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What do you consider acceptable speed for increased range?

Discussion in 'Model S: Battery & Charging' started by NOLA_Mike, Feb 1, 2015.

  1. NOLA_Mike

    NOLA_Mike Active Member

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    So, over the course of my time here (almost 2 years now) I have seen many posts pop up in all different kinds of threads that seem to indicate to me that some (many?) people here believe that if you don't drive the Posted Speed Limit that you are essentially a hazard to traffic and a menace to others on the interstate.

    I, for one, have no problem getting on the interstate and driving in the right lane at 10 - 15 MPH below the posted speed limit if I need to for the sake of increased range in my Model S. For crying out loud, the PSL is the MAXIMUM you are legally allowed to go - it is not the required minimum speed. There is a minimum speed requirement on interstates in Louisiana but I believe it is 45 MPH (for reference, the speed limit on most interstates in Louisiana is 70 MPH).

    I don't understand the posts that seem to imply it is a crime against humanity to drive 60 MPH in the right lane on a 70 MPH PSL interstate. I used to (pre-Model S) be one of those always pushing the limit and driving 10 - 15 MPH above the PSL, getting uptight and tense because so and so won't get out of the left lane and let me pass. While it may seem like everyone else is going 75 or 80 MPH there are in fact others doing 10 - 15 MPH under the speed limit and you realize this when you actually have to pass someone else going slower than you are.

    Discuss... :)
     
  2. cgiGuy

    cgiGuy Member

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    During my "adventure" over to Alabama, I set the cruise at 60 for the majority of the driving and settled in the right hand lane. Like you, I probably would have been more likely to have set the cruise to 79 in a 70, if range wasn't an issue. But I realized that, aside from the range gain benefit, it made it a virtually stress free driving experience. I essentially ignored the world (within reason) as I can count on 1 finger how many people I actually passed while doing 60.

    The only thing I didn't particularly care for was the action of the truck drivers. They would wait until the last minute (presuming that you were just daydreaming and would speed up any second?) and then get irritated because they couldn't get over due to traffic. I actually turned on the hazards on a couple of occasions because i could identify what type of insects were on their bumper in my rearview mirror. And the funny thing is, in some areas this was still happening when the posted "truck speed limit" was 55.

    Aside from that, it was a very pleasant drive and I now try to apply the same approach (but not 10 under) to my daily driving. I'm pretty sure my blood pressure has dropped significantly. ;)
     
  3. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    I don't get it either. Actually, I try to avoid the Interstates whenever possible but with Superchargers being ONLY on the Interstates (grrrr!), it's hard to do. The silliest driving practice is those who pass you to rush up to the red light where they have to stop and wait--probably fuming because they have to stop and wait. As for speed, the most effective method is to go faster downhill and allow speed to drop uphill. Travel time works out to about the same but the efficiency is improved.
     
  4. cpa

    cpa Member

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    I agree and applaud with the above. Speed limits here are 65, but 70 on rural sections of interstates and SR99 in the valley from the Grapevine to Madera. I drive at the speed limit or slightly beneath it with the exception of passing a string of trucks. I have had a couple of occasions (Blanding to Flagstaff and Kingman to Barstow) where I decided to drive 52/55 on the two lane highways, 66/75 (Arizona) and 64/70 (California) to extend range and not fret over just how close I could cut my SOC to reach the Supercharger.

    I did not have to worry about catching up too quickly to a vehicle in front of me, slow down/change lanes/speed up/change lanes again. The driving was more relaxed with the exception of an 8-mile stretch from the Agricultural inspection station at the California line into Needles. I was driving 64 and a good buddy CHP tracked me in my blind spot until I reached Needles before he punched it and drove off.

    This is rhetorical, but if law enforcement preaches safe and responsible driving, and we are driving a few MPH beneath the speed limit, why is this cause for extended scrutiny? And it does not take 8 miles to check out my car!
     
  5. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    When you see a good looking girl or guy, you might look at them longer than is strictly necessary for identification. I suspect the CHP was doing something similar.
     
  6. eye.surgeon

    eye.surgeon Member

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    Driving at less than posted speeds is dangerous and annoys people. Whether it's morally right or wrong, legal or illegal, is irrelevant to these two facts. It's speed differentials, not speed, that causes most speed related accidents. That means one car driving faster or slower than the others.
     
  7. scottm

    scottm Active Member

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    I consider driving 80kmh an acceptable speed for range preservation.

    Keeping it under 50mph/90kmh really keeps wind resistance down.
     
  8. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    I have absolutely no issue or concern driving slower than the PSL if needed for range. I have never felt in danger or seen any statistics that show slow driving is dangerous.

    My drive between Pagosa and Boulder calls for some interesting schizophrenic driving styles. It consists of two segments, Pagosa to Silverthorne, 241 miles with a stop at a 70A J1772 at Wood's High Mountain Distillery in Salida, then 79 miles to Boulder. Before the 70A J-plug at Woods, it was an interesting Hypermile from Pagosa to Silverthorne, or back; I usually drove Speed Limit + 4 or 53 mph, whichever was less to make it. With the 70A J-plug at Woods, I have found that Speed Limit + 4 or 61 mph, whichever is less works well with a 30-60 min top up and break in Salida. I could drive faster, but the total time goes up because of the time to charge at 50 mph on the 70A J-plug. 53 or 61 on 65 mph roads has never been a problem. I have had occasional honks or flashes, but never felt in danger.

    With Supercharging rates in Silverthorne, the Boulder to Silverhorne segment has no realistic speed limit for time savings, but now, I have gotten into the habit of PSL + 4 and enjoy it. I just remove the 53 or 61 limit.

    Of course, last summer on I-15 in Utah, between Superchargers, I could not resist PSL + X when the speed limit was 80... :biggrin:
     
  9. Beckler

    Beckler Member

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    Interesting that that's exactly the behavior of truckers way up here in Atlantic Canada also. That just cements the idea then that all truckers are compete, unequivocal idiots - every single one of them.
     
  10. dsm363

    dsm363 Roadster + Sig Model S

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    That's not quite fair. There are many responsible truckers. Just as there are bad truck drivers there are horrible drivers of smaller cars and trucks.
     
  11. invisik

    invisik Member

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    I agree. On my trip from Minneapolis to Nashville, I had a leg that was Indianapolis to Louisville where I had a HPWC to use. So I started driving the speed limit to conserve energy to reduce my charging time. I ended up speeding up to match the flow of traffic as other drivers were noticeably upset (and yes especially the truckers). I calculated on evtripplanner that I'd only gain less then 10 rated miles driving the speed limit, so I decided it wasn't worth the aggravation and increased risk of other driver's error trying to maneuver around me.

    I do agree to try to stick to as close the speed limit as reasonable and especially to not overdrive the road conditions.

    -m
     
  12. Beckler

    Beckler Member

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    I hyperbolize of course, and yet any time I've done similar (sitting in right lane following speed limit exactly) almost every single trucker does it. I do notice it because I almost never drive over the limit.
     
  13. LetsGoFast

    LetsGoFast Active Member

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    Driving less than the posted speed limit is often an indicator of someone who is under the influence or transporting drugs. Police often regard this behavior as suspicious.
     
  14. TES-E

    TES-E Member

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    I typically drive 70 on the 75 mph interstate. I almost never get passed by a truck. I often pass trucks doing under 70. I pass quite a few cars too. When I do so and there is someone coming up behind me, I'll speed up to 75 to get around them, then drop back to 70. I also did this in my ICE car. No flashing lights... no getting flipped off... no problem.

    On non interstate roads, I usually run the PSL.
     
  15. MartinAustin

    MartinAustin Active Member

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    LOL OK :)

    I have no problem driving about 10 under the limit, and I actually find many other people doing it. Prior to realising that "driving slower saves you energy," which dawned on me big time when I got this car, I usually was in the left lane doing 7 to 10 over the limit, and always noticed other slower vehicles in the right lane as I passed them. Now that I am in the right lane going slower (usually to experiment with ways to save energy), things are a lot more leisurely and cars are usually passing me to my left.

    When I come across these other, slower vehicles in the right lane, I simply get behind them! Sometimes I'm doing 52 in a 70, which ordinarily I would never do, but if I am following a slower vehicle, no-one can complain :) It's a great excuse to be able to drive slower. Blame it on the other guy.

    I believe no-one should complain at you for driving 10 under the limit on a freeway, as long as you are in the right lane.
     
  16. scottm

    scottm Active Member

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    If the car on 6.1 115 firmware thinks your current charge remaining is barely able to make your nav-to destination, it suggests driving slower.
    But it doesn't say how slow.
    Just thought I'd add this to the conversation.
     
  17. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    Also, I have had many cases I-70 where the car sees the min speed sign and registers that as the max speed limit. Then when the speed limit sign shows up it is one of those variable, lights-in-the-middle signs that the MS does not recognize. Because I have my "warning" set at PSL+5, I guess this means that autopilot software will be driving min-speed+5... :eek:
     
  18. mknox

    mknox Well-Known Member

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    Nonsense. I think the issue is people driving slower than prevailing traffic in the center or left passing lanes. Even before the Model S, I would often drive a bit slower to conserve fuel, but I always stay in the rightmost through lane. If I do move left to pass, I'll move back over to the right when I'm done. I have never had any problem doing this, although I'm not driving ridiculously slow or anything like that. I have found myself frustrated by drivers moving slower in the center, and even sometimes in the right lanes.
     
  19. CanuckS#69

    CanuckS#69 Member

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    I don't ever drive under the speed limit unless conditions warrant, but I certainly don't mind if other drivers choose to do so *if* they remain in the right lane as Mknox mentioned. On a single lane road, it will frustrate people in that you will have a long line of angry drivers stuck behind you if traffic is too heavy for passing. On a highway with multiple lanes, simply obeying the minimum speed limit and keeping in the proper lane is sufficient.

    That said, it is inherently unsafe to have a vast differential in speed between you and the surrounding traffic. I suspect that in some places with more guns than here, it may also be hazardous due to armed road ragers as well. Just think about being courteous to other drivers when choosing your driving speed and keep yourself safe over conserving range.
     
  20. mknox

    mknox Well-Known Member

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    In Ontario, Canada you can drive an EV in the HOV lanes on certain highways. Unfortunately, most HOV users assume this lane is like the German autobahn with unlimited speed limits. You can be going 40 over the limit and still have some guy riding your tail.

    Courtesy is key. Stay to the right if you're going slower and if you do pull out to pass, speed up to the flow in the lane you're moving in to until you can move back to the right.

    On single lane roads, there are often passing lanes or pull-offs to let faster drivers overtake.
     

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