Preheating with power from grid

ben1

Well-Known Member
First Name
Ben
Joined
Jul 8, 2022
Threads
5
Messages
222
Reaction score
274
Location
belgium
Vehicles
tesla,porsche
Country flag
Typically my Taycan is connected to the grid during the night.
I have it programmed to charge the car to 80% by 6AM. I did not program preheating. I don't want to preheat everyday.
The charging works fine.

Some days, around 8AM, I want to preheat the car. I take the app, select preheat. The car starts to preheat.

But, it looks like it does this using current from the battery. Not from the grid. While it is still plugged in to the grid.
This is stupid. If it is connected to the charger, it should take electricity from the grid, not start depleting the battery.


Do you also have this behaviour ? Is there a way to fix this ?

My Tesla will always use power from the grid to preheat (if it is connected to the grid of course).
Sponsored

 
  • Like
Reactions: DRR

W1NGE

Well-Known Member
First Name
Adrian
Joined
Jan 11, 2021
Threads
31
Messages
8,733
Reaction score
5,213
Location
Aberdeen, Scotland
Vehicles
GTS ST, Macan T
Country flag
Typically my Taycan is connected to the grid during the night.
I have it programmed to charge the car to 80% by 6AM. I did not program preheating. I don't want to preheat everyday.
The charging works fine.

Some days, around 8AM, I want to preheat the car. I take the app, select preheat. The car starts to preheat.

But, it looks like it does this using current from the battery. Not from the grid. While it is still plugged in to the grid.
This is stupid. If it is connected to the charger, it should take electricity from the grid, not start depleting the battery.


Do you also have this behaviour ? Is there a way to fix this ?

My Tesla will always use power from the grid to preheat (if it is connected to the grid of course).
I believe the Taycan will trickle charge when connected and pre-heat / cool is active post your charging window. This may show as power being drawn from the car but in all probability the grid and car battery are in tandem.

None of this is user configurable.
 

satchurator

Well-Known Member
Joined
Mar 22, 2021
Threads
42
Messages
634
Reaction score
600
Location
Massachussets, USA
Vehicles
MY22 CT4
Country flag
I happened to notice this last weekend. In my case I have a general profile target (I don’t have timers to hit a target by 6am like you). With the car at its charge target, manual preheat does seem to draw from the HV battery. In my case, my general profile kicked in and with some lag, charging brought the SOC back to target quickly after preheat (quickly partly thanks to my 80A PWCC but let’s not go there).

There might be some incantation of profiles and timers that would allow you to target your 80% by 6am but then automatically top up to maintain 80% under later preheating. Bat signal to @Jhenson29 for that question.
 
Last edited:

02bluesuperroo

Well-Known Member
First Name
Rob
Joined
Aug 25, 2021
Threads
11
Messages
439
Reaction score
240
Location
SE FL
Vehicles
2022 Porsche Taycan 4s
Country flag
The only pre-heat I see is for the climate control. How do you pre-heat the battery from the app?
 

satchurator

Well-Known Member
Joined
Mar 22, 2021
Threads
42
Messages
634
Reaction score
600
Location
Massachussets, USA
Vehicles
MY22 CT4
Country flag
The only pre-heat I see is for the climate control. How do you pre-heat the battery from the app?
The OP is talking about climate-control preconditioning of the car cabin, not HV battery preconditioning. It's unfortunate and confusing that the same phrase is used to describe priming the HV battery temperature ahead of fast DC charging. Currently, the only way to do that is indirect, through PCM navigation to a charging destination.
 
  • Like
Reactions: DRR


W1NGE

Well-Known Member
First Name
Adrian
Joined
Jan 11, 2021
Threads
31
Messages
8,733
Reaction score
5,213
Location
Aberdeen, Scotland
Vehicles
GTS ST, Macan T
Country flag
I happened to notice this last weekend. In my case I have a general profile target (I don’t have timers to hit a target by 6am like you). With the car at its charge target, manual preheat does seem to draw from the HV battery. In my case, my general profile kicked in and with some lag, charging brought the SOC back to target quickly after preheat (quickly partly thanks to my 80A PWCC but let’s not go there).

There might be some incantation of profiles and timers that would allow you to target your 80% by 6am but then automatically top up to maintain 80% under later preheating. Bat signal to @Jhenson29 for that question.
There is no incantation.
 
OP
OP

ben1

Well-Known Member
First Name
Ben
Joined
Jul 8, 2022
Threads
5
Messages
222
Reaction score
274
Location
belgium
Vehicles
tesla,porsche
Country flag
The OP is talking about climate-control preconditioning of the car cabin, not HV battery preconditioning. It's unfortunate and confusing that the same phrase is used to describe priming the HV battery temperature ahead of fast DC charging. Currently, the only way to do that is indirect, through PCM navigation to a charging destination.
Yes indeed, I am referring to climate-control preconditioning of the car cabin.
This is especially interesting for a road trip. To pre-heat the cabin to use the battery less for cabin heating while driving, to have more range.
But it is all pointless if the pre-heating is done with the battery.

With my Tesla it is very clear that it tries to maximize grid power use.
 

Fish Fingers

Well-Known Member
First Name
Ian
Joined
Feb 20, 2021
Threads
49
Messages
1,847
Reaction score
2,370
Location
Cheshire
Vehicles
Taycan RWD
Country flag
My car is set to charge to 85% at 04.30am (end of cheap rate).

In winter if its iced up and I am due to leave in say 30-60 mins, I use the app to both pre-heat the car, but also switch Direct Charge on at the same time.
Then just toggle both off when I get in the car.
 


W1NGE

Well-Known Member
First Name
Adrian
Joined
Jan 11, 2021
Threads
31
Messages
8,733
Reaction score
5,213
Location
Aberdeen, Scotland
Vehicles
GTS ST, Macan T
Country flag
Yes indeed, I am referring to climate-control preconditioning of the car cabin.
This is especially interesting for a road trip. To pre-heat the cabin to use the battery less for cabin heating while driving, to have more range.
But it is all pointless if the pre-heating is done with the battery.

With my Tesla it is very clear that it tries to maximize grid power use.
The logic here is different in that cabin preheat or precool is intended to be targeted for a given departure time as part of a charging session.

When off grid then on-demand preheating or precooling is also possible.

The only way around this if you are 100% certain that the battery is being used even when connected to your EVSE after a completed charging session is to use direct charge which will draw from the grid to charge and charge + cool / heat. A bit of a cheat and not quite the answer either

I thought there was another thread some months back that a forum member had concluded that if left connected to the grid and no charging session was active and precool / heat was active that the energy for this came from the grid.

Does the charge port indicator flash blue or green when connected and preheat/ cool active? If green then that suggests a draw from the grid.
 
OP
OP

ben1

Well-Known Member
First Name
Ben
Joined
Jul 8, 2022
Threads
5
Messages
222
Reaction score
274
Location
belgium
Vehicles
tesla,porsche
Country flag
Does the charge port indicator flash blue or green when connected and preheat/ cool active? If green then that suggests a draw from the grid.
I have a power meter connected to the EVSE. So I can see when current is flowing from the grid.

I'll try the solution with also enabling direct charge. But it is a pity porsche did not think about this. It is a fundamental feature of an EV in my opinion to be able to leave with maximum battery and a heated cabin for maximum range.
 

Scandinavian

Well-Known Member
First Name
Peter
Joined
Nov 3, 2019
Threads
47
Messages
3,049
Reaction score
2,640
Location
France
Vehicles
Taycan T, Tesla M3P, Aston Martin DB9, Porsche 996 C4 Cab
Country flag
I have a power meter connected to the EVSE. So I can see when current is flowing from the grid.

I'll try the solution with also enabling direct charge. But it is a pity porsche did not think about this. It is a fundamental feature of an EV in my opinion to be able to leave with maximum battery and a heated cabin for maximum range.
If it really is cold out, it is even more important to get some heat into the battery. When you start driving in the morning the Taycan will start to heat the battery to get as close to optimal conditions for it as possible ( about 30 C).

Try to set a departure time and finish both charging and preheating at your time to depart and check the battery temperature.
 

W1NGE

Well-Known Member
First Name
Adrian
Joined
Jan 11, 2021
Threads
31
Messages
8,733
Reaction score
5,213
Location
Aberdeen, Scotland
Vehicles
GTS ST, Macan T
Country flag
I have a power meter connected to the EVSE. So I can see when current is flowing from the grid.

I'll try the solution with also enabling direct charge. But it is a pity porsche did not think about this. It is a fundamental feature of an EV in my opinion to be able to leave with maximum battery and a heated cabin for maximum range.
I guess but if you are fussy about time of day charging for lower rates then this further complicates the logic and what is practical to achieve.
 

madeyong

Well-Known Member
First Name
Mike
Joined
Sep 28, 2021
Threads
21
Messages
302
Reaction score
274
Location
New Jersey
Vehicles
Taycan Turbo S; BMW X7
Country flag
My car is set to charge to 85% at 04.30am (end of cheap rate).

In winter if its iced up and I am due to leave in say 30-60 mins, I use the app to both pre-heat the car, but also switch Direct Charge on at the same time.
Then just toggle both off when I get in the car.
I do this too but I don’t think you need to toggle off the pre-heating. It shuts off and defaults to my normal climate setting as soon as I put the car in drive. I do need to toggle off Direct Charge and have at times forgot and did later on the app.
 

02bluesuperroo

Well-Known Member
First Name
Rob
Joined
Aug 25, 2021
Threads
11
Messages
439
Reaction score
240
Location
SE FL
Vehicles
2022 Porsche Taycan 4s
Country flag
The OP is talking about climate-control preconditioning of the car cabin, not HV battery preconditioning. It's unfortunate and confusing that the same phrase is used to describe priming the HV battery temperature ahead of fast DC charging. Currently, the only way to do that is indirect, through PCM navigation to a charging destination.
It seems to me there should be another type of pre-heating that nobody discusses, and maybe it's for good reason, but what about heating up the battery before you begin your drives so that the battery isn't so inefficient?

Climate control pre-heat
Charging pre-heat
Driving pre-heat
 
  • Like
Reactions: DRR

W1NGE

Well-Known Member
First Name
Adrian
Joined
Jan 11, 2021
Threads
31
Messages
8,733
Reaction score
5,213
Location
Aberdeen, Scotland
Vehicles
GTS ST, Macan T
Country flag
It seems to me there should be another type of pre-heating that nobody discusses, and maybe it's for good reason, but what about heating up the battery before you begin your drives so that the battery isn't so inefficient?

Climate control pre-heat
Charging pre-heat
Driving pre-heat
Covered by charging and preheat of cabin assuming you plan your departure for the same time.

Only alternative is to add a DC charging location as either a destination or stopover to precondition (not preheat exclusively) the battery.
Sponsored

 
 




Top