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Emergency Road Service Charging
- Thread starter SantaFeSpence
- Start date
i dunno... maybe... $150-200 a tow versus $50 getting a quickie charge off an EV tow truck, not unlike the ability of the Cybertruck to power electrical tools...
You're forgetting an extra 0 there. $500 might be getting nearer to the right order of magnitude. $50 per service call for a single purpose piece of equipment that would only be used a few times a month is fantasy.
Two scenarios with respect to the equipment:
1) You use the example of the Cybertruck. OK, with a 240V system, that would be cheaper equipment in the charging truck. But then that means they need to sit there on the clock for a couple of hours waiting for someone's slow onboard 32A or 48A charging to add enough miles. Time is money, and they are going to charge extra high for wasting their time that long.
2) The reasonable charging speed for quick emergency situations would be like a CCS or CHAdeMO. So then that would need a significant sized battery bank onboard the truck to supply the energy to drive that DC fast charging system. (Extra $$$$$$). And then how would they recharge that battery bank after charging up a customer? They have to spend even more time on the clock to refill that, which they would have to pass on in the customer charge.
Come to think of it, $500 wouldn't be a high enough rate for this kind of service.
all speculation, but I think you are too pessimistic about the possibilities. I didn't mean to suggest that an *unaltered* Cybertruck would be a good idea. Basically, an EV tow truck would have a feature to be able to dump say 10% of its charge in 10mins in DC mode (not 240VAC) into the dead EV. I don't think that's $500 worth of service.
This is NOT true. You absolutely can run out of charge "listening to the car."
Be smart about it and pay attention to the energy usage for the last 50 to 100 miles before your supercharger visit (unless you have superchargers that are less than maybe 100 miles away.)
It's less likely on a LR, but if you only need to go 150 miles and are at low SOC, the supercharger might suggest you depart at like 60% charge. If it's winter (cold), raining (standing water on the road), and windy and highway speeds, you might actually need like 80%+ to make it.
I recently had to figure this out with my SR+. I had a 140 mile gap between superchargers (and only one level 3 charger at 25kW and I didn't have the adapter) and it was cold, raining, and a little windy while at highway speeds. The Dalles supercharger said to leave at like 72% or something but I had been watching my previous energy usage in these conditions and KNEW that I had to charge to at LEAST 94% to make it. I charged to about 96% and had less than 10% when I got home (and part of the 140 miles the rain had stopped).
So basically, be smart about it and know how many wh/mile you've been using in the current conditions and know that 100% of the battery is ~75,000 wh. Then if you need to do 150 miles and have been averaging 375 wh/mile you know you need 56,250 wh (56.2kWh) or 75% (56.2/75) of your battery. Then it's probably safe to charge to 80% before leaving so you don't hit 0% when you get to your destination.
By the time the estimate has sufficiently degraded and realises you won't make it to the next charger, your best hope might actually be to backtrack if you're not in a Supercharger-dense area. Not great.
I got "into trouble" while constantly checking the trip graph and making adjustments. But that's just it - why are adjustments consistently necessary in the cold? Because it's not accounting for the cold properly. I didn't have to change the ABRP estimates at all in order for it to get me to my destination with the expected charge within 1% of estimated.
Exactly. Don't look at the stated remaining range showing on the car, the navigation estimate, then drive like a maniac and be surprised at how it plays out
It's tiring that this type of conversation always devolves into this specific hand-wave.
Is driving at 70mph in an 80mph zone at 5C (41F) with no wind "like a maniac"? Yet this is a scenario I consistently came across over two days that the trip planner could not deal with. Driving any slower in an 80 zone would be more of a maniacal choice since I'd be impeding the flow of traffic (where I'm from, you can actually get a ticket for this because it's dangerous).
It's interesting that when this comes up on Reddit, most agree that the trip planner does not effectively account for cold. Bring it up on here, and most say it does so effectively.
Wait a second. This adjustment and revising of the estimate will play out in the first 10-15 minutes of your driving, as it starts accounting for your heavy heating use. So you can't really be "not in a Supercharger-dense area" if you just left it 15 minutes ago.
I am starting to wonder what tool you are actually referring to as "trip planner" that is giving you so much trouble. Are you talking about the trip planning utility on Tesla's website? Most people have found that to be kind of hokey and not very good. But if you are talking about the in-car Navigation % remaining estimate, that is usually really close if the temperature is at least above freezing. When it's getting below that, sure, it needs some common sense compensation. If the car says "ready to go" with only a 10% remaining buffer, and it's well below freezing, I guess I take it as a pretty simple thing someone would learn once that it is not going to be enough, and you should start off with more like 20%.
Yeah, that was scenario #2 that I described--much more expensive equipment for portable DC fast charging with a big battery bank.
? every EV has a big battery bank... it can afford to sell of 10-30% of it to quickie charge customers at little equipment costs.
My graph often revises when I'm about 40 to 50% into the trip, usually it's by 5% or less, but it certainly does some more changes deep into the trip.
The navigation doesn't do a good job of estimating when there is additional power draw. I think the issue is most people plug it in while at a supercharger or before they reach a supercharger. If you cancel it and start it again while going 70mph with the heat on and stuff I think it'll give you a different estimate than if you're sitting idle at a supercharger with the heat either on low or off completely (say you just jumped into the car and was pulling out).
I feel like there is starting to be enough Tesla's on the road, and they have such a deeply powerful connectivity, that they should crowd source energy usage until they can build a really detailed model.
They could look for cars within 50 miles radius of you and look at the power draw over their last five miles and their average speed, outside temp, and climate temp setting. Then feed that data into a model and spit out your estimate. They could expand to cars within 100 miles radius and maybe in the last 30 minutes or something and just add an uncertainty factor to it to increase required energy by 5% or something to account for conditions might have changed a little.
This would go a long way to accurately measure energy usage at different temperatures based on what other users have the HVAC set to, (I suspect the large majority are in a somewhat small range of like 64 to 70F or something) and could account for weather such as snow on the road or heavy rain and standing water. They also need to pull wind data into the model and adjust for that.
Finally Tesla knows exactly how much energy the motor uses on flat land at a steady speed and they should allow you to have an advanced menu when mapping a route where you have options for like -5mph, +5mph, or +10mph offset from the posted speed limit.
Once Tesla gathered a bunch of data and created a model they probably could use their neural net to pull basic weather data from their servers (average temperate along the route from maybe 3 points [origin, 50% mark, destination] wind data, and rain or snow predicted) and then add that to their topographic data and return the estimated energy needed to the navigation. I think it would also be very useful if the car customized a profile (on their servers) for you based on your history of outside temperature and HVAC settings. Then they could predict if the outside is 25F your specific car is likely to have the setting at 72F without heated seats on (and they should have somewhat reliable data on energy usage to maintain that temperature) or if it's 30F out you tend to set it to 65F but blast the heated seat, etc. Most people I suspect have a pattern that they fall into after one or two seasons with the car. All of these things could get their predictive model to be extremely accurate.
Sure this is WAY above what every other car company does and is even beyond what A Better Route Planner does... but Tesla and especially SpaceX loves big data. They're landing rockets back on their pad while factoring in burn rate, mass of rocket, wind speeds, etc. Once a couple programmers were put to task on this I know they could have a fantastic model and data set that basically would run and manage it's self.
You might even be able to use it as a sales tool if online you could say put in your zip code and it would give you "estimated winter range, estimated snowy winter range, etc" and then recommend for you in your location to get the Long Range Model instead or something.
I did forget that for a moment that your idea also depended on all of the vehicles of this charging fleet being electric trucks, of which none are available in the market yet. Another difficulty. Oh, that's right, yet another tiny side business people expect Tesla to take on.
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