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Coast to Coast Record has been Broken April 16th, 2015

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Nice to meet you at Primm, Carl and Deena. Congrats! Here's the pic ...
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It's cool, but symbolically it makes me sad that a gas guzzling SUV followed you the whole way. Don't know why that bothers me, but it does.

Congratulations. Wife and I are going to Virginia from Seattle this summer when we get our P85D. Perhaps we will take a stab at the record. Autopilot might make it unfair though :)
 
I wouldn't have taken a SUV. However, guinness requires witnesses, and Time Keepers. Also we didn't have a vehicle that could fit Matt's 6'7 height!

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We didn't exactly draft Nascar style (3" of the bumper). We did say that we used the TACC software when we could.
Carl

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Great job!!

Did you do the St. Charles, MO - Independence, MO gap without and additional need for (slow) charging? If so, what speed did you drive as that gap looks iffy.
We did the trip with only superchargers. We had done larger gaps on our two practice runs, before the attempt. Studied our route, elevation, and distance. Our practice runs (Dec and Jan) were before software updates with charging predictions.

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Met Carl Reese at the Tejon Ranch Supercharger today. Great to hear how they pulled off the record breaking trip. Congrats to Carl, Deena and the rest of their team. Fantastic.

We are happy to meet Tesla owners and hear their stories. Hope to see you soon.
 
Two records were smashed

Congratulations! Of course, records were meant to be beaten. It occurs to me that we're still quite a way from a theoretical time, and that your two records have
conflicting driving strategies.

1. Coast to coast fastest time in an EV of 58 hours and 55 minutes and 25 seconds. Is now the current record held by Rod Hawk, Deena Mastracci and Carl Reese as of April 19th 2015. They have broken the the unofficially time set by edumonds.com on July 16, 2014.

There is a dilemma when you otherwise have enough range to make your next stop -- should you go faster so as to have more time to spend on the charger, or go slower and save charging time?

The fastest enroute theoretical here is when you drive fast enough to consume power at the same rate the charger provides it at, and, well, that's damn fast. I suspect that a 110kW is a lot closer to the redline on the car than the legal limit, so you really want to drive this "gumball style". This also means that you want to leave the charger as soon as the charging rate starts to taper. If, driven like this, you don't have enough range to make the next Supercharger, then things are different. You'll want to take more charge (after the tapering starts) and slow down (to increase range) only as much as is necessary to arrive at zero at the next Supercharger. The two interact as well; if you need to slow to a 70kW draw, you should also have charged to a 70kW taper. The last leg of the trip is driven wide-open, since you are not counting the time to recover the battery to the initial state of charge in the coast-to-coast time.

The proof that this is done right would be that you arrive at each Supercharger empty and spend exactly half of the total time on the trip charging!

So, ironically, you didn't spend enough time charging on your trip!


2. The “Least amount of Non-drive time of 12 hour, 48 minutes, and 19 seconds. AKA total charge time coast to coast.

The least amount of non-drive time trip would be the same as the least energy used trip (and of course, using Superchargers only until the taper starts).
This would be a combination of driving the shortest distance and driving at the best-range speed. Tesla published a speed-vs-range graph here: Range vs. Speed Graph | Forums | Tesla Motors which implies that the optimal speed for this record would be about 22mph. You'd better put that SUV behind you instead of in front!

Since your range would be around 450 miles(!) (less after the first charge, because you'll want to leave as soon as the taper begins), you should instead be thinking about more optimal (shorter distance) routing and skipping Superchargers (when there is a significant off-route distance required to get to one). Of course, this assumes 100% availability of the chargers; so a safer algorithm might be to stop at every one on your route, and if it isn't available immediately, then skip it and go to the next.

Ken
 
Thinking about this some more --

I wonder how fast 110kW sustained would be. Well, let's assume you're only able to use 60kWh or so of that 85kWh battery pack before tapering starts. You'll need to empty this 60kWh in around 30 minutes. What does that imply about the speed? Tesla's graph shows us that at 80mph the range is around 160m, or TWO hours of driving. We don't have power-use data from Tesla above 80mph, we can extrapolate a little; for every 10mph above 80, we lose around 25m of range. So at 100, we'd have a range of around 100, or a power draw of around 85kW (85kWh / 1 hour). At 110mph, we'd have a range of around 75m, or an implied power drain of around 125kWh. (This is simple to measure in a real car, just hold the pedal at 110kW and see how fast it goes, but I'm behind a keyboard now.

So, from this guesstimate, it would appear that we don't need the higher top-speed of the dual-motor cars to get to 110kW. If that's the case, then the best car would be the one that is fastest at 110kW, which, I suspect, might just be a late-VIN, stripped, 60kWh car (we want the lightest car). If the 60 can't maintain 110kW, or doesn't have the range to make it between Superchargers (without tapering) at that speed, then a straight 85 would be best (I suspect that a straight 85 would have better range in highway cruising than an 85D, which would also make the speed at 110kW higher, if this is not the case, then an 85D would be best. Easy test -- whichever goes faster at 110kW).

That would also imply that the optimal speed is somewhat below totally insane (155mph) and in the realm of someone-might-just-pull-it-off (110mph). Since this speed won't be doable 100% of the time, there will be a lot of strategy involved that might make the record change hands quite a bit (and also change whenever Tesla speeds up the Superchargers). These are of course rough numbers, but 110mph with half your time spent charging would imply a door-to-door of around 55 hours.

As far as the second record, I'm assuming that a late-VIN stripped 60kWh would be the lightest Model S built, and that would likely have the lowest energy use per mile and hence be the best car for that trip.
 
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