Sag, the ability to notify us of inoperable Superchargers is very important, and Tesla needs to develop a notification system for us when we are on the road. However, let's peer about 5 years down the road: I will make the following assumptions, but feel free to adjust them to anything you like. Tesla will offer a 120 kWh for the S and X. The model 3 will come with a 60 and an 85kWh choice. Ranges will vary from 210 miles on the Model 3 60 to 350 miles on the S with the 120. Superchargers will be spaced anywhere from 30 miles in urban settings to a maximum of 175 miles in rural locations.
Okay. In a world with Superchargers every 40 miles I'm not sure if Tesla will bother with 120 kWh batteries, but I don't think it will really affect this discussion one way or another anyway.
There will be no way that any computer algorithm, heuristic or model that will know definitely whether a Tesla driver within x miles of a Supercharger will even stop to charge. Some drivers are just commuting. Other drivers are bypassing one or more Superchargers for diverse reasons. Even others are close to their destination and will charge at another time.
Agreed. There's no way Tesla can be certain if folks driving on their own will pull in to a given Supercharger at any time. (Though it can make a pretty good guess if they go all Big Brother on you and keep track of your typical driving locations and charging habits - but that's also beyond the scope of this discussion.)
It would make more sense to me to have us notify Tesla in advance of our route and our intentions to Supercharge along that route. Then the software can determine based upon our battery when to stop and even for how long. This data would drive the information relayed to us. Commuters and locals need not apply!
It sounds like you haven't entirely grasped what I was talking about - which may not be surprising if the only version you saw was the post in this thread, because I summarized it very quickly here.
My vision for the 5 years from now road trip goes something like this:
Through the phone or voice interface you tell the car you're going to Grandma's house.
The car digs grandma's address out of the contacts list, and grabs your current location.
From the onboard maps it builds a preliminary routing.
It passes that over the cellular connection to Tesla's server, and asks for updates along/near that route.
Tesla hands back current weather, traffic, Supercharger status, and anticipated "reservations" loading of the Superchargers within 40? 100? miles of your path.
The car runs EVPlanner type energy usage analysis on the planned route, using the current SoC and real time weather along with some combination of your historical driving habits and your chosen settings for speed/efficiency.
The car realizes that you won't get to Grandma's house without charging, and based on the settings you've selected previously, it adjusts the route through a series of Superchargers.
As it is setting up the Supercharger string, it notices one that is out of order and another that has 8 people planning to arrive about the same time you might (in the data Tesla passed the car earlier.) Instead of planning for those two, it plans to charge higher at the stops before them and drive right past. It considers what will give you the least overall time, including detours to slightly out of the way but less loaded superchargers. It may even factor in some sort of "favorite locations" list of charging stops you liked/disliked in the past.
Once it has iterated a workable plan, the car passes this back to Tesla, which goes into the server's "reservations" page for other cars to consider as they plan.
Finally, it hands this route back to the driver, with estimated drive and charge times and possibly lists of POI at the various superchargers.
If Autopilot is engaged on the freeway portion of the route, the car automatically shifts lanes to drive itself down the route it laid out, needing human intervention only as it gets off the freeway.
As you pull in to each stall and plug in, the car tells you "23 minutes needed here" or "35 minutes at this stop." (It can't tell you for certain until you plug in because you might end up sharing a charger stack. Once you're plugged in, the time needed should be completely predictable.) There's a screen on the Tesla mobile app that fills with a countdown of the time needed for anyone that's neurotic/in a hurry and off exploring the points of interest.
As you pull out of each supercharger and start down the road, the car updates Tesla's server with new ETAs for its "reservations." (And pulls down updates for weather/traffic/status, which if they change enough might result in changes to future legs of the route - it should probably do this every time it plugs in, too.)
That's the structure I was trying to explain earlier, though I summarized it very quickly. No black magic, not even big brother data mining - just coordinating all of the navigation system travel plans of cars that are driving to known destinations. The car would probably begin attempting to bypass a location when it shows ~80% of the stalls are likely to be full, because as you said there are going to be a number of cars not in the system or not matching the plan no matter what.
Walter