Baffled by preconditioning

[MrBadger]

I would just get in, set destination and drive. If you think range is marginal and you need to be there for a particular time, add a bit (~30 minutes?) on to your journey in case you need to stop. If you don't need to stop, its a bonus.

Yea, I'll top up to 90 something before a big drive, but that's only keeps more options open for when on the road - for similar reason, I don't commit too early for a supercharger stop - pre conditioning saps too much range for negligible time saving at a supercharger and if you have already been on your way for some time, things are not going to be totally cold, so a final 10 miles pre conditioning is likely to be sufficient - a bit more like how it use to work until they changed things.

 

[GeorgeSymonds]

I’d simply charge to 100% overnight, then 15mins before leaving the house remotely turn on the climate from the app. If the battery is too cold, it will also turn on the battery heater. As far as I can tell preconditioning is just an automatic timing of this.

You can try and get fancy by controlling the charging to finish just before you’re due to leave, but this is a risky if it gets it wrong leaving you with less than 100% charge, and the heat from charging doesn't make a lot of difference on a home charger.

 

[Mullermn]

Thanks for the detailed response. I’ll charge to 100% tonight for be ready for 06:30 in the morning. So to precondition do I just go onto the Tesla app, schedule, precondition, set departure time to 06:45 and click precondition to on?

The other thing you may not realise if you've not had a Tesla long is that in reality stopping to charge is really, really low hassle and you'll probably only be there for a matter of a few minutes because superchargers put power in to the battery incredibly quickly compared to home charging. You don't have to weave in/out of a pump space (charging bays are just like normal parking spaces) and you don't even have to do anything to pay, assuming you've set up payment in the app. The largest inconvenience is walking round to the rear of your own car twice to plug/unplug.

Basically I wouldn't worry about it.

 

[WannabeOwner]

in reality stopping to charge is really, really low hassle

but not always.

its 5 minutes to get off the highway ... and back on again.

You might have a slow-charger (and through inexperience not realise / not move to a different stall)

All stalls might be full and you have to queue. For me this is the biggest "no". I aim to make all my out-and-back type journeys so that I only charge on the return journey. That way I'm not late for a meeting because I had to wait for a supercharger, and on my way home I don't mind a delay because its on my time, and I can do Emails / whatever whilst I'm waiting.

I don't subscribe to the thinking that for a journey where range is tight one wouldn't charge to 100%. I have plenty of experiences of journeys where, on paper, I wouldn't reach the destination but in practice traffic / roadworks meant that I spent 30 minutes driving at 50 / whatever, and that gave me enough extra range to get there. But if I had only charged to 90% that would have been around 30 miles less range that I had.

Foul weather too. The only time I have very very nearly run out was a lovely summer's day when thunderstorms meant I was driving in torrential rain. I hadn't bothered to charge to 100% because "This journey is easy for range". Since then I have charged to 100% if my journey is over 70% of my max range. Just contingency.

Equally if I will definitely have to Supercharge that extra 10% / 30 miles may enable me to reach a more distant Supercharger - even more so if I hit traffic / roadworks, and is 30 miles I haven't got to Supercharge / pay for

All that said, "out of range" is a long drive, and stopping is going to be for the benefit of the driver's wear-and-tear anyway But personally I want that to be on the return-leg, not the outbound one, so I'm not delayed

 

[qwickshot]

Agreed, there is no reason not to charge to 100% if you are going anywhere near the maximum range of the car. Just charge it and don’t worry about it.

You’ll not suddenly degrade the battery by charging it to 100%. The degradation accelerates when you charge it to 100% and then store it for long periods of time (E.g. many months).

A few hours before you get in the car in the morning is not what anyone would consider long periods of time. It’s also good to charge it up to full occasionally for the BMS to calibrate.

 

[Adopado]

I’d simply charge to 100% overnight, then 15mins before leaving the house remotely turn on the climate from the app. If the battery is too cold, it will also turn on the battery heater. As far as I can tell preconditioning is just an automatic timing of this.

I will just chip in that Supercharger preconditioning is not quite the same as warming your battery before departure from home ... it's just that Supercharger optimum charging temperature is a good bit higher than what takes place with a 15 minute warm up before leaving. This is evident from the fact that you can have been travelling down the motorway for couple of hours yet preconditioning will kick in to raise the battery temperature higher.

I've sometimes intentionally avoided preconditioning by not having the navigation to the Supercharger active ... and then at the start of the charging session a message comes on screen to indicate that there is prewarming/conditioning going on to facilitate Supercharging... which I'm then paying for at a higher rate than my home charging of course.

 

[Mullermn]

Basically I wouldn't worry about it.

Just to be clear - when I said I wouldn't worry about it, I didn't mean don't charge to 100% - I would do that. I just mean I'd get on with the journey and not worry about babying the car to eek the absolute max out of the range. It's not worth the hassle when charging is so easy, IMO, and you're just giving yourself an unnecessary thing to fret about.

 

[waltonmark]

To be fair would do me good to use a supercharger and learn the ease of the process. What’s the etiquette re waiting for a free charger to become available? Looking at the map it’ll be keele services southbound I’ll use on the way home. Only 4 chargers there so every chance all 4 could be in use when I arrive…

 

[starharbour]

Thanks for the detailed response. I’ll charge to 100% tonight for be ready for 06:30 in the morning. So to precondition do I just go onto the Tesla app, schedule, precondition, set departure time to 06:45 and click precondition to on?

yep that's it. depending on the temp outside and the temp of the battery, the car will auto-precondition to be ready for your departure time.

As stated above, I tend to avoid pre-conditioning on mains as it will eat up at least 3-4 KWH on "peak" energy rate. I find often that it just simply isn't worth the cost to do versus the benefit of having a bit more regen, but i've changed my mind on this topic a couple times already so just see what works for you.

 

[Mullermn]

To be fair would do me good to use a supercharger and learn the ease of the process. What’s the etiquette re waiting for a free charger to become available? Looking at the map it’ll be keele services southbound I’ll use on the way home. Only 4 chargers there so every chance all 4 could be in use when I arrive…

i have had to use one so rarely in the 4,600 miles I have had mine that I haven’t got many tips other than that if there are ‘a’ and ‘b’ chargers (eg bays 3a, 3b, 4a, 4b etc rather than 1,2,3,4) then the a and b are a pair that share the same power supply, so only take the second bay if there aren’t any others available as you and your partner will charge at half the rate.

Tesla only request payment after charging so if you’ve not set it up in advance don’t worry, you’ll be able to charge once and then sort it out in the phone app later.

 

[WannabeOwner]

every chance all 4 could be in use when I arrive…

SatNav will show you occupancy / free stalls as you approach - if you have a choice of an alternate you could take that decision

But if all stalls are full and queuing is necessary a lot depends on the site - none of them were designed for queuing for EV chargers ...

I agree its worth having a go when not critical. My suggestions would be:

Worth sitting in the car for a minute or two and checking that it ramps up to "expected" kWs. That used to be something that was easy to know, but now there are "old" stalls and also "new" ones. I suppose a simple rule of thumb is that if the stall has two cables (one that will fit M3/MY and the other for legacy MS/MX) its an old one. A bit over 100 kWs is the limit. For that "old" type the stalls are in pairs (marked A and B - so 1A, 1B ... 2A, 2B ...) and they share power. So you should park every-other-stall to avoid sharing (the A/B are not always adjacent stalls, particularly when they go round a corner, so best to check that ...). Pairing/sharing is all the more important on these, old, stalls as they are lower power anyway.

On a new stall (one cable) you could get 200kW - maybe 250kW for brief periods. To get full power your car needs to be "low" state-of-charge - around 0%. As it fills up the kW will drop. Might be worth monitoring it (the first time) and making a note of kW at 10%, 20%, ... so you know what to expect. Also depends on the temperature of your battery and so on ...

Some sites (e.g. M4 hotel near Heathrow) have a mix of 2-cable old chargers and 1-cable new ones - definitely want to park at a new charger stall there

But basically the car should charge "fast" from 10% to, say, 60-70%, quite a bit slower up to 80%, quite a lot slower to 90%, and then VERY slow to 100%. So if you can (i.e. you can get to next charger OK) charging to 70% is probably about ideal. But (unlike brim-filling the tank in an ICE) you only need enough to get to your destination / next charger - and if that is home presumably you have cheaper fuel there than the Supercharger price.

If you get much less kW than you expect (make sure you are not sharing an old stall) then move to another stall. On fairly rare occasions a stall may be running slow ... hence my suggestion to stay in car for a minute and check it ramps up. Annoying to head to the facilities, come back 15 minutes later and find you've only gained a dribble

if there aren’t any others available as you and your partner will charge at half the rate.

its not quite like that, the car that started first gets the lions share ... but as they fill up to 70% their kW drops anyway, and then the 2nd car gets more ... and becomes the 1st car once the original car leaves.

 

[Adopado]

To be fair would do me good to use a supercharger and learn the ease of the process. What’s the etiquette re waiting for a free charger to become available? Looking at the map it’ll be keele services southbound I’ll use on the way home. Only 4 chargers there so every chance all 4 could be in use when I arrive…

Keele isn't a shining example of fast Supercharging unfortunately. Only 150kW max rather than the newer V3 Superchargers. They also suffer from power sharing (and with only 4 stalls you guarantee you're going to be sharing i.e. 2 stalls share the same power supply) so don't measure your charging speed potential based on experiences there! Keele may well be your best option but I have used Trentham to avoid Keele ... bad news is it's off the motorway and the roads around about are busy at certain times ... but the Superchargers there are fast V3 and there's more of them. It's probably a toss up.

 

[GeorgeSymonds]

Keele isn't a shining example of fast Supercharging unfortunately. Only 150kW max rather than the newer V3 Superchargers. They also suffer from power sharing (and with only 4 stalls you guarantee you're going to be sharing i.e. 2 stalls share the same power supply) so don't measure your charging speed potential based on experiences there! Keele may well be your best option but I have used Trentham to avoid Keele ... bad news is it's off the motorway and the roads around about are busy at certain times ... but the Superchargers there are fast V3 and there's more of them. It's probably a toss up.

Keele is rubbish, but if you want a big chsrge (say 10% to 70%): head to Trentham gardens, it’s 5 mins off the motorway but V3 and I’ve reached 250kw there, or if you can last to Hilton park, they’re not too bad.

 

[WannabeOwner]

To get full power your car needs to be "low" state-of-charge - around 0%

Sorry, significant typo ... that should be "around 10%" - 0% would also work, but its a bit hard to consistently achieve that in the real world!!

 

[Midnightsun]

Tuning into a UK thread from Canada. Snow is mostly gone, summer tires are on and we rarely see below 0C at nights any more.

We have a 2020 Model Y with low and high regen adjustment and a 2022 Model S with no adjustment. With the Y on high regen, I cannot see any difference between the 2 so it looks like default on newer cars with no regen option is high.

That being said I am not sure why they did not opt to push the blended braking option in the UK. This option is activated on both cars and I must say it is seamless. The concern was mostly on the real winter roads we have here due to too much regen however over the years this has been tweeked and the car reacts quite normally when releaseing the accelerator in extreme slip conditions to the point that no wheel lock-up is felt. There may be some but it is so little it's hard to detect. Could also be partially due to running 4 dedicated winter tires.

Back to the blended braking, I can leave at -20C or +30 C and the car behaves the same when it comes to one pedal driving without any preconditioning which also eliminates the warning about reduced regen that would come up on the screen.

I really found it annoying that the car would behave differently with reduced regen on cold morning or if charged to 100% which now has been completely resolved with blended braking.

Motion sickness has been mentioned however this is just because you have not mastered one pedal driving completely yet. You do not simply let go of the accelerator, you start feathering it off slowly to slowly come to a stop and therefor can apply as much or as little regen as you like. Did not take me much time to adjust however my wife took a little longer but eventually mastered it perfectly.

Hope you get this option in the UK soon!