Best speed for road trips?

[KaptKamp]

What is the most optimal speed for a Model 3 on a road trip?

I have been trying to figure out the answer before a cross country road trip and it is not a simple question. Traditionally, with an ICE car the faster the better because they can refuel at +6,000 miles of range per hour. But speeding in an electric is somewhat counterproductive, you use up your range faster than you can make up for it with more frequent charging. So... what is the ideal speed to travel the most distance in the least amount of time on a trip requiring many charging stops?

In my brief research using abetterroutplanner.com it seems that 74 mph is the ideal speed but I am curious if anyone has some more concrete data to support this.

 

[RichardL]

There was a lot of analysis done in the early days of supercharging - basically, as long as you can reach the next supercharger, you should drive as fast as you dare. It gets you to the supercharger quicker and with a lower battery %. The supercharger adds range faster than you use it/lose it through driving which more than offsets arriving with a higher SOC.

There were some fairly complex mathematical analysis-es done, but 'faster the better' always was the underlying message

 

[Silicon Desert]

Based on my cross country trips, I'd say it is pretty much the same method for any model, not just the 3. You'll find that out after a few charges at different SCs. And keeping mind that once you get above 80% to 85% of charge, it is going to cost you a lot of extra time to get that additional 15-20%. You might as well get back on the road. Of course, other conditions can limit your charging as well. "The faster the better" isn't going to work with the Tesla. I guess you know all this. Yup, I usually keep my speed in the range of 70-75 but depends on the speed limits and conditions. So for me in my X100, I have found that my trips actually take about the same amount of time if I take a couple more SC stops after charging up to about 85% instead of trying to top off the juice. And the plus is that I get more time to rest at those stops.

I don't agree with the "faster the better" approach, yet some do.

 

[Matsayz]

The speed limit of that road? I'm kidding. Going 5 mph over the speed limit when you are traveling across the country can add up, but it is only a fraction of the total time spent. Just use AP while on the highway and set it so you don't get run over by people.

The real savings are like the posts above saying don't sit at the chargers just to get back up to 90% unless that's what you need to get to the next charger. If you haven't I would suggest changing your miles until empty to a %, it alleviates range anxiety amongst most that make that change. The car doesn't have all the data input that A Better Route Planner can provide (weather/weight/way points) but it does do a damn good job I think of getting you to the destination with what it originally told you it would. The car also adjusts the expected arrival range with how you're driving. In my SR+ I'm cool with getting down to about 10% or so to arrive at a supercharger when doing a long trip, that's about 24miles of "oh crap we missed the turn".

Download PlugShare if you haven't as well, select your type of vehicle and which charging types you can plug into (J1772 adapter comes with the car but is gonna be slow). I would suggest trying to buy a 14-50 adapter for the charger that came with the car (don't forget to take that with you btw). Also remember that some RV parks will rent you a spots (sometimes cheaper since you aren't staying too long but normal price is $20-35) and this is where that 14-50 NEMA adapter for the UMC (mobile connector that comes with the car) would come in handy. Yes that's a ton of money when a supercharging session would probably be like $7-10 but it's cheaper than a flatbed tow truck!

What's the destination and which Model 3 trim do you have? Post some more details and people will hopefully chime in with helpful answers

 

[Dolemite]

when in doubt, flat out

 

[1.21GW]

Agreed, fastest travel speed will save the most time. If you are trying to minimize overall travel time.

 

[MasterC17]

Fastest (reasonable) speed to get to the next Supercharger. I generally try to arrive with <5% SOC and charge to 50%-70% to arrive at the next leg with <5% SOC. This is the quickest way to do it. My best was 623 miles in 10 hours.

Essentially, the Supercharger will add miles faster than you will drop them off driving. Unless you are driving WAY above US speed limits.

 

[SageBrush]

In my brief research using abetterroutplanner.com it seems that 74 mph is the ideal speed but I am curious if anyone has some more concrete data to support this.

The App does not know the weather.

Do this:
1. Tell the car you next SC destination
2. Leave when the car tells you to, and drive ~ the speed limit
3. When 1/4 the distance remains, drive faster if you have excess energy (meaning arrival SoC > 10%)
4. DO NOT drive in a fashion that has the car telling you that you will arrive with less than 10% SoC unless you are close to the destination. If it happens, slow down until the arrival SoC is > 10%

Does anyone care about the math ? It is pretty straightforward if thought of as a min/max problem. Solve for
f'(t) = 0. Aero forces vary with the square of the speed, the other forces are ~ proportional to distance except for AC, and there is ~ a 5 minute overhead penalty for each SC stop. If you are going to hit each SC regardless then the problem simplifies to speed related energy consumption and time related AC use.

 

[outdoors]

From 6 or so 1100-1200 mile solo 24 hour drives. Faster is better. If I pick a few points right I could easily now do 1300 miles. Yet you have to really know the chargers if you want this type of outcome. @MasterC17 is right on. Not for the faint of heart, but I run to 5% with no hesitation now. Almost never leave above 75%.

Yet this is not enjoyable. It is almost painful.

OP says what is the most optimal? Depends what you want. Speed or efficiency.

 

[KenC]

What is the most optimal speed for a Model 3 on a road trip?

I have been trying to figure out the answer before a cross country road trip and it is not a simple question. Traditionally, with an ICE car the faster the better because they can refuel at +6,000 miles of range per hour. But speeding in an electric is somewhat counterproductive, you use up your range faster than you can make up for it with more frequent charging. So... what is the ideal speed to travel the most distance in the least amount of time on a trip requiring many charging stops?

In my brief research using abetterroutplanner.com it seems that 74 mph is the ideal speed but I am curious if anyone has some more concrete data to support this.

Interesting. I looked into that question last year, using ABRP, and my recollection was that faster was better. Much faster.

Looking now, Maine to LA, at 100% Reference Speed is 56hrs, 110% is 53hrs. 120% is 51hrs. 130% is <50hrs, so yeah, like last year, it seems that ABRP says faster is optimal.

 

[Xambler]

Catch a good tailwind and you will be amazed how much that improves your mileage. Makes sense that if you have a solid 10-15 mph tailwind that you can get about same mileage at 75 with tailwind that you would get around 65 otherwise. Basically I just go the speed limit on long trips...maybe 5 mph over. Except in Atlanta where even 15 mph over speed limit will get you rear ended.

 

[mikeskuro]

I did a 1000 mile door to do drive from VT to NC and back a few weeks ago. Cool on the way down(40s to 60s). Warm on the way up 70s-80s. Temperature and wind make the most difference. 299kwh, 299wh/mi on the way down and 255kwi, 264Wh/mi on the way home. 17 hours, averaged 62.5MPH, including charging stops on the way home. I was hauling ass. But quite efficient if you ask me. Aero's, OEM primacies and a 5 year old kid in the back seat.

Trust the trip computer and don't worry about charging.

 

[Chisale]

What is the most optimal speed for a Model 3 on a road trip?

I'm going with 145mph, the maximum listed speed of the vehicle. Though dodging traffic and speed radar might make the trip a little stressful. I just hope the roads in your area are better than in mine because around here you can barely do 75 without having both hands on the wheel.

 

[Matsayz]

The App does not know the weather.

Do this:
1. Tell the car you next SC destination
2. Leave when the car tells you to, and drive ~ the speed limit
3. When 1/4 the distance remains, drive faster if you have excess energy (meaning arrival SoC > 10%)
4. DO NOT drive in a fashion that has the car telling you that you will arrive with less than 10% SoC unless you are close to the destination. If it happens, slow down until the arrival SoC is > 10%

Does anyone care about the math ? It is pretty straightforward if thought of as a min/max problem. Solve for
f'(t) = 0. Aero forces vary with the square of the speed, the other forces are ~ proportional to distance except for AC, and there is ~ a 5 minute overhead penalty for each SC stop. If you are going to hit each SC regardless then the problem simplifies to speed related energy consumption and time related AC use.

I was on the site earlier today and I think weather is one of the premium options now. They must’ve gotten popular enough to start charging. Weather and Live chargers status, not sure how their pulling that info tho

 

[TheWhiteEGG]

Probably speed limit while drafting.
Can look at my previous posts and see the data I logged in on the model 3 during road trips.

 

[Big Earl]

Bjørn Nyland calculates it at around 105 MPH, if I remember correctly. You can play with the speed function on A Better Routeplanner and see what works best for your particular trip. While I don’t travel anywhere near that fast in the USA, I’ve found faster to be better, and I almost never skip a Supercharger unless it’s a long diversion from my route or it’s an urban Supercharger.

 

[kysrsoze]

It’s 80. This car drives so well at 80. I figure it’s somewhat of a drop in mileage, but you get somewhere quicker and it’s enjoyable.

 

[Zcd1]

There was a lot of analysis done in the early days of supercharging - basically, as long as you can reach the next supercharger, you should drive as fast as you dare. It gets you to the supercharger quicker and with a lower battery %. The supercharger adds range faster than you use it/lose it through driving which more than offsets arriving with a higher SOC.

There were some fairly complex mathematical analysis-es done, but 'faster the better' always was the underlying message

This is the correct answer.

 

[PJFW8]

This is the correct answer.

I agree 100%. The only exception is the occasional big distance to the next supercharger.and weather issues, of course. Out of Spec Motoring has demonstrated this in numerous long drive videos.

 

[jpfive]

Thanks to all for the useful contributions to this thread. I've enjoyed it. Timely, too, as I go coast-to-coast and back in a couple of weeks. In my trips to Tallahassee and back (400 mile round trip) I've settled on speed limit plus 3, which lets me do each way non-stop. If I push it to 80 I pay a trip to scenic Defuniak Springs for a cup of coffee and a Danish.