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6.2 Trip Planner - Observation: Keeps you above 20% SOC?

Discussion in 'Model S: Battery & Charging' started by arijaycomet, Apr 5, 2015.

  1. arijaycomet

    arijaycomet Member

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    IMG_9499.JPG

    Driving home today from the in-laws after our Easter holiday celebrations, pulled up Nav and put in Home as our destination. Our route home goes right past the Macedonia Ohio supercharger location. As you can see in this photo, it was telling us to charge for just 10 minutes. What it important to point out was that when I removed charging, it had us getting home with 17% SOC instead of the 22% SOC that we'd have had at the SC.

    We did not stop (the $6-10 savings charging there was not worth my time today, though we have before). But I'm looking at this as perhaps a verification that the trip planner saw stopping as a sensible action, because the car was going to otherwise drop into the yellow (under 20% SOC). Has anyone else found similar results?

    Overall I guess that makes sense, but the car would know that my home has a charging station. And the way Trip Planner and such are described in the update, it seems like it would know well enough to not have me stop and waste 10 minutes since my final destination coincides with a known charger. AT least, that how I view it.... so yeah, wanted to share this interesting finding.
     
  2. commasign

    commasign Active Member

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    I wish it would give us the option to specify how much "buffer" we want as well as how fast we plan to drive. It could make the difference between stopping or not charging for legs in 175-225 mile range.

    - - - Updated - - -

    Come to think of it, does anyone know if the speed limit offset in the speed assist menu affect the trip planner and energy graph calculations?
     
  3. RiverBrick

    RiverBrick Active Member

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    In the press kit for the release there's an image where the software has one go from Grand Junction to Silverthorne non-stop, skipping Glenwood Springs. This is 181 miles with an elevation gain of 4,200 feet. In most circumstances, this will leave you well under 20%.

    It might be reading too much into a possibly old and contrived image, though.


    software-6-2-la-to-ny.jpg
     
  4. andrewket

    andrewket 2014 S P85DL, 2016 X P90DL (soon 100)

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    Yep, I think 20% is the magic number. I had a similar experience driving from Pittsburgh to Baltimore. Trip planner wanted me to take a 40mi detour via Hagerstown. I deleted that stop and drove direct, arriving with 15% left also at a destination where I have charged before. We need more control over the assumptions (Elon will hate this- it's "unneeded complexity"). I'd also really like waypoints, not just for convenience but also so trip planner can take the entire trip into account when making charging decisions.
     
  5. JohnQ

    JohnQ Active Member

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    Yes, 20% is quite a large buffer ... about 50 miles of range remaining. There are quite a few places where supercharger placement is allows you to reach the ned one within that 50 miles and it's better to reach a lower state of charge. Not to mention the cases where your final destination is within that buffer.

    I'll be using EVtripplanner for quite a bit longer until I become comfortable with the calculations performed by the Tesla trip planner.
     
  6. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    See the thread at "A review of the Trip Planning Tool."

    When I did the analysis matching EVTripPlanner's needed range, and used the assumption that the MS Trip Planner wanted a reserve of 20%, I got consistent charge times at Superchargers.

    It very much seems that the MS Trip Planner computes for a 20% buffer. It is also apparent that it optimizes for the minimum number of Supercharger stops and not for minimum total drive plus charge time with more stops.
     
  7. Vger

    Vger Active Member

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    This seems reasonable, but very conservative, if and only if, as Elon stated on the call, that the new prediction system was designed for 1% accuracy in energy usage calculation.

    With 6.1, I found myself usually holding at superchargers for the 20% ending margin at the next stop, but only because I felt the first-generation prediction was not reliable in the face of bad weather and/or headwinds.
     
  8. artsci

    artsci Sponsor

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    That seems to be reflected in my experience yesterday.

    I left home from the Batlimore area with about 230 miles of range. Drove to Glen Drive in Alexandria, VA then on to the Officer's Club at Fort Belvoir with two side trips into downtown Alexandria. When I left Fort Belvoir and used the trip planner, it wanted to divert me to the Bethesda supercharger. I had about 130 miles of range left and knew that a direct route without a stop in Bethesda would be 83 miles. As it was a warm day, based on my experience with the car I concluded that I had an adequate margin, so I skipped the stop in Bethesda and took the direct route home. I avoided my usual lead foot driving style and followed the flow of traffic at or near the posted speed limits. I arrived home with 13 miles of range left. This with two passengers.

    So my mental trip planning calculator was spot on. If it was a colder day with bad weather I would have taken the trip planner's advice.
     
  9. Morristhecat

    Morristhecat Member

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    This 20% buffer reflects my experience too. The other day I routed a trip to the Hope BC supercharger, but perhaps due to my state of charge not being very high, it routed me on a 3 hour detour accross the US/Canada border, to the Burlington WA Supercharger where I would have arrived with 29% charge, and had me charge for so many minutes. Then it sent me back accross the border a 2nd time, and on to the Hope BC supercharger, where I would have arrived with 25% charge. Add that to the border wait times, I am sure it would have been at least a 5 hour detour. It was the most unbeleivably dumb routing I could have imagined - completely nuts!

    So I turned off the automatic charge routing, and I would have arrived at the Hope Supercharger in about 2 hours with 17% charge - no brainer. That seems to hover around the magic 20% figure nicely. So no matter how rediculous it seems, it can make you do some wild side trips. One has to scrutinize the routing carefully if you don't want to waste your day away - Don't just blindly drive! It would be better if there was a way to add to the cars charger database some public 80amp AC or Chademo DC chargers (even manually).
     
  10. andrewket

    andrewket 2014 S P85DL, 2016 X P90DL (soon 100)

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    This has not been my experience. I've had one occurrence thus far of the trip planner having me stop at 2 SCs when I could easily make it to my destination from the first SC if I just charged a bit longer.
     
  11. ruby110

    ruby110 Member

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    We haven't seen this 20% buffer. To the contrary, what we keep seeing in a multiple SC trip is the planner tells us to continue our trip with very low reserve. For example, when we arrived at an SC it said we would charge for 40 minutes. But then after 5 or 10 minutes it said we could continue to the next SC with a 1% reserve. One time it said we could continue with a -1% reserve.

    Anybody else see this behavior?
     
  12. Candleflame

    Candleflame Member

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    is it really that bad to drive the vehicle down to 0% if you will resupercharge it straight away? Ive heard that going above 80% if the top 20% get used up immediatley has pretty much no measurableeffect on long term capacity loss. What about going below 20%?
     
  13. tliving

    tliving Member

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    Is it me of would it just be helpful if Tesla explained how it actually worked so we weren't second guessing the thing?
     
  14. stevezzzz

    stevezzzz R;SigS;P85D;SigX

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    Using the new route charging planner in 6.2., every route I've tried going west from my house has me bypassing Silverthorne and arriving at Glenwood with 11% remaining. So 20% is not a magic number.
     
  15. apacheguy

    apacheguy Sig 255, VIN 320

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    Does 6.2 allow the option to remove SpC from the route?
     
  16. andrewket

    andrewket 2014 S P85DL, 2016 X P90DL (soon 100)

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    Yes.
     
  17. mikeash

    mikeash Active Member

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    The trip planner is definitely funky at the moment. I'm driving from Fairfax, VA to Williamsburg, VA this weekend. There are two superchargers on the way, one in Woodbridge and one in Glen Allen. I don't know if I'll be able to charge at Williamsburg, so my plan is to charge up at Glen Allen enough to have a substantial buffer for Williamsburg and back to Glen Allen, and if I feel like waiting around see if I can put enough charge in to make it all the way back home in one shot.

    I put it into the car this morning to see what it would advise. It suggested going to Woodbridge (which is only about 20 miles away), charging for 50 minutes (!) and then going straight for Williamsburg after that. The same amount of charging could be done at Glen Allen in much less time (since I'd be at a lower SoC by then) and there's a substantial buffer to make it there (the car predicts ~50% charge remaining upon arrival there).

    Hard to tell what's going on. I like the fact that the car has this stuff and it seems like it will keep you from getting stranded, but there's still quite a bit of room for better planning.
     
  18. sublimaze1

    sublimaze1 8Dec2012 / Leeroy Jenkins

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    +1

    I (before this update) used to mentally calculate what I had left based on where I was going, how much consumption (e.g. lead foot, head wind) was occuring, and distance left. In fact, for the 5 hour drive to my bro's house, it was enough mental work to allow the drive to go by quite nicely.

    Also, I plotted a trip from Plano (TX) to Bastrop (TX) - going to see MotoGP in 47 hours ten minutes (but who is counting)

    They had me going down 45 to Corsicana then back roads to Bellmead then off to Bastrop ... when I know I can head straight down to Bellmead with 90 left on the range meter then boost to 225 for the rest of the 100 miles (about 2/3 of it is at 90mph).

    I find that the calculations the car does is in the best interest of those who fail to pay attention or calculate their distance. But, as artsci said, using your noggin' can be useful (okay, that's not anything like what was said but ... anyway ...).
     
  19. 1101011

    1101011 Proud TSLA/SCTY shareholder since 2012.

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    Not sure how 6.2 is working. I was headed out of an eastern Cleveland suburb, bound for Madison WI, starting with a 90% charge which easily would get me to Maumee for the first leg. It kept telling me to detour south to the Macedonia SpC and charge there first. I did not find a way to eliminate the first supercharger in the trip planner. Perhaps someone can instruct me on that?

    As an alternative, I skipped the trip planner until I was well west of Cleveland, and re-input the destination. Seemed to work at that point.

    Wouldn't hurt if TSLA would post what the TripPlanner's logic is.
     
  20. andrewket

    andrewket 2014 S P85DL, 2016 X P90DL (soon 100)

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    This is from memory, so it might be slightly off. Hit the blue trip button which will then display the charging locations. You can selectively remove a SC or remove all charging.
     

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