# Cruise speed vs trip speed



## bwilson4web (Mar 4, 2019)

With the charging curve, I put together a Standard Range Plus Model 3 sheet to predict the trip time (i.e., block-to-block speed) as a function of distance between SuperChargers and the cruise control set speed. According to the model:

85.7 mi - Athens AL to Brentwood TN distance
73 mph - Traffic Aware Cruise Control speed
60 mph - trip speed









So I took a round trip Athens AL to Brentwood TN and back. It wasn't a perfect benchmark:

Arrived at Athens with 25% SOC, more than the 10% target.
Arrived at Brentwood with 4% SOC, less than the 10% target.
Brentwood has a higher speed, 104 kW, SuperCharger than Athens, 100 kW.
Here is the result:









Indicated 73 mph on GPS recording app
Travel velocity was 72.4 mph, close enough
Average trip speed including charging, 61.4 mph close enough

Charging costs:

Athens AL to Brentwood - $2.25, 9 min Tier 2 (arrived with 25% SOC, ended Brentwood at 5% SOC)
Brentwood to Athens AL - $4.93, 17 min Tier 2 (arrived with 5% SOC, ended Athens with 12% SOC)
Total - $7.18 for 171 miles . . . ~2.87 gal of gas @$2.50/gal . . . 59.6 MPG equivalent
Lesson learned: if you put in your next SuperCharger and navigate to it, the charging screen will plan on a 10% reserve (24 mi) and count down to that departure SOC. You can stay on the charger longer for more reserve but having 10% appears to work fine in the SouthEast.

*BACKGROUND*

Recently Bjorn Nyland participated in a 2,781 km (~1,738 mi) in 24 hours, ~72.4 mph dawn-to-dawn speed. For a Standard Range Model 3, we'd have driven +90 mph . . . before addressing the 100-104 kW charging rate. I was just curious.

Bob Wilson


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## Ed Woodrick (May 26, 2018)

While indeed, valid numbers for a single hop charge, you are approaching it from a basic perspective only. It gets a lot more complicated in reality. 
For example, the trip looks to be able to be done with no enroute charging. Charge to 100%, leave and get back home. Even a trip that is beyond the stated range is easily possible, just slow down a little and it is easily doable, probably even 300 miles on a SR. Last I heard, the record on a LR was 600+ miles.

But on regular trips, stopping for charging is the worst thing that you can do. What is significantly more time saving is stopping for breaks at Superchargers. Need lunch? don't stop unless you are near a Supercharger. In a recent trip to Orlando, I made the mistake of letting the girls dictate an early dinner stop, where waiting less than an hour would have saved an hour of travel time, as we could have eaten and charged at the same time, probably even have to remove the car from the Supercharger to avoid idle fees.

Indeed, there was some work done last year regarding the optimal long range trip time and charging. It ended up being around 75 mph travel speeds. That was for a really long trips with a lot more than 1 charging stop.

Even in the SR vehicle, don't look at charging as something that you have to do. Look at charging as something you do when having to take breaks. At around 200 miles, it's time to get out of a car and stretch for a little bit. And it's also a great time to get out and talk to your fellow Tesla owners.


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## bwilson4web (Mar 4, 2019)

We'll have to agree to disagree. My Standard Range Plus Model 3 shows the maximum speed and lowest cost is to charge frequently at LOW, 5-10% SOC. On the first trip of the day, use the maximum range and we're in complete agreement. But my long range trips are way beyond the 220-240 EV range:

*OPTIMUM RANGE*










charge too frequently - the ramp up time delays getting on the highway and making miles.
charge too long - the charge taper delays getting on the highway and making miles.
65 mph - modeled because long distance truckers can always be found at that speed. Less frequently found are 70 mph. Above 70 mph, they don't go because of the speeding fines.
*GRAPHICAL REPRESENTATION OF THE RULES*










*MAXIMIZE HIGH-SPEED CHARGING*









Here is a recorded, SuperCharger session with annotation showing the 'sweet spot.'

*SUMMARY*

First trip start with 100% SOC which means choosing hotel/motels with Tesla distribution and/or J1772 charging stations. When making reservation inform management (above the reservation clerk) that you expect to find the chargers working after you check-in. They may have maintenance turn on the circuit to prevent charger parasites who also take a parking place. Regardless, overnight charging is 'free' and you leave ready for a long leg.
Subsequent segments, put in the next SuperCharger as your destination so the charging display will 'count down' to a 10% reserve. Leave sooner if you know the relative altitudes are descending. A little longer if ascending.
Try to leave when it reaches 60 kW rate to avoid excessive and delays charging at Tier 1 rates.
Bob Wilson


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## Ed Woodrick (May 26, 2018)

I'm not really sure what you are disagreeing with. 

But again, you are tending to miss a LOT of information that needs to be calculated into the mix. At the very beginning, you seem to be quoting the info from 1, maybe 2 Superchargers, there's definitely different results from other Supercharging. Then there's the temperature that will make a difference. Have you calculated the time that it takes to get off your route to a Supercharger into the mix? 
It really seems as if you are focused on the fasting charging speed.
You try to include a best price position, but you don't seem to include the difference in charging rates as the charging decreases below 60 kw

But trust me, you'll have a lot more fun if you just drive the car. I know that I can generally make it from just about any point A to any point B. I also know that, even at Superchargers, my fuel costs are going to be less than most ICE. I know that when I charge at home or free charging, my cost is going to be WAY less than ICE. 
I know that when ?I'm traveling, the BEST way to optimize my travel is to include charging with breaks and meals. 

With the information that I know, that the charging rates and time at Superchargers means very little to me. On a trip from Ft Lauderdale to Atlanta charging has essentially add 0 minutes to my trip. That's a well tested and tried result. 

The thing that I worry with V3 superchargers is that I won't even be able to finish and appetizer before I have to go move the car to keep from paying idle charges.


BTW, you are evidently spending too much time at the Athens Supercharger. Except when heading toward Memphis, you should be able to get to Birmingham or Chattanooga, even Knoxville before having to charge.


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## bwilson4web (Mar 4, 2019)

Ed Woodrick said:


> I'm not really sure what you are disagreeing with.


That is OK. I'm discussing obscure aspects about how my Tesla works. You probably have a different version and my Standard Range Plus, version 19.20.4.2 probably works differently.

The math model is validated.

Bob Wilson


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