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How to plan a road trip - how long will it take?

Discussion in 'Model S: Battery & Charging' started by ChadS, Feb 9, 2013.

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  1. ChadS

    ChadS Petroleum is for sissies

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    #1 ChadS, Feb 9, 2013
    Last edited: Feb 10, 2013
    You probably already have a good idea of how long it will take to drive somewhere based on your experience with gas cars. That part shouldn’t be much different with an electric car. The main difference is charging rather than buying gas. You need to figure out

    · how often to stop
    · where to stop
    · how much charge to replenish
    · how long charging will take

    We will cover those issues one by one below; but before we get in to that, we should have:

    A note for EV newcomers

    Driving electric has many advantages. Smoother, more responsive, quieter, lower center of gravity, less maintenance, cheaper to own than comparable gas cars, cleaner, use US fuel, and all that. However, fully-electric vehicles do have one disadvantage: road trips take longer. That is because charging is slower than refueling - which doesn’t matter for everyday use where you charge overnight in your garage, but can be a drag on a long drive. Fear of this situation is why many people are sticking with gas cars, and missing out on all of the electric advantages.

    However, a disadvantage is not really a disadvantage if you never encounter it – and all-electric road trips are REALLY easy to avoid. First, you can always buy a plug-in hybrid (PHEV), which will electrify most of your driving but still has a gas engine so road trips are unchanged. It doesn’t get any simpler than that.

    You may prefer an an all-electric car (less maintenance, more range, better packaging and less cost than a comparable PHEV), and that's fine because there are still many ways to avoid having to plan an electric road trip. You could take a second family car, rent or swap a car, fly/bus/train, etc. Buying an electric car does not require you to sign a pledge saying you will never use any other form of transport. Not only do many plug-in owners never take a road trip in an all-electric vehicle, but many plug-in owners never charge their cars anywhere other than in their own garage.

    Even though you don’t have to take an all-electric road trip, you may find that you want to. Gas cars are noisy, they vibrate and jerk as you accelerate, the accelerator is not nearly as responsive, gas is expensive and dirty while the solar-powered Superchargers are free…this post is optional reading for those owners that choose to take a long electric trip.

    15702_384521475052_74414_n.jpg
    [Pic: my Seattle-based Roadster in San Diego, April 2010]

    IMG_5483 - Copy.JPG
    [Pic: my Model S in Death Valley, January 2013]


    How often to stop

    The key rule-of-thumb is to never plan to drive farther than 2/3 of your EPA range without charging (although you may alter that plan slightly as you are taking the trip depending on conditions). That’s 177 miles in an 85kWh, 139 miles in a 60kWh, and 95 miles in a 40kWh. For simplicity I will assume an 85kWh car in this post.

    There are many details behind the 2/3 number HERE. With that information you can make some adjustments for a specific trip; but the simple rule of thumb that should cover the vast majority of cases is to not plan your charging stops any more than 177 miles apart. While you may go much farther than 177 miles if you drive slowly on a nice day (300 miles really IS possible), surprise bad weather - including headwinds on an otherwise nice day - could bring your range way down even if you drive conservatively. And when weather conditions are good, the Model S makes it hard to drive slow – but faster driving uses a lot more energy.

    Planning more frequent stops is more work, so most people grumble about limiting trip legs to 177 miles. They grumble even more when I point out even that may sometimes be too far. What if the charger is broken or blocked? You should always leave a buffer for that. Shorter trip legs with more frequent charging:

    · keep you from worrying if you will reach the next charger or not
    · keep you from having to slow down or turn off the climate control
    · give you a lot more options if you run in to a problem with the next charger
    · keep your battery closer to the middle where it is most comfortable
    · give you more breaks from driving (177 miles is 2 - 3 hours; a break is a good idea anyway)
    · help keep any single break from getting overly long

    You can always skip (or more likely, cut short) a planned charging stop if conditions are good and you don’t need it. But plan for it anyway. I tried stretching my range on my first long trip, and had several problems. I learned my lesson and don’t do that anymore; I have since taken 5 long trips (1,600 to 3,000 miles each) with shorter legs and have had no issues – the trips are much more enjoyable that way!

    Where to stop

    Inside your 177-mile range, the primary thing that determines where you make a charge stop will be is the availability of the fastest charger you can access. If you need a reminder of what types of places you can plug in to, what you need to use them and how fast they are, there is a list HERE.

    If you have more than one charging site to choose from, you should take in to consideration what you can do at each location while charging. There is no point to just stand around and wait for your car to charge, so look for things you’d like to do anyway – visit friends, go to a museum, watch a movie, eat, spend the night, read, get some exercise, check email, etc. Charging time is not wasted time if you are doing something you want or need to do. Is the charging location protected from the weather? Are there restrooms, internet access, walking paths or parks nearby? Are there other chargers nearby in case there is a problem with the one you plan to use?

    If you happen to be on the US West coast, HERE is a map that shows you Tesla Superchargers, high-amp J1772 stations, and Roadster HPCs as well as a few “strategic” 14-50 outlets and low-amp EVSEs. You can also use EVSE-finder sites like the following (this is not an exhaustive list; just some sites that I happen to use. No one site has every option):

    · recargo.com
    · carstations.com
    · chargepoint.net – the first charging network to include chargers outside its network. Includes station status for Chargepoint stations
    · plugshare.com – originally a network of owner outlets, now includes public outlets too - so perhaps the most comprehensive overall

    Plus you can look at any number of campground directories that list campgrounds with 50-amp electrical service. (Be sure to ask for “50 amp”, not “240 volt” or “NEMA 14-50” which often cause confusion).

    How much charge to replenish

    The simplest method is to reverse the 2/3 leg-length mantra, and to say that you will charge until you have at least 150% of the miles necessary to reach the next charging point. At least 150% - you really should add an extra ~25 miles in case there is a problem at the next charger and you have to drive to charge somewhere else. For example, if it’s 100 miles to the next charger, you should not leave your current charging station until your car says you have 175 miles of rated range. That may seem like a lot, but just think how nice it will be to take that drive with no worries about getting there! Besides, unless it’s your last charge of the day, any leftover charge will save you time at the next stop anyway.

    If charging conditions are ideal, you may want to stay even longer as having more charge is always better. Well, always better up to the full 240 miles in Standard Mode, anyway. Tesla does not recommend frequent Range Mode charging and charging is slower in Range Mode, so only wait for that if you need it to reach the next charger – or if you are hanging around anyway (i.e. spending the night) and want to use the idle time charging to save time on your next charge. For example if you are at the fastest charger on your trip, and nobody else is waiting for it, and you have things to do there…well, stick around and charge until 240 miles. But if you get bored, or the next charger is faster, or somebody is waiting for this one, you might want to leave as soon as you get to 150% of the miles needed to make the next charger. Perhaps a little sooner if the weather and road conditions are favorable and you don’t plan on going fast; but you should have some road trip experience under your belt before you try that.

    The above describes when you have enough miles to leave. To make an estimate of how many miles of range you will have when you arrive, see THIS post for many details. The summary is to plan to have used 150% of the actual miles from the previous charging point. This leaves you a lot of room to cover bad weather and high speeds. You will hopefully generally arrive with more miles than that; congratulations, you are ahead of schedule. Feels better than being behind schedule, eh? Plan for the worst case, but realize that on good days you can come out ahead. Maybe that extra time will make up for any problems that you can’t anticipate, like all chargers being in use when you arrive. (That has only happened to me once. I talked to the other owner for half an hour and then plugged in).

    How long it takes to get the charge

    The key determinant is what you are plugged in to. The chart HERE gives you nominal rates for each type of charger. As that post notes, your car has to be able to handle the power offered – i.e. you must have Supercharge hardware to use Superchargers, and you must have Twin Chargers to take advantage of 240V EVSEs with more than 40A.

    The general idea behind the numbers in the chart is this: multiply volts*amps to get Watts of power provided by the charger. Then divide by your car’s rated (Watt*hour)/mile to get the miles of rated range that you will get per hour of charging. For example, at a 240V NEMA 14-50 campground outlet, with a 308Wh/mi Model S, you can expect a nominal maximum of 240V * 40A / 308Wh/mi = 31m/h. The number in the chart is actually 29mph because of inefficiencies in the charging process.

    As an example, say you roll in to a campground with 75 miles of rated range left, and it is 100 miles to the next charger. As noted above you don’t want to leave until the car shows 175 miles of rated range. So you need to add 100 miles of range at this charger; at 29 mph that will take almost 3.5 hours. Perhaps even longer if any of the factors below come in to play. Yeah, that’s a long time; that’s why you want to use faster chargers whenever they are available! (My first trip used campgrounds, but I’ve always used at least HPCs since then).

    There are many factors that can lower your charging rate below the maximum values in that chart. They include:

    · The outlet could have lower voltage. This is most common at Level 2 EVSEs, which are 240V when you are lucky, but in practice often on commercial 208V legs. Plus other loads may cause the voltage to sag. Seeing 200V is not uncommon at L2 EVSEs. That will increase your charging time by 20%.
    · It could be lower current. For example, Tesla’s HPWC is rated for 80A when installed on a 100A circuit. But any given installation could be on a smaller breaker, so the current may be well under 80A. There are some Roadster HPCs in Fairfield CA that only allow a 32A draw. What a disappointment; that will more than double the charging time.
    · To protect the battery (when near full in Range Mode, or when it is hot outside) the car may ask for the amp level to be dialed down. You probably won’t notice this with 110V charging; and the effect is usually very small on 240V charging as well if you are charging in Standard mode. It is noticeable with a Supercharger; in fact charging from 20 – 80% may be faster than charging from 90 – 100%. Again, this is only a significant issue if you need a Range mode charge.
    · If it’s hot or very cold, the car will divert power to manage the battery temperature. This matters most at 110V, where in extreme conditions you may find your car not being charged at all. On a Supercharger, this is unlikely to be a measurable drain. For 240V charging in extreme weather, this might increase your charge times by ~30% if you are on a slow 30A EVSE, but 10% is more likely on an 80A HPWC.
    · If it’s really hot or cold and you are in the car with the HVAC on, power will be diverted to keeping you comfortable rather than charging the batteries. On 110V in extreme conditions you may actually LOSE charge. On a Supercharger you might start to notice increased charging times, but the delta should be less than 10%. For 240V charging in extreme weather, the effect of HVAC is probably (I am guessing rather than using real numbers here) twice as large as the effect of battery conditioning. So on a slow 30A EVSE in very extreme conditions, you and your battery may be very comfortable, but you might never get the charge you want. An 80A HWPC may take nearly twice as long to finish.

    In addition to the possible drains on max-speed charging above, charging speed will also ramp down as the battery gets full. Exactly when it ramps down and how far it ramps down depends on a lot of things – type of charger, size of your pack, ambient temperature, pack temperature, etc. Here are some general thoughts based on the type of charging you are doing:

    · 110V: yikes, I hope you’re not using this on a road trip. But 110V is slow enough that you won’t notice a slowdown near the end, so no need to consider this.
    · 240V: The rampdown doesn’t happen until after you get a full Standard Mode charge of 240 miles. In most cases you will stop at that point anyway. But if you need it to ensure you have enough range to reach the next charger, you should figure the miles from 240 to 265 will take about twice as long as the earlier miles (although it varies depending on charger speed and conditions, and is not linear). Figure an hour or so to go from 240 to 265 miles even on an 80A HPWC.
    · Supercharger: the rampdown starts pretty early, maybe even before the battery is half full. But the rampdown is very gradual (so there’s no obvious point at which to stop) and the rate is still very quick. Given the many advantages to having more juice in your pack, leaving early just to make the same charging some minutes faster at the next site is not generally your best strategy. But if you have another reason to leave (bored, others waiting to charge, etc) this gives you one more reason to leave once you have at least 150% of the miles needed to reach the next one.

    The key points

    · Road trips in an EV do take planning…but fortunately they are optional
    · Plan charging stops no more than 177 miles apart
    · Plan to have your range reduced by 150% of the actual miles while driving
    · Charge until your car shows enough rated miles to cover 150% of the actual distance to the next charger, plus 25 miles
    · However long you spend driving, plan on spending very roughly twice that much time charging if you are using a 30A EVSE or pulling 40A from a campground outlet. Plan on spending about the same amount of time charging as driving if you can use 70A HPCs or 80A HPWCs. Plan on spending about 1/3 as much time charging if you are using Superchargers.

    Applying it to a real trip

    In January 2013 we drove from Seattle to Death Valley and back. We spent a couple of days in Death Valley as well as a couple of days in the Bay area; those are ignored for our purposes here to focus on the travel days. We spent four days using Level 2 chargers, and 2 days using Superchargers. Temperatures ranged from 25 to 70 degrees on this trip. Charging was usually done with temperatures in the 40’s, which didn’t seem to have much effect on charging times.

    The Level 2 240V chargers were all Roadster HPCs; 70A at up to 240V. After charging losses ~50mph is probably the fastest charging we’d really expect to see. And few of the chargers are at 240V; most are slightly under 208V which is 14% less so we’d expect more like 43mph. Of course it could be even worse if we sat in the car and ran HVAC, although we didn’t do that on this trip. There also could be some overhead to heat or cool the batteries; on this trip it didn’t seem to get warm enough to have to cool them. It was around freezing several times, but from looking at the actual charging rate it doesn’t appear much if anything was used to heat the batteries – they were probably warm enough to accept an L2 charge (which isn’t very intense on a battery this large) from driving and then from overhead heat released during charging.

    As you can see from the chart below, we actually saw 50mph at the 240V nominal charger (47 the second time, but that included a Range Mode charge that slowed down the overall rate), and 41-44 at the slightly saggy 208V nominal chargers, so the numbers were right in line with expectations.

    As for the Superchargers, there is good news and bad news. The good news is that, yes, they are WAY faster than 70A Roadster HPCs. Probably at least 3 times as fast. The bad news is that we did not get anywhere near 300 miles per hour. Of course we didn’t really expect that much, but our actual rates were between 108 and 167mph, with an average of 139. I was expecting to see 200mph on some of them, and at least 150mph on all of them. I know there have been some threads on Supercharger charging rates, so I’ll have to examine those. I was running 1.15.14 at the time, so it’s possible that contributed. It was also pretty cold for most of the charging we did, though I wouldn’t think that would hurt.

    Day 1 on Level 2

    WhereDistance drivenRated miles usedRated miles at startRated miles at endCharging goal: 150%+25Time consumedRated miles gained per hour of chargeCharging equipmentNotes
    Driving93 miles129 (139%)268

    1:42


    Charging in Centralia WA

    1391851751:0542207V 70A Roadster HPC
    Driving100 miles137 (137%)


    1:43


    Charging at Tesla Portland

    482341834:1544207V 70A Roadster HPCLots to do here, so we stayed longer than needed
    Driving105 miles130 (123%)


    1:45


    Charging in Eugene OR

    104159?1621:2041202V 70A Roadster HPC
    Driving93 miles126 (138%)
    33
    1:30


    Day's totals389 miles



    13:20 (6:40 charging)



    Day 2 on Level 2

    WhereDistance drivenRated miles usedRated miles at startRated miles at endCharging goal: 150% + 25Time consumedRated miles gained per hour of chargeCharging equipmentNotes
    Driving124 miles180 (145%)265

    2:23


    Charging in Yreka CA

    852402583:3344206V 70A Roadster HPCLeft before getting 150% because of elevation loss ahead
    Driving155 miles161 (104%)


    2:28


    Charging in Orland CA

    791881662:1150236V 70A Roadster HPCMeal service was slow so we stayed a little longer than we had to
    Driving94 miles115 (122%)
    73
    1:28


    Day's totals373 miles



    12:03 (5:44 charging)



    Day 3 on Level 2


    WhereDistance drivenRated miles usedRated miles at startRated miles at endCharging goal: 150% + 25Time consumedRated miles gained per hour of chargeCharging equipmentNotes
    Driving94 miles126 (134%)264

    1:29


    Charging in Orland CA

    1382672582:4447236V 70A Roadster HPCRange mode charge slowed down rate
    Driving155 miles200 (129%)


    2:17


    Charging in Yreka CA

    672152113:52 (not charging for ~20 mins)~42207V 70A Roadster HPCGave owner a ride; used ~4 miles of range
    Driving124 miles143 (115%)
    72
    1:55


    Day's totals373 miles



    12:23 (6:16 charging)



    Day 4 on Level 2


    WhereDistance drivenRated miles usedRated miles at startRated miles at endCharging goal: 150%+25Time consumedRated miles gained per hour of chargeCharging equipmentNotes
    Driving91 miles116 (127%)260

    1:29


    Charging in Eugene OR

    1442341832:0344202V 70A Roadster HPCDon't recall why we stayed so long; multiple chargers in Portland
    Driving105 miles124 (118%)


    1:40


    Charging at Tesla Portland

    1101821751:4143207V 70A Roadster HPC
    Driving100 miles128 (128%)


    1:38


    Charging in Centralia WA

    541411652:0043207V 70A Roadster HPCLeft early because we were comfortable with route and weather, and had backup
    Driving93 miles113 (122%)
    28
    1:18


    Day's totals389 miles



    11:59 (6:44 charging)



    Day 1 on Superchargers


    WhereDistance drivenRated miles usedRated miles at startRated miles at endCharging goal: 150% + 25Time consumedRated miles gained per hour of chargingCharging equipmentNotes
    Driving46 miles58 (126%)173

    0:49


    Charging in Gilroy CA

    1151851920:39108SuperchargerLeft early: trying lower SOC
    Driving111 miles142 (128%)


    1:49


    Charging at Harris Ranch

    431852160:51167SuperchargerLeft early: good weather, lower SOC
    Driving127 miles152 (120%)


    1:40


    Charging in Tejon Ranch

    332132491:10154SuperchargerWarm and trying low SOC again
    Driving149 miles188 (126%)
    25
    2:26


    Day's totals433 miles



    9:24 (2:40 charging)



    Day 2 on Superchargers

    WhereDistance drivenRated miles usedRated miles at startRated miles at endCharging goal: 150% + 25Time consumedRated miles gained per hour of chargingCharging equipmentNotes
    Driving70 miles72 (103%)146

    1:14

    Adjusted start miles for cold soak
    Charging in Tejon Ranch CA

    742401991:17130Supercharger
    Driving116 miles150 (129%)


    1:48


    Charging at Harris Ranch

    902171930:54141Supercharger
    Driving112 miles138 (123%)


    2:04


    Charging in Gilroy CA

    792312221:07136Supercharger
    Driving131 miles149 (114%)
    82
    2:00


    Day's totals429 miles



    10:24 (3:18 charging)


     
  2. Frankrb

    Frankrb Member

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    Great stuff! Thanks for your insight and analysis. Looking forward to validating, when I get my MS 85kw next month, travelling from Las Vegas (home) to the Bay Area (daughter and granddaughter) with my "heavy foot":smile:
     
  3. Laumb

    Laumb smrtass.

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    Perfect writeup!


    _____
    Tapatalkin' from iTalatut.
     
  4. Sigma4Life

    Sigma4Life Member

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    Great post! I am jealous that all of your stops are at high rate chargers though. In Texas the best we can hope for is 50 amp service at an RV Park. Superchargers can't get here soon enough!
     
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  5. ChadS

    ChadS Petroleum is for sissies

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    #5 ChadS, Feb 10, 2013
    Last edited: Feb 10, 2013
    Here's one item that I purposely left out of my posting above: advice to slow down and turn down the climate control. Advice like that scares owners into not taking road trips, and potential owners into not making a purchase. Who wants to put up with that? One of the points I was trying to get across was that you don't have to do that. If your charging points are close enough together, you will make it driving the way you want to. I think that's good advice for people trying a trip for the first time.

    But there are a couple of reasons why experienced owners might want to slow down, hypermile in general, or turn down the heater. It's not that you can't make the trip unless you do those things. But going fast and using heat do consume a lot of energy, and if you are stopping at a slow charger, you are going to have to wait for that energy to be replenished. If you are in a hurry, you can save time by using less energy while driving. Slowing down, while counter-intuitive to people in a hurry, is the biggest time-saver if your next charge will be at 240V. Even with a 70A Roadster HPC, 55mph is the "fastest" speed (for a Roadster; I haven't calculated it for a Model S, but I suspect it is similar) - the speed at which time saved by travel speed equals time used by charging. If you go any faster than 55mph in a Roadster, the overall trip gets longer because of the extra charging time. The "fastest" speed is even slower if you will be charging at 40A in a campground. There is a lower bound in the cold though; at some point time-based heater use will matter more than aero drag improvements. In the winter I doubt it ever helps to go less than 45mph, unless you also turn the heater off.

    Plus there is always the case where there is a campground outlet within 177 miles, but there is a Supercharger 200 miles away. You could go full-speed with heater blazing and stop at the campground; but some people might prefer to slow down and turn down the heater in order to be able to skip the campground and head directly to the Supercharger. (Although I always recommend knowing where that campground is just in case things go bad and you aren't sure you will make the full 200 miles).

    None of this applies if your next charging stop is an easily-in-range Supercharger. Drive as fast as you want, the Supercharger will replenish charge faster than you used it. Having the heater on full-blast will slow you down, but only for a couple of minutes - not worth worrying about.
     
  6. stevezzzz

    stevezzzz R;SigS;P85D;SigX

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    Chad, this is a superb précis. It should be required reading for all new EV owners, and Tesla would do well to obtain the rights from you to print it up in a nice brochure and include it in the delivery documents with every Model S they sell.
     
  7. DouglasR

    DouglasR Member

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    Great write-up, Chad. What do you think of this as an overnight charging strategy, particularly in colder weather: dial back the current so that charging completes right around the same time as you plan to leave in the morning. That way, the battery doesn't spend any time sitting in the cold, losing charge. Also, you do not waste any of your battery's energy warming up the battery, which would happen if charging completed at 2:00 a.m., and the battery then just got colder until morning. Finally, it might make sense while having breakfast to use the App to switch to range mode, restart charging, and then turn on climate control and crank up the heat. You can shut off charging before the battery reaches a full range charge so that it doesn't contribute to the battery's degradation, but the idea is to have the cabin warmed up when you start out without using the battery's energy to do it.
     
  8. quartzav

    quartzav Member

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    Won't the battery pack draw from wall plug to keep the battery warm even after the full charge? (As long as the car is plugged in)
     
  9. DouglasR

    DouglasR Member

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    I believe that the battery draws first from its own power to keep itself from getting too cold. If the car is plugged in, it will charge up to the level you have set (i.e., about 240 rated miles for standard charge on an 85 kWh battery), at which point charging is "complete." While charging, the battery stays reasonably warm. After charging is complete, the battery begins to cool. If it cools below a certain level, the battery will draw on its own power to keep itself from harm, and if that causes it to discharge sufficiently, it will begin charging again, drawing from the wall plug. Also, the battery will top off periodically, perhaps every 24 hours, again drawing from the wall plug. But it will not draw from the wall plug to keep itself warm, except when it is charging.

    However, let's say I've driven my car 100 miles, and I plug it in at 8:00 p.m. with a rated range of 140. If it charges at 25 mph, it might complete its charge back up to 240 around midnight. If the ambient temperature is, say, 40 degrees, the battery will then begin to cool down, but it may never get cold enough to engage its own protective warming system. By 8:00 a.m., my range may have dropped to 232 because the car's electronics are never completely shut off. Moreover, once I start driving, the car may have limited power and regenerative braking until the battery is warm again. It will also take energy to warm the cabin. What I am proposing is to have the cabin and battery warm, and the battery complete its evening charge, right around the time I want to start driving again in the morning. That way, I will start the day with a warm car, a warm battery, and 240 miles of rated range.

    This is the way I believe it works, based on observation. I may be wrong. That is why I was asking Chad whether this overnight charging strategy makes sense.
     
  10. napabill

    napabill Active Member

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    I would think that using the app to determine the status an hour or so before departure, would allow you to cause the car to "top-off." This can be done by changing the setting on the app to range charge. It will then start charging again.
     
  11. ChadS

    ChadS Petroleum is for sissies

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    DouglasR, yes I think your strategy of lowering the charging rate when staying overnight so the charge finishes shortly before you leave is a good one, and in fact I usually do that. It's also more grid-friendly to pull at a lower draw, is less likely to pop a breaker, and keeps from generating excess heat in the summer months. The only real downside I see is if you are at the only charger in the area, and somebody else comes in late at night and wants to use it. To reduce pain if that happens, I will try to charge full-speed for a while to get a fair bit of charge, and only turn the rate down right before I go to sleep. And I leave my cell number on the dash. (Someday there will be enough chargers everywhere that we don't have to do that; but I think we'll get to that day faster if we are all careful to make sure we are not blocking other owners in the mean time). That's also a good argument for trying to pick a hotel with more than one charger.

    Using the smartphone app in the morning sounds great too, although I have never had that capability in an EV on a road trip - now that we have it for the Model S, I'm looking forward to trying it on the next one. I assume it will work the way we want, but Tesla seems to be careful about not describing exactly how things work - partly, I suspect, so that they can later change the behavior if they like.
     
  12. Puyallup Bill

    Puyallup Bill Member

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    Thank you very much for the excellent article. I am planning a few trips this spring and for you to make the effort to share your experiences is greatly appreciated.

    I've done some planning for short trips with the LEAF, but with its 3.3 kW charger, there are not many options. Dummy me, to save a few bucks, I did not get the CHAdeMO port. I've learned my lesson, and am getting the model s with dual chargers.
     
  13. toto_48313

    toto_48313 CAN P #5

    Joined:
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    Montreal suburbs
    Great article. It's interesting to see that the average is about 35-40 mph including charging time....
     
  14. DFibRL8R

    DFibRL8R Member

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    Location:
    Leesburg Virginia
    Doug R's strategy makes sense in the winter but is the opposite true in the summer? Would we want to finish charging earlier to allow the battery to cool down prior to use to avoid unnecessary active cooling of the battery while driving on a hot day?
     
  15. Laumb

    Laumb smrtass.

    Joined:
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    Lost in Norway
    You only need to consider having 175 miles longer to travel on a 100 miles left charge. ;-)

    :p


    _____
    Tapatalkin' from iTalatut.
     
  16. ChadS

    ChadS Petroleum is for sissies

    Joined:
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    2,401
    That's a good question. I don't have a solid answer with numbers to back it up, but here's my impressions.

    First, being too hot is not as big of a deal (at least not in terms of charging times and driving range) as AC is less of a hit than heat.

    Second, being too hot is a bigger deal for battery life. So while it would be nice to have some spare time to let the battery cool before driving, you don't want to do that at the expense of getting the battery really hot because you are charging it so fast. Then again, with an 85kWh battery even 240V 80A is not very fast (and presumably you're not plugging in to a Supercharger overnight). So perhaps it's not a huge deal either way.

    In hot weather it may indeed be a good idea to have your overnight charge end a little early so the battery can cool before you take off. But I don't think it will be a huge difference if you don't; and lowering the charging rate is still good for all the other reasons listed above. You just don't want charging to finish immediately before leaving.
     
  17. Zapped

    Zapped Model S - PURE EV

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    Thanks ChadS, invaluable information.
    I was planning a road trip but good thing it didn't happen until I read your post.
    Unless I missed it, could you tell us where you stayed overnight to have the full charge at the start of each day ?
     
  18. ChadS

    ChadS Petroleum is for sissies

    Joined:
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    #18 ChadS, Feb 14, 2013
    Last edited: Feb 14, 2013
    On the L2 days between Redmond WA and Davis CA, I spent the night in Canyonville, OR. The Seven Feathers Truck and Travel Center has a Roadster HPC. They also have a CHAdeMO station, a 30A J1772, and a campground with a ton of 14-50's. And a Casino with a nice hotel, and free shuttles between everything (though I just walk; it's only 1/2 mile).

    At the end and beginning of the L2 days in Davis, I stayed at the Econolodge in Davis. A few blocks away is a parking garage with a 70A J1772. They also have a 30A J1772 and a small-paddle charger for old RAV4-EVs.

    One Supercharger day started in Palo Alto from a hotel that wasn't near a charger; but while I was at a board meeting the previous day my wife had charged up at Tesla headquarters. That day ended in Barstow; we got a Standard charge at the Supercharger then went to the Rodeway Inn in Barstow. In the morning the first thing I did was put the car on the Roadster HPC at Barstow Station for a Range charge while we ate breakfast, showered and packed. The Rodeway is several miles from the Supercharger, but about 1/2 mile from the HPC.

    The other Supercharger day started at a hotel in Mojave CA. We didn't charge there; but the previous evening we had gotten a full charge at the Barstow Supercharger, so we had plenty to make it to Lebec. That day ended in Davis again.

    There were also a couple of days in Death Valley; the Furnace Creek Ranch has 14-50's in the RV park.

    All of the above locations (well, the ones with chargers, anyway) are on my West-Coast "Tesla Highway" map HERE.
     
  19. Zapped

    Zapped Model S - PURE EV

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    Thanks, the TESLA Highway Google map is great.
    I was planning my trip around the HPC locations on your map and had purchased the orange HPC to Model S cable before I took delivery of the car.
    Also had planned on overnight stays a hotels with charging stations to optimize my time on the road..
    I'll have to revisit the route and duration for a September departure from Edmonton, Alberta, over to Vancouver, BC and down the I-5 over to Palm Springs.
     
  20. TsRocket

    TsRocket Member

    Joined:
    Nov 21, 2012
    Messages:
    244
    Location:
    seattle
    This primer should be GIVEN to every new Model S owner .... Printed and in a nice leather packet with their owners manual. Wish i had had it before i zeroed my car out on the first trip, one day after receiving the keys. THANK YOU.
     

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