiL]

This is brilliant, thank you @craig3101 !

 

[craig3101]

Hi @AndiL

...

However - I just noticed that the system is saying "charging session completed" at 90%. Not sure if that's the factory setting, but I'll continue to follow up and update.

Cheers
Craig

Hi Andreas - in relation to this point (of charging to 90%, then stopping), I have trouble-shot this. I don't believe it's in the settings - it should charge to 100% before stopping.

I think what happened was that the PMCC lost its connection with the HEM (this happens sometimes - and I just do the usual reset of turning both PMCC and HEM off and then on again), and so it just stopped charging. I re-established the connection when I saw the error messages, and it just re-started and charged to 100%.

Cheers
Craig

 

[AndiL]

Is the PMCC connected via WLAN or via PowerLine? If WLAN, you may want to switch to PowerLine instead. When the WLAN router is updating the frequencies used, PMCC will have problems getting a connection quickly. And EEBUS requires a steady connection as it pings the device once a second. I had these issues quite often, once I switched to PLC I never had any disconnects again.

P.S.: I am developing an open source charging software https://evcc.io/ which also supports EEBUS. (So I can charge my Taycan without the Porsche HEMS)

 

[craig3101]

Is the PMCC connected via WLAN or via PowerLine? If WLAN, you may want to switch to PowerLine instead. When the WLAN router is updating the frequencies used, PMCC will have problems getting a connection quickly. And EEBUS requires a steady connection as it pings the device once a second. I had these issues quite often, once I switched to PLC I never had any disconnects again.

P.S.: I am developing an open source charging software https://evcc.io/ which also supports EEBUS. (So I can charge my Taycan without the Porsche HEMS)

Thanks Andreas. Is there a "dummy's guide" to connecting to PLC? I tried to connect via PLC but don't understand where the PLC modem is? I have downloaded the manual from Porsche, but as usual, the information is very sketchy and doesn't help me.

FWIW - my WLAN connection is now relatively stable. The PMCC is connected via the HEM Hotspot so it is connected directly, rather than via my wifi router.

Cheers
Craig

 

[AndiL]

Craig, both devices have a build-in PLC modem. So as long as the cable distance from the HEMS to the PMCC is not too long, they will find each other.

To test simply turn on the PLC Modem in the HEMS and click on Connect, see https://www.taycanforum.com/forum/t...-plc-connection-to-pmcc-help.7334/post-105084
Then go to the PMCC device, parallel to the wifi settings there is a PLC menu offering to pair to another PLC device. Select that and you should be able to connect the two devices. Beware that that process is not running forever and times out after a minute or two.

On success you can disable the WIFI on the PMCC and both devices should now reconnect over PLC for the EEBUS connection and you should see the same icons on the PMCC on the top left again. Some warnings about failures may appear saying you might need to go to the dealership, just ignore them.

Hope this helps,
Andreas

 

[Gubab]

Craig,
are you using a solar battery for storage of energy in your house (like tesla Power Wall…), that your PV system generated? And if so, is there a way to priorise storage in the battery vs EV-PV excess charging or pv-excess-charging over storage? Do you have opted for a 22kW onbord charger for your taycan? I wonder whether the 22kW OBC will support plug&charge for AC charging and will work with HEM.
Kind regards
Burkhard

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