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Typical Overnight loss SR+, Cold Weather

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Looking into getting a SR+ in the next six months. I live in Philadelphia with no access to a home charger, however there's a SemaConnect down the street a walkable distance. I'm trying to understand what the lived experience of the smaller battery and no home charger will be like. I know it depends on what charging looks like at destinations I go to. I work from home. I take 20 mile round trips here and there to grab groceries, or longer trips down to the coast. All close enough to superchargers. There's good coverage up and down the mid-Atlantic so I'm not too worried, however, I am concerned about days when I have quick turn-around (come home late, need to leave early) and wouldn't have time to visit the local charger. My nightmare is a cold Christmas Eve returning home with too little battery to get out the door and on the road for Christmas. That's probably it, honestly.

What would folks recommend the minimum charge be when arriving at night, if I needed to leave the next morning unable to charge and the nearest supercharger is 50 miles? What's the typical overnight drain, worst case? That's probably around 20F, if I had to guess. Warm winters lately. Assume I'd run pre-conditioning and heat (again, not plugged in) because, well, I'd drive an ICE before being single.

What would a slow week look like? How long could I leave the car sitting and what battery drain could I expect? Let's say I don't use the car from Sunday to Thursday during the week (hey, we live in the city I can walk to the grocery store and gym).

If I knew I was taking a long trip the next day and charged to ~90%, what would my starting charge likely be the next morning?

How much does all of this management really change with an extra 70 miles?
 
So, in my opinion, I wouldn't own an EV unless I could charge at home in some way. It's way more hassle, and you don't get the often-cited benefit ("Stop for charge? My car is always full every morning!") while lacking the quick fill up capability of a gas vehicle.

We have the LR. We started with only basic 120V charging, and the car went at least 120km every day (75mi). Even with charging 100% of the time it was at home, we'd still need to stop somewhere once a week for some extra charge (one brunch place nearby a charger got extra business from us during this time). Going to the next town over means we'd always need to stop at the Supercharger to make it through the next week. This actually turned 30 minute trips into 70 minute trips (one-way), as we often had to overshoot our destination to get to the charger and then sit for charging.

Story time. We recently were in Montrose, CO without charging at the hotel in cold weather. My wife was at work during the day but didn't take the Tesla. For the few short trips we did (e.g. dinner in the evenings, and only sometimes, sometimes a lunch run) it was an absolute chore to keep that thing charged. Of the 3 or so chargers available, only 1 was convenient for stopping at during other activities. Even then, it was too far from many places and we often had to get the whole group of workers to pick a different place for dinner just so the EV could charge. A couple times I went an hour out of my way to hit a CHAdeMO station so I'd spend less time overall charging (just 3 hours!). Many times though, I just took the dog and sat at the L2 charger watching YouTube videos for hours. This was a good simulation of not having charging at home, and I want nothing to do with it. Too much wasted time and fussing around with where I'm "allowed" to go so there's a convenient charger nearby, not to mention the trips and waiting explicitly for charging.

What you will need to do is build some new habits to make this work:
  • Use public charging habitually. Use it everywhere if stopped for 10 minutes or more. Change where you frequent (groceries etc.) so that it's reasonable near a charger. If you haven't used it yet, I highly recommend PlugShare for finding chargers and checking in.
  • Get used to walking further (since you parked further for charging). This is a benefit of sorts, but don't forget an umbrella!
  • Never get to the point where a station not being available would ruin your day. This is public charging, someone else may be using it. Basically, don't run your charge down very low if it's preventable by charging more frequently (which is less convenient, but missing a critical charge is even more so).
  • Plan for a lot of extra time needed when going places. Getting anywhere where a Supercharger is needed will take more time than you think (and because you don't have at-home charging, this will happen more frequently) due to both the detour and the charge time.
You will need to turn these off, and ensure any new features that cause battery drain are turned off:
  • Sentry Mode (consumes about 14%/day for SR+)
  • Summon Standby (probably consumes the same as Sentry, though if one is on the other doesn't require more power I don't think)
  • Cabin Overheat Protection (if it's parked in the sun or somewhere warm)
  • Don't access the app often. This wakes the car and starts consuming the same 14%/day until it falls asleep (generally within a few minutes, but sometimes it stays awake longer).
You will need to keep in mind...
  • Short hops with heating the cabin are the worst for battery drain. Double the expected usage (i.e. if showing 250mi range, assume it's actually 125mi for your short hop purposes).
  • The LR can charge faster at some L2 stations than the SR+, but stations with this much power available are actually pretty rare (generally they're Tesla wall chargers, not J1772 plugs).
And to address your direct questions...
  • I wouldn't park the car with less than 50% (to give buffer for the next day). Less could be fine, but this wouldn't be negotiable in Winter climates if you need to go 50 miles.
  • Typical drain according to old Stats app numbers is equivalent to about 60W. For a 12h period, that's not quite 1% on the SR+. This probably includes the car waking itself, vampire drain, etc. and isn't the most accurate number. In your case, I'd expect it to be slightly less since it's not plugged in.
  • Drain on a cold night outside is potentially much, much worse. There's contention on here about at what point it will heat the battery, by how much, or if it does at all. Most people in cold conditions don't leave the car unplugged so wouldn't really notice. In my apparently rare experience, you can lose a lot (equivalent to 15% on the SR+). I don't know if that would happen at 20F.
  • Preconditioning the cabin now sometimes preheats the battery as well, which draws a lot more power. I too choose to retain a significant other and will choose heat anyways, but try to delay it until you get in the car if the battery is lower than you'd like. The heat starts blowing in about 30 seconds.
  • Long-term storage various significantly. I've seen anywhere from 1%/day to 1%/week. Leaving it unplugged actually seems to help, anecdotally, so I'd expect closer to the 1%/week mark for you. If it's cold, I'm not sure how this would work though.
  • With the LR, some things actually do change significantly. For one, it adds more range faster at a Supercharger. Having that extra 70mi is also quite significant when you have only a few to play with already. See below. Things like Sentry and the car being randomly awake take the same power from SR+ and LR, but the LR can supply that power for longer.
  • If you charge to 90% the night before, you can expect anywhere between 87-92% in the morning due to various factors.

Effective Daily Range:

This is what I use to tell people the actual daily range.

You will only charge to 90% maximum and keep it above 10% minimum. Thus, only 80% of your capacity is actually used on a day-to-day basis. In terms of "range", that's also 80%.

For a "warm winter", using an extra 30% for the same range is normal in an LR (this would actually be worse in the SR+, as the heat power is the same but with a smaller battery). Add in some other minor losses and you're at 60% of rated range.

That means a 250mi-rated SR+ can be expected to get you around only 150mi within 10-90%.
For a 320mi-rated LR, that's 192mi.

If you wanted to use 20%-80 like many do, that's only 46% of rated. 115mi in the SR+, 147mi in the LR. And keep in mind I didn't factor in that the SR+ should actually be draining more compared to the LR in terms of percent in Winter.

Happy news, it's not Winter all year long!?


tl;dr: It's not impossible but it's highly impractical. You need to love it so much that you're OK with all the extra time and steps needed to keep the car moving. These are my personal observations (plus similar data from other users on here).
 
I wanted to make some other comments specifically on cold weather actually. As if I didn't already type enough!

I'd strongly consider the Model Y over the Model 3. It uses a heat pump instead of a resistive heater, and is significantly more efficient. It also has a couple more auxiliary heaters (radar and wipers IIRC) that will help for it being parked outside.

Ours is garage-kept so I didn't encounter this much, but the Model 3 is a PITA when parked outside in Winter. The wipers get no heat (not from a warm engine nor a heat strip). It takes forever to melt ice off of them if parked outside, and they tend to ice up easily when driving in adverse conditions (you need to keep constant heat blowing at the windshield).

Because your battery will often be "cold-soaked" in Winter, if you drive to an L2 charger a significant portion of charge power will be used for heating the battery instead of charging, until it warms up a bit. I've had this take 45 minutes before with the LR (drove cold car directly to charger 5 mins away). I've seen one graph where the SR+ actually has an advantage here: as long as the charger can supply more than ~4kW (most are 6-7kW), then it will actually actually be charging with the rest of the available power. That said, being left with only 2-3kW is quite slow until the battery has been sufficiently warmed.

If you set the Nav to navigate to a Supercharger, it will preheat your battery on the way so that it can charge faster on arrival. The SR+ heats a lot more slowly than the LR though: the LR can almost entirely use the front motor for heating while using the rear motor for driving. The RWD SR+ probably uses the rear motor to generate waste heat to an extent still, but not as much as the LR, and thus the battery will preheat slower. This only matters if you're nearby: on a long trip, either version should start preheating in time to arrive at the correct temp I'd think.

Coming from being decidedly an EV fan (not strictly Tesla, but here I am), EVs are still a mess in the cold. Combine that with EVs currently being a mess without home charging, I find them hard to recommend for folks in your situation. Some other EVs are known to actually behave better in the cold and in terms of vampire drain; these are potentially better than a Tesla for your case (potentially cold, limited driving, lots of sitting around). Some PHEVs use battery chemistries that tolerate the cold better than a full BEV, but sometimes only for the Canadian versions.
 
I have an SR+ and until recently my condo didn't have anywhere for me to charge. Now I have paid L2 charging in my stall, but my city has so much free EV charging I use it maybe once a month, even less now that it is warm.

Let me specify some things, since of course your mileage will vary: I live in Canada, but a mild part of it. A cold day in the winter is 5 degrees (about 40F for yanks). Very rarely do we get snow here, it was only twice this winter. In the summer it often hits over 25 (around 85F I think). I drive to work 3-4 times a week at my office located 7 kilometers (~4 miles) away. The rest of the days I bike. Two days a week I deliver pizza as a side gig (pays for all my car expenses and a little extra). Total mileage is usually in the ballpark of 300kms or 200 miles. I also do road trips sometimes (my farthest was Vegas). With vampire drain and climate control usage this works out to be about a full charge every week in the summer and a full charge consumed every 3-4 days in the dead of winter.

My experience is your "vampire drain" will vary a lot and with seemingly little reason. Two big factors will make it way worse though: Sentry mode and cold. If it's cold outside and you have sentry on, expect roughly 0.5% per HOUR drain. This means overnight you can easily come back to a car that has lost almost 10%. However, if you have a garage (like me), and your turn sentry off in it, I can often see as low as 0.5% per DAY. Sometimes closer to 1, but if I leave it for 2 days in favor of my bike, I usually come back to only about 1% gone. Also, if is connected to wifi and Data Sharing is enabled (so Tesla can access your car's data), you will sometimes have days where it does an upload and these days seem to chew power, expect a couple percent loss in just a few hours, even with Sentry off.

To sum it up, the biggest drain will be if the car is "awake". You can tell when the car has been sleeping since when you unlock the car the contactors will "clunk" shut. If you open your door and don't hear the clunk, it means the car was awake and likely chewing battery. A pro tip: try to avoid checking your app too often, this will wake the car up, and it usually takes around ~20 minutes to sleep again. Anyhow, those who say you can't live without home charging, I personally disagree. Sure it is a bit of a hassle to walk to public chargers and back, but it's worth it to me to drive without paying a cent for power (what a luxury!). I fully expect free charging to disappear in the next few years, but for now I am content without it. I have traveled over 26,000kms (around 16k miles) and tomorrow will be my 1 year anniversary since buying the car. Had no real problems with charging at free stations, besides it being slightly less convenient.
 
What would folks recommend the minimum charge be when arriving at night, if I needed to leave the next morning unable to charge and the nearest supercharger is 50 miles?

If the nearest supercharger is 50 miles and you don't have a place to charge at home, then I'd not be owning a Tesla!

That being said, you don't live in Philadelphia if the nearest supercharger is 50 miles! In fact, 50 miles means you don't live anywhere near.

There are people who do the supercharging as their only source of charging, but it is debatable how many of them are happy doing that. Think of it as a short term solution - you can buy a Tesla now and put up with the charging headaches. While the car is new, you will be enjoying it and won't mind the hassles too much, but a don't plan on doing that the rest of your life. Look into obtaining a garage with a regular outlet, an apartment with a garage, or even a house.

Personally, I pay $150 a month for a garage. It sounds like a lot, but the overall rent is cheap. I might have had second thoughts buying a Tesla if had to consider an extra $2,000 a year for it, but now I don't mind it. In the same way, you can buy the car and then figure out what to do with it later.
 
What would folks recommend the minimum charge be when arriving at night, if I needed to leave the next morning unable to charge and the nearest supercharger is 50 miles? What's the typical overnight drain, worst case?

I see you are not 50 miles from the nearest supercharger, but just for some reason unable to charge. Well the car's range is 200+, so you should be fine to reach the next supercharger at practically any charge level except near-dead. It is sort of odd to say you don't have time to charge, but then you will be charging at the next location. Charging doesn't take that long, especially the less charge you have, the faster it charges.

You can charge the night before, and also install a charger at your destination maybe, if its only once a year that you need this extra charge.