Pre heating question

[wenkatn]

Question regarding Pre heating the cabin and the battery before a long drive on a 0 degree weather in UK.

I have MG4 Trophy long range. Scheduled charging during off peak hours between 11:30 pm and 5:30 am. So it gets to 100% by 5:30 am. I have ohme epod EVSE and with octopus intelligent go tariff.

Planning to start a 200 mile round trip by 8 am when it would be below or at 0 degree Celsius.
I have never tried pre heating the cabin, seat, steering wheel or the traction battery. I’d like some advice please.

Although the cable will remain connected to the car, the charging will be stopped by 5:30 am when it reaches 100%.

If I schedule a pre heating of the cabin, seat etc to start at 7:45 am just 15 minutes before i start the journey, will it use the battery or the mains?

Would it be beneficial to pre heat the battery as well? If so, for how long before the journey.

Thanks

 

[Ian Key]

The pre-heat of the cabin might not work if the car is plugged in but not charging so you might have to nip out and disconnect the charger.
I'd just preheat the cabin 10 minutes before you go as the heater will only stay on for 10 minutes, you can't schedule it though.
Pre-heating the battery will have no advantage unless it gets a lot colder as the amount of battery used will be greater than the range advantage and the battery heats up as its used.

 

[wenkatn]

The pre-heat of the cabin might not work if the car is plugged in but not charging so you might have to nip out and disconnect the charger.
I'd just preheat the cabin 10 minutes before you go as the heater will only stay on for 10 minutes, you can't schedule it though.
Pre-heating the battery will have no advantage unless it gets a lot colder as the amount of battery used will be greater than the range advantage and the battery heats up as its used.

Thanks for the insight. I wonder how much battery percentage drops for that 10 minutes cabin heating before the journey. It would be ideal if i start with a 100% SOC.

 

[Ian Key]

To save yourself range anxiety why not plan a quick coffee and charge stop. You could keep the heater on all the time and enjoy the drive without going eco.

 

[wenkatn]

To save yourself range anxiety why not plan a quick coffee and charge stop. You could keep the heater on all the time and enjoy the drive without going eco.

Thanks. This is more of a range testing trip actually for me which my family doesn’t know. 180 miles round trip. I’m on trophy LR and interested to know if i could do the full trip without needing to public charge at sub zero icy weather.
By half way I’d know whether it needs to be topped up in which case happy to stop for a coffee break.

 

[mg4mc]

It may depend on your charger. If you are on IO Go then your charging could end any time up to your set end time (mine finished charging at 20:15 last night, it started around 16:00 when I plugged in).

The car was going to be used at 07:30 this morning, so I set the charger to start preconditioning at 07:00, and set the car to schedule battery warming at the same time. At 07:15 I manually switched on the cabin pre-heat via the app. Frosty morning here at -3°C.

The battery warming and AC then ran off the mains (as the charger was switched on by the pre-condition setting) leaving the car at 100% for my wife to start her journey.

 

[JonnyG]

When I do on a long journey in the cold (<5c) I do something like this to start fully charged and warm (seems similar to above post but I have an old dumb home charger !)

1. Turn on Intelligent Battery Heating in the car
2 Set the charge to 90% overnight.
3. An hour before settiing off I restart and set the charge to 100%
4. Keep an eye on the SOC %
5. 20 minutes before setting off and while still charging I preheat the cabin and try to turn on the battery pre heat too from the app (going into the schedule tab from Charging managament area). Sometimes it won't turn on but recently it has in this colder weather.
6. Try and synchronise the end of charging to 100% SOC with the end of all preheats.
7. Set off in ECO mode, Energy Saving mode ON, HVAC set to ECO mode and minimise the use of AC in the HVAC , just use the fan and heater as required.

 

[2Sheds]

We have an Ohme Home Pro charger which has a preconditioning feature which you can schedule via the app to come on for a set time before you want to use the car to allow for preheating of the cabin/battery using the mains supply rather than the battery. (You'll still have to request the preheat via the MG iSmart app, obviously). I think your Ohme epod should have the same precondition feature? As far as I can tell, it's the same unit but untethered and without the screen?

What I'm not sure about is how this will interact with your tariff. We are on OVO Charge Anytime, which does not have have set charging windows as such and will keep power on until the set %age has been added, or the charge is paused via the app. So as the charger doesn't know the SoC of the car, when the charge reaches the set limit (usually 80%, but whatever it's set to) and still has not reached the requested additional charge, it will just keep power applied. This means that the cabin preheating can be done without the preconditioning option. It also has the nice side effect the the preheat will be done at the cheap car charging rate! I think otherwise the preconditioning option uses normal daytime rate.

So to summarise, I think you should be able to do a cabin/battery preheat from the mains using the Ohme app, but it will probably be at your normal daytime electricity price.

 

[Rolfe]

Thanks for the insight. I wonder how much battery percentage drops for that 10 minutes cabin heating before the journey. It would be ideal if i start with a 100% SOC.

In my SE SR it drops by 2% so it's not negligible. That's just cabin heating, not battery. There is a software fix that allows the car to do it while plugged in though, and presumably using mains electricity.

 

[wenkatn]

In my SE SR it drops by 2% so it's not negligible. That's just cabin heating, not battery. There is a software fix that allows the car to do it while plugged in though, and presumably using mains electricity.

Yesterday when i tested this, i was able to pre heat the cabin while the charging cable was connected. It didn’t use the mains. By the time i started the pre heating the battery was already fully charged. The pre heating was successful which took 1% of the battery charge. But that 10 minutes wasn’t enough. It looked like it needed another 10 minutes. I had the temperature at 22C. May be i should have had it bit more higher.

It may depend on your charger. If you are on IO Go then your charging could end any time up to your set end time (mine finished charging at 20:15 last night, it started around 16:00 when I plugged in).

The car was going to be used at 07:30 this morning, so I set the charger to start preconditioning at 07:00, and set the car to schedule battery warming at the same time. At 07:15 I manually switched on the cabin pre-heat via the app. Frosty morning here at -3°C.

The battery warming and AC then ran off the mains (as the charger was switched on by the pre-condition setting) leaving the car at 100% for my wife to start her journey.

Thank you.

 

[SimonS]

Yesterday when i tested this, i was able to pre heat the cabin while the charging cable was connected. It didn’t use the mains. By the time i started the pre heating the battery was already fully charged. The pre heating was successful which took 1% of the battery charge. But that 10 minutes wasn’t enough. It looked like it needed another 10 minutes. I had the temperature at 22C. May be i should have had it bit more higher.

Remember that 22c is actually around 17c in real life. I usually set 24c

 

[2Sheds]

Yesterday when i tested this, i was able to pre heat the cabin while the charging cable was connected. It didn’t use the mains. By the time i started the pre heating the battery was already fully charged. The pre heating was successful which took 1% of the battery charge. But that 10 minutes wasn’t enough. It looked like it needed another 10 minutes. I had the temperature at 22C. May be i should have had it bit more higher.

Did you try using the preconditioning function in the Ohme app? If your charger supports it, that should enable you to preheat from the mains.

 

[wenkatn]

Remember that 22c is actually around 17c in real life. I usually set 24c

I know people have been advocating to remember the 5 degree or so offset to achieve the desired temperature. But since i got it in Oct this year it was perfect in term of the temperature. I set it to 21 and it feels like 21. May be the recent versions have this thing rectified.

 

[PaulD]

The pre-heat of the cabin might not work if the car is plugged in but not charging so you might have to nip out and disconnect the charger.
I'd just preheat the cabin 10 minutes before you go as the heater will only stay on for 10 minutes, you can't schedule it though.
Pre-heating the battery will have no advantage unless it gets a lot colder as the amount of battery used will be greater than the range advantage and the battery heats up as its used.

Just reading through this thread and noticed your comment about not being able to schedule cabin pre-heating.

That's really disappointing, considering it's a feature that's really easy to implement and is also one big advantage of EVs.

I'm sure when it arrives I'll prefer my Xpower to my Puegeot e2008 in many ways, but the Peugeot lets you set up as many schedules as you want with different days and times. When you set up the schedule you effectively tell it what time you'll be getting in the car. It then starts heating up far enough in advance to achieve the temperature by that time, and then maintains it for a further 10 minutes past that time. I'm going to miss that.

 

[tsedge]

I can see how that would work well for people with a set routine, such as a daily commute, with predictable times. I would keep missing the window and the car would be cool again before I got in!

 

[Emgie 4]

In my SE SR it drops by 2% so it's not negligible. That's just cabin heating, not battery. There is a software fix that allows the car to do it while plugged in though, and presumably using mains electricity.

A software fix for the car may allow ability to preheat when plugged in and not charging, but not from mains power, remember if your wall box supply/mains is off via your tariff/schedule the car will not have the ability to override this.
The car can't get power from a cable when none available (only workaround being the preheat tariff option such as Ohme have as @2Sheds mentions)

My analogy of this, consider a normal room convector heat that has its own thermostat and timeswitch, the heating element will come on and off as stat or timer calls for heating BUT if I switch of the plug at the wall the heating stops regardless of what the heater/stat is asking for.

Only difference with car charger is the car does (smartly?) recognise it is plugged in.

 

[siteguru]

But not everyone is on a time-of-day tariff.

 

[Emgie 4]

But not everyone is on a time-of-day tariff.

Agreed, but it's with TOD tariffs people have the preheating issue.

Of the three scenarios; unplugged, plugged in and charging (or ability to charge) and plugged in not charging or available (TOD tarriff)
It is only when plugged in without power available causes the problem - the car can recognise its connected but also sees no power available so won't allow preheating, until it's either unplugged or powered on.

Don't know whether this was by design to save battery power, or a mistake by MG, but rumour has it an update does/will rectify in the future.

 

[siteguru]

Agreed, but it's with TOD tariffs people have the preheating issue.

Not necessarily ... until I had the recent updates applied to my car then I couldn't ever preheat whilst plugged in and not charging. The charge point was in the Waiting state waiting for the car to request a charge, and the car wouldn't accept the remote HVAC or battery heating controls from the app. Now it all works as expected ... nothing to do with being on a TOD tariff or not. (I'm not)

 

[Emgie 4]

Not necessarily ... until I had the recent updates applied to my car then I couldn't ever preheat whilst plugged in and not charging. The charge point was in the Waiting state waiting for the car to request a charge, and the car wouldn't accept the remote HVAC or battery heating controls from the app. Now it all works as expected ... nothing to do with being on a TOD tariff or not. (I'm not)

Fair enough, I hadn't experienced that problem myself, and understood from other posters that TOD tarriffs did relate to their issues.

Although perhaps my car already had update (July '23 Trophy) and I suspect different people are have different problems.

My main point, 'you can't get blood out of stone' If power from wall box is off due to TOD tarriff, the car has no control over your house supply and can't use mains to preheat.