Tesla to fix smart charging (wake vehicle from sleep via Zappi charge)

[CMc1]

For those that aren’t aware, when using EV chargers such as the Zappi, often the car won’t wake up from sleep if the solar generation is sufficient.

Apparently the car isn’t compliant with IEC 61851-1 for smart charging.

 

[kevuwk]

Took them long enough to acknowledge it, Myenergi have probably been in contact with them for around 3 months

 

[Epico]

Well at least that have some time to fix it...as generation at this time of year is almost non existent...looking forward to completely free and 100% renewable energy from around march...here's hoping!

 

[jimbo_hippo]

I'm hoping that at some point, Tesla will look at how their Wallcharger talks to the Powerwall 2. It seem a bit daft that the Powerwall setup is pretty 'smart' already and can make decisions about your house but the Tesla charger, whilst perfectly fine, reliable and sexy, is totally out of your decision making equation. Even if the charger stayed 'dumb' it would be good for the Powerwall Gateway to be able to make on or off decisions based on the same kind of criteria it makes with other loads etc. I seem to remember being told that myTesla Wall Connector is powered from the Gateway. Whilst that doesn't mean it's any smarter, it's at least 'geographically' feasible rather than just tapped into the Consumer Box.

 

[AndrewGR]

I installed a Zappi smart charge point to take advantage of my solar panels which were, prior to getting the car, exporting about 80% of generation to the grid. I've had the Model 3 since mid December. On the few occasions that the sun has been shining enough for me to have significant surplus power, I have determined that not only does the car not wake up to charge, the Zappi usually reports a fault and needs to be reset. So I've given up with the 'eco modes' awaiting the software update to sort the problem. Meanwhile, on days when I have anticipated a bit of surplus energy, I've set the car to charge at a low rate - say 6-10 amps, so that it will absorb any surplus energy over the day. However, I've noted from TeslaFi that the charging efficiency is much lower at low currents than when I charge at the full 32 amps. Typically varying from about 80% at 6 amps to 93% at 32 amps. I'm guessing this is because there is a fixed loss overhead when charging regardless of the charge current - but it may simply be that the charging system is designed to work at 32 amps and is much less efficient at low currents. Does anyone know the reason?

The Zappi offers the opportunity to 'top-up' available solar power to a desired minimum level from the grid. The minimum charging rate that any EV will accept is 1.4kW. However, if charging at such a low level (6 amps) is going to make inefficient use of the top up grid power, it does raise the question of whether using surplus solar is worth it unless there is sufficient to supply most of the minimum charge rate. Especially if the car can otherwise be charged using cheap off-peak electricity from Octopus Go.

Any thoughts?

 

[mpandrew]

I don't know the reason but do know that charging at such low rates (32A is low) is pretty efficient, the battery will accept the energy with marginal losses. What may be the reason for worse efficiency at 6A is that a larger proportion of that energy is powering the car computers, sensors, battery heating and charging circuits. Thereby while the battery itself will be charging efficiently a large percentage of input power is just ancillary equipment load. Clearly as the rate increases a larger proportion of the energy is useful charging power so efficiency is better. I don't use TeslaFi, wonder if it calculates efficiency itself or uses a car provided metric? There will come a point where 'wasted' energy as a proportion will start increasing again as the car works harder to cool the battery and the cells themselves lose charging efficiency by self heating. No doubt the car is well aware of this and tries to trade-off speed of charge vs battery self heating by reducing the charge rate.

It's interesting but probably not worth worrying about, as long as you have a surplus of sunshine electrons then charge at whatever rate you can maintain without dipping into the grid.

 

[CMc1]

A user on the myenergi forums is reporting that 2020.8.1 does not fix car wake/charge issue.

Tesla Model 3 - won't wake up via charger

 

[Obliter8]

I'm hoping that at some point, Tesla will look at how their Wallcharger talks to the Powerwall 2. It seem a bit daft that the Powerwall setup is pretty 'smart' already and can make decisions about your house but the Tesla charger, whilst perfectly fine, reliable and sexy, is totally out of your decision making equation. Even if the charger stayed 'dumb' it would be good for the Powerwall Gateway to be able to make on or off decisions based on the same kind of criteria it makes with other loads etc. I seem to remember being told that myTesla Wall Connector is powered from the Gateway. Whilst that doesn't mean it's any smarter, it's at least 'geographically' feasible rather than just tapped into the Consumer Box.

I have said this very thing to the power wall sales guy. He agrees and assures me he has fed it back to the mothership. More people saying the same thing to Tesla can't hurt...

 

[ACarneiro]

It may well be that the v2 Wall Connector will be able to do just that.

 

[tsh2]

I don't know the reason but do know that charging at such low rates (32A is low) is pretty efficient, the battery will accept the energy with marginal losses. What may be the reason for worse efficiency at 6A is that a larger proportion of that energy is powering the car computers, sensors, battery heating and charging circuits.

I have noticed that if I charge overnight, the first half hour provides only 0.5 mi/hr range, most of 2kW looking like it is going to heating (outside temp 1.5C). I think I've also seen charges where the car switches back to this mode as the pack cools down again.

 

[jimbo_hippo]

It may well be that the v2 Wall Connector will be able to do just that.

Acarneiro and Obliter8, there was a short piece in the Now You Know YouTube channel where some currently passive code is in the new version ready for the functionality we're all hoping for. I've also been told by my supplier that Tesla are quoting Q3 2020 for supply of new Wall Connector in our territory. I'm going to carry on sharing the current one between the LEAF and the Model 3 and add a second Tesla one as soon as available.

 

[AndrewGR]

Zappi Update:
Zappi now working fine in Eco+ mode for me after a firmware update recommended by MyEnergi. My M3 has been happily charging on and off as the sun comes and goes all day today. I've only managed to add about 20 miles but that was all 'free' energy off the roof which would otherwise have been exported to the grid. I expect to get more 'free' charging as the summer draws nearer! The Tesla app sends a message every time charging stops because there is less than 1.4kW available which is a bit irritating. I don't think the latest Tesla update has made a difference to this. However, the car probably hasn't not been charging for long enough to go into deep sleep - I'll have to see whether it wakes and starts charging when the sun comes out tomorrow and if not, what the Zappi does in response.

 

[MrBadger]

The Tesla app sends a message every time charging stops because there is less than 1.4kW available which is a bit irritating.

That should be configurable in the app - certainly is for regular charging - cog/notifications/charging started+interrupted+complete

 

[Adopado]

Zappi Update:
Zappi now working fine in Eco+ mode for me after a firmware update recommended by MyEnergi. My M3 has been happily charging on and off as the sun comes and goes all day today. I've only managed to add about 20 miles but that was all 'free' energy off the roof which would otherwise have been exported to the grid. I expect to get more 'free' charging as the summer draws nearer! The Tesla app sends a message every time charging stops because there is less than 1.4kW available which is a bit irritating. I don't think the latest Tesla update has made a difference to this. However, the car probably hasn't not been charging for long enough to go into deep sleep - I'll have to see whether it wakes and starts charging when the sun comes out tomorrow and if not, what the Zappi does in response.

Is that the v2.161 update?

 

[Adopado]

However, the car probably hasn't not been charging for long enough to go into deep sleep - I'll have to see whether it wakes and starts charging when the sun comes out tomorrow and if not, what the Zappi does in response.

Yes, this might yet turn out to be why it's working.

 

[AndrewGR]

Yup. Zappi 2.161

 

[AndrewGR]

VanillaAir
Found the configuration options for notifications - thanks.

 

[hmy7k]

I tried to boost charge on my Zappi this morning whilst car was in a deep sleep and nothing happened.
I think you still need to wake the car for any charging to start.

 

[Adopado]

Yup. Zappi 2.161

I noticed your comment on the Zappi update process ... you may be interested in my (exasperated) post to the Myenergi forum on this topic. It really is a palaver ... as you found out!:
Firmware update process ... OMG!

 

[CMc1]

I’ve had 2.161 for a while and it isn’t fixed. It’s a bug on the vehicle end. Tesla keep saying a fix is inbound, but never turns up. Haven’t confirmed yet with 2020.8.1