In the 120+ posts in this thread I presume someone's mentioned it, but there IS a pretty good way to get a decent estimate of remaining range. On the energy display if you select average and the range (5, 15 or 30 miles) to average over it will give you a decent projection of your remaining range based upon the average energy use over that range. If conditions (speed, weather, terrain) change it won't help as much, but it's fairly accurate since it's using your past history for future prediction. If you've been driving for 50 miles at 65mph into a 10mph headwind and it's 10F outside, set that to average and 30 miles and it'll tell you how far you can go under those same conditions.
Yes, I'd love something more sophisticated, but the fact of the matter is that without terrain data, traffic data, weight in the vehicle data, wind speed and direction data no projection is likely to be any more accurate (and likely less accurate) than just using historical values as I pointed out above.
The comments above summarize exactly the mistakes made that lead to zero juice and a flatbed finish. Such a bummer. A seasoned owner would never have had this happen, but Tesla really let him down with weak advice along route. To translate this into bullets for
anyone considering a Model S and for anyone ready for a road trip in her/his Model S:
1. Always begin a long trip with a full charge, called a Range Charge, equals about 270 miles for the 85kWh Car. Journalist began with 240 mile standard charge. oops.
2. Expect a 10% range loss in cold weather, higher for the first 30 miles or so.
3. Expect range loss overnight in cold weather, especially until the coming firmware update that will allow for deeper car sleep.
4. Even if there is no "charging station", plug into a regular outlet overnight - range will be maintained or increase a little, and the battery will be warm and efficient in the morning.
5. Driving tips at low charge: Put the car in Range Mode (different than Range Charge), which uses seat heating over air warming, but still keeps you warm. Use cruise control, which is more efficient. Staying close to the car in front of you considerably reduces air resistance and drag. Slower speeds dramatically reduce energy use. Look at your energy window and note your average use for 15 or 30 miles and estimate range using that.
6. Don't go on a trip that is longer than your estimated mileage. I wonder if this reporter was, partly or fully consciously, looking for a story.
I have riven over 3,500 miles in (really) cold weather, including over 1200 miles in mountains far from any superchargers. With just a little forethought and a basic understanding of the car's abilities, such an outcome as this New York Times journalist experienced would never happen. Enjoy -
From the NYT article, it is clear the author is not a EV enthusiast, but the author is part of the Mass market of car drivers.
The Mass Market doesn't want to to read manuals, they've been told the Tesla is "The Best Car in the World" and they know how to drive a car so they don't read a manual. They really don't want to learn a list of guidelines. And frankly there are too many factors that only Tesla knows the answers to and these will change with each firmware release [e.g. Vampire drain from 4.1 to 4.2]. When I tell my significant other I'm planning a long distance drive, I've mentioned factors affecting range like we're gaining 5000 ft over 200 miles, and there is more air resistance at night. The response is an eye roll and proclamation "this is your hobby, I just want a car that gets me there".
Since the EV infrastructure is sparse and EV training limited, Tesla should automate this to alleviate mass market concerns. Consider the following:
1)
Trip Planner - set destination in Nav system [mass market knows how to do this already]. Then a Tesla Trip Planner can do the following in the background: a) knows route - get traffic data - use average speed for the highway - predict effects of stop/go traffic; use external car temp; get Weather forecast for longer trips to get temp by hour; get typography to calc gain/loss. You could have profiles by driver of avg kWh/mi so not dependent on hypothetical EPA ratings. Base range calcs on temperature settings of car. If you can't make it to the destination with the current charge, it should propose charge points optimized around charger capacity to minimize delay. Should check availability of chargers from charge site data (are they operational, available?). Give list of alternative sites. [Similar to Google maps giving you alternative road options]
2)
Trip Monitor - Monitor trip as it is progressing and verify assumptions of kWh/Mi, AC load, etc are correct. If the occupants change any of the controls that affect range (e.g. turn up the heat), redo predictions. If there will be insufficient power to get to destination, provide
early warnings to driver & suggest recourse (e.g. slow down to NN mph; change to Range Mode for heat/AC; Recharge at location xxx, ...).
3)
Park monitor - when car is put in Park, look at temp & weather forecast. See what battery drop will be - pop up screen with factors for next N days - let user change N days so if they are at airport parking lot they can see if they can get home without plugging in.
These are the things that experienced EV people do, but the mass market doesn't want to become an EV person - they want the car to do this. Given the Tesla's instrumentation, connectivity & user interface, this should all be possible to automate. [And for those of you who think this is for sissies, you should have an OFF button in your profile to disable it. But I think the market for sissies is bigger than the market for EV enthusiasts.]
And then when someone ignores all of the warnings and instructions and has to get towed Tesla can at least say "Well the car told you NN times you weren't going to make it... Your flatbed has been ordered."
