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What would you like to see on your new Rivian or from the Rivian company??

StormyKnight

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Can we have an integrated "better route planner for trailering"? I need to be able to pull a horse trailer or camper. I don't want to be stuck on the side of the road with two horses and an angry wife. Maybe start by pulling the loaded trailer for 50 miles and entering the new data on juice used/mile for accurate calculations? Integrated trailer cameras would be nice as well to check on said horses.
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ajdelange

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Can we have an integrated "better route planner for trailering"? I need to be able to pull a horse trailer or camper. I don't want to be stuck on the side of the road with two horses and an angry wife. Maybe start by pulling the loaded trailer for 50 miles and entering the new data on juice used/mile for accurate calculations?
I highlighted the last sentence because, under the assumption that Rivian's instrumentation will be at least as good as Tesla's you will have that. At the lowest level Teslas have trip odometers which display the watt hours used per mile. They also have graphs which show that over the last 5, 10 or 30 miles. After driving your Rivian for a few weeks you will have a pretty good idea as to the Wh/mi requirements for your vehicle under various conditions. For example, you will know that rain raises consumption by about 30%, that it goes up when you use the heater or drive up hill etc. If you have noted, as an example, that you have been using 500 Wh/mi in the first 10 miles heading somewhere from your place with no trailer attached but that the truck takes 1000 over the first 10 miles when heading to that same place while towing the trailer you know already that your battery is only going to take you half as far as it does without the trailer. Ratios of Wh/mi data collected over longer distances gives more reliable estimates that ratios collected over the first few miles. With collected data from trips with the trailer in tow you can put trailering Wh/mi data along with trailer wait data into the web ABRP for planning. Again assuming that Rivian will offer at least what Tesla does you will be able to put your destination into the navigation program and bring up an energy display which shows predicted battery SoC as a function of distance to the destination. At each point along the road as you drive that display predicts the remaining charge at the destination and you watch that as you go. If it drops into negative numbers you know you aren't going to make it and need to charge and about how many miles you have left. You will need to learn how to interpret this graph and I guess I should mention that based on Tesla forums there is a fair number of people who never will. An example of interpretation might be where you have crested a hill at the end of a long upgrade and the estimate at destintion is negative. If you know that a long downgrade follows you may not want to panic just yet as you will be recovering some of the range you lost.

If you currently own and use the trailer check what its effect is on your ICE vehicle's range. Does it cut it in half (not atypical)? It will do the same with your Rivian. This is why ICE trucks often come with auxiliary gas tanks sufficient to give then 600 - 800 mile range. Half of that is 300 - 400 miles. The largest Rivian will have range of 400 miles. Half of that is 200 miles. If your trailer weighs more than the truck you can expect range to be reduced by more than half and if your destination is at higher elevation than your departure point by more than that. The following estimate is really rough but were you to drive 100 miles to a place at elevation 1000' above the place from which you depart and your trailer weighs twice what the Rivian does you might expect range to be reduced to about 34% i.e. 136 miles.

Integrated trailer cameras would be nice as well to check on said horses.
There are 3rd party rear view video systems for campers and trailers. i'd think you ought to be able to mount one of those inside the trailer.
 

RayzorBEV

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I highlighted the last sentence because, under the assumption that Rivian's instrumentation will be at least as good as Tesla's you will have that. At the lowest level Teslas have trip odometers which display the watt hours used per mile. They also have graphs which show that over the last 5, 10 or 30 miles. After driving your Rivian for a few weeks you will have a pretty good idea as to the Wh/mi requirements for your vehicle under various conditions. For example, you will know that rain raises consumption by about 30%, that it goes up when you use the heater or drive up hill etc. If you have noted, as an example, that you have been using 500 Wh/mi in the first 10 miles heading somewhere from your place with no trailer attached but that the truck takes 1000 over the first 10 miles when heading to that same place while towing the trailer you know already that your battery is only going to take you half as far as it does without the trailer. Ratios of Wh/mi data collected over longer distances gives more reliable estimates that ratios collected over the first few miles. With collected data from trips with the trailer in tow you can put trailering Wh/mi data along with trailer wait data into the web ABRP for planning. Again assuming that Rivian will offer at least what Tesla does you will be able to put your destination into the navigation program and bring up an energy display which shows predicted battery SoC as a function of distance to the destination. At each point along the road as you drive that display predicts the remaining charge at the destination and you watch that as you go. If it drops into negative numbers you know you aren't going to make it and need to charge and about how many miles you have left. You will need to learn how to interpret this graph and I guess I should mention that based on Tesla forums there is a fair number of people who never will. An example of interpretation might be where you have crested a hill at the end of a long upgrade and the estimate at destintion is negative. If you know that a long downgrade follows you may not want to panic just yet as you will be recovering some of the range you lost.

If you currently own and use the trailer check what its effect is on your ICE vehicle's range. Does it cut it in half (not atypical)? It will do the same with your Rivian. This is why ICE trucks often come with auxiliary gas tanks sufficient to give then 600 - 800 mile range. Half of that is 300 - 400 miles. The largest Rivian will have range of 400 miles. Half of that is 200 miles. If your trailer weighs more than the truck you can expect range to be reduced by more than half and if your destination is at higher elevation than your departure point by more than that. The following estimate is really rough but were you to drive 100 miles to a place at elevation 1000' above the place from which you depart and your trailer weighs twice what the Rivian does you might expect range to be reduced to about 34% i.e. 136 miles.

There are 3rd party rear view video systems for campers and trailers. i'd think you ought to be able to mount one of those inside the trailer.
Yes to aftermarket solution. I currently use one on my enclosed trailer. Its a license plate frame mounted bluetooth back up camera. Works pretty well. As far as lost of range while trailering on ICE, my F150 ecoboost goes from 21 down to around 15mpg on a small enclosed aero trailer...
 

StormyKnight

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Right. I totally understand. When we have one horse in the trailer I average 15mpg with a 13’ Silverado. When there’s two horses in the trailer we average 13mpg. When we pull the camper we average 11mpg. If this is a wish list, I’d like to be able to select what I’m pulling and have some route suggestions come up without having to do math or change course mid-trip.

Most of the time paddle boards, mountain bikes and skis are loaded in our truck but a Rivian has to be able to safely and conveniently tow to some of our other adventures for me to purchase.
 

hola29

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I say this having a pre-order and a giant EV fan...

To date, I would not be buying any EV if towing beyond 120 miles was a requirement with any elevation climb. Boat ramp 15 miles away, trailer 2 hours out of town flat maybe, but if I was planning on trailering long distances a lot I would be thinking another option...even charging once mid-trailer if not stopping overnight sounds stressful.

Curious how trailering works real world. I know Rivian is directly addressing it but it still seems like a reach goal for EV’s as they exist now.

Can we have an integrated "better route planner for trailering"? I need to be able to pull a horse trailer or camper. I don't want to be stuck on the side of the road with two horses and an angry wife. Maybe start by pulling the loaded trailer for 50 miles and entering the new data on juice used/mile for accurate calculations? Integrated trailer cameras would be nice as well to check on said horses.
 

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ajdelange

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Right. I totally understand. When we have one horse in the trailer I average 15mpg with a 13’ Silverado. When there’s two horses in the trailer we average 13mpg. When we pull the camper we average 11mpg. If this is a wish list, I’d like to be able to select what I’m pulling and have some route suggestions come up without having to do math or change course mid-trip.
That's a tall order. As your experience has shown you adding the weight of one horse makes quite a bit of difference in your fuel consumption. Obviously adding a horse does not change drag but changes the mass of the trailer so that the stored energy effects (as there is no regen in a ICE truck added potential and kinetic energy are lost unless you can coast to a stop). I don't see ABRP adding a field for number of horses nor number of bicycles on board but you can tell it how much extra weight you are pulling. Even so the way ABRP processes that is only going to crudely model the effect you will encounter. For the moment you will have to do some math (or use planning software). After operating the truck for a year or so you will have learned what the second horse costs in Wh/mi and have devloped mental tricks for figuring out what you various loads imply in various weathers and terrains. You will become reliant on and trusting of the energy gauges/displays. It becomes second nature just as it is with you Silvero now. It's the same physics with a BEV as an ICE vehicle. The differences are that the fuel tanks are smaller and that the fuel pumps are slower.

The following chart may help give you some perspective on what to expect but it won't give accurate predictions by any means:

Rivian R1T R1S What would you like to see on your new Rivian or from the Rivian company?? R1TTrailerFactors
 

ajdelange

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To date, I would not be buying any EV if towing beyond 120 miles was a requirement with any elevation climb.
That seems reasonable to me. The practical nominal range of a 400 mi EPA truck is 320 miles. According to the chart in the the post that precedes this one you ought to be able to tow a 9,000 - 10,000 pound trailer about 120 miles on level terrain. But that chart is intended to be representative at best.

Boat ramp 15 miles away, trailer 2 hours out of town flat maybe, but if I was planning on trailering long distances a lot I would be thinking another option...even charging once mid-trailer if not stopping overnight sounds stressful.
Stopping for charging is not stressful at all but if you had to unhook and hook it might be.

Curious how trailering works real world.
As I keep saying it's the same as with ICE vehicles.

I know Rivian is directly addressing it but it still seems like a reach goal for EV’s as they exist now.
The thing to look at is the range of the vehicle when not towing as towing is going to cut range down to 25% of that some of the time. The EPA range of a Tesla Model X is a bit over 300 miles. With the R1T its going to be a little over 400. With the Cybertruck its going to be a little over 500. Compare to an ICE diesel with an auxiliary tank.
 

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The differences are that the fuel tanks are smaller and that the fuel pumps are slower.
The fuel pumps are also fewer and farther between, at least for the time being.

I agree with everything you said about how you develop an informed intuition over time about what you can do with your BEV range-wise. However, I fear that for someone who really needs to tow large loads over long distances frequently, an electric pickup is not the best option quite yet. The day will come, but it's a few years off.

I've owned an EV for almost five years and will never be without one again. But I still am not yet willing to let go of an ICE vehicle for lengthy trips. My brother is almost obsessed with EVs and has a Tesla Model 3 which he likes far better than any other car he's ever owned. But after twice driving it down from Atlanta to Naples, Fl -- along a leg of I-75 amply equipped with Tesla Superchargers -- he now either flies or drives down in his Honda Accord. He just found the added delays of charging too burdensome. He never gets into the Honda for trips around greater Atlanta . . . but he no longer takes the Tesla on long road trips, either. It can be done, but there is still a lot of worry about whether to skip a Supercharger that the route mapper says can be skipped. What if you hit bad weather, or a prolonged traffic tie-up, or a surprise detour, or the next charging station is out of service?
 

ajdelange

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The fuel pumps are also fewer and farther between, at least for the time being.
'Struth
However, I fear that for someone who really needs to tow large loads over long distances frequently, an electric pickup is not the best option quite yet. The day will come, but it's a few years off.
It's pretty clear that what is needed for successful towing of large loads over practical distances is a bigger on-board energy store. In an ICE vehicle, that's an auxiliary fuel tank that, for example, doubles the range of the vehicle adding only a few percent weight. In a BEV doubling the battery size means a substantial increase in weight such that range is not doubled. With batteries at their current levels of specific energy there are diminishing returns so that I question if tractor size BEV's will ever be more than experimental. It is in this segment that I think hydrogen may emerge - most probably in commercial applications but possibly for the fifth wheel recreation people.

He just found the added delays of charging too burdensome.
I have not, since owning the X found charging to be burdensome at all. If I were the hard charging young businessman with a dozen remote appointments per week I might feel differently.


It can be done, but there is still a lot of worry about whether to skip a Supercharger that the route mapper says can be skipped.
I do this as a matter of course - jump in the car and go and let the energy graph tell me when I need to charge. Now mind you I know what's out there so that...

...if you hit bad weather, or a prolonged traffic tie-up, or a surprise detour, or the next charging station is out of service?
you just stop at the closest convenient charging spot, Tesla or other, and take on more charge. This has never happened to me and as the backups are so plentiful never experience anxiety in this regard though my spouse does. I have run out of gasoline, though. I just found out that the backup CHAdeMO's around where I summer sell a kWh for less than Tesla![/QUOTE]
 

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I might have added this prior, but probably deserves a single post callout IMO - the bike mounting on SUVs could certainly use a revolutionary approach. On top of SUV's is a hassle especially for less strong/tall folks (of either gender)...Hitch mounts are a PITA opening the tailgate and they stick out way too far.

Would love to see Rivian come up with an innovative attachment point that is superior to the existing solutions. The best, as far as I am concerned, is currently mouted on spare tires - does not extend length when no in use and does not impede opening tailgate. But how many cars/trucks have rear mounted spares...not many

I have a few brainstorm ideas for them...
 
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Something to consider is that if your ICE vehicle gets half the mileage when towing, an EV will be even less. The reason is that the internal combustion engine always uses a certain amount of power just to sustain the running of the engine. Let’s say that Is 1 gallon an hour, and in cruise at 60 mph you are using 3 gph total, or 2 gph to actually move the truck. If you get half the gas mileage when towing that means you are using 6 gph or 5 gph to move the truck and trailer. You went from 2 to 5 which is a 150% increase, so the EV would see a 150% increase in power consumption for the same conditions and not just a 100% increase.
 

ajdelange

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You are not, evidently, familiar with the concept of efficiency. If it takes X watts to move the truck the energy store must supply more than X because the device that converts stored energy to motive energy is not capable of converting all it is given into motive energy. A penalty must be paid either to M. Carnot (ICE) or as a much smaller penalty to resistive heating in an BEV. Thus it takes some number r > 1 times X to move the truck. Now in an ICE vehicle r has value 4 to 5. With an electric vehicle its much smaller, perhaps 1.25 or so. But it doesn't matter. If you double X the energy source requirement increases from r*X to 2*r*X and as the fuel store is fixed range drops in half. It clearly doesn't matter what r is.

1/r is called "efficiency". An ice vehicle with r = 5 is said to have an efficiency of 0.2 usually written as 20%. Only 20% of the energy stored in gasoline or diesel is convertible to motive energy. A BEV with r = 1.25 has an efficiency of 0.8 (usually expressed as 80%). Eighty percent of the battery's energy gets converted to motive energy,

If your ICE vehicle's towing range drops in half when attaching a trailer attaching that same trailer to a BEV may result in a range reduction of more or less than half. Carnot waste has nothing to do with it as discussed above. There is fixed waste "just to sustain the running of the engine" in an electric motor too. It's just smaller.
 

CappyJax

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You are not, evidently, familiar with the concept of efficiency. If it takes X watts to move the truck the energy store must supply more than X because the device that converts stored energy to motive energy is not capable of converting all it is given into motive energy. A penalty must be paid either to M. Carnot (ICE) or as a much smaller penalty to resistive heating in an BEV. Thus it takes some number r > 1 times X to move the truck. Now in an ICE vehicle r has value 4 to 5. With an electric vehicle its much smaller, perhaps 1.25 or so. But it doesn't matter. If you double X the energy source requirement increases from r*X to 2*r*X and as the fuel store is fixed range drops in half. It clearly doesn't matter what r is.

1/r is called "efficiency". An ice vehicle with r = 5 is said to have an efficiency of 0.2 usually written as 20%. Only 20% of the energy stored in gasoline or diesel is convertible to motive energy. A BEV with r = 1.25 has an efficiency of 0.8 (usually expressed as 80%). Eighty percent of the battery's energy gets converted to motive energy,

If your ICE vehicle's towing range drops in half when attaching a trailer attaching that same trailer to a BEV may result in a range reduction of more or less than half. Carnot waste has nothing to do with it as discussed above. There is fixed waste "just to sustain the running of the engine" in an electric motor too. It's just smaller.
I'll walk you through it.

What is the efficiency of an ICE at idle while not moving the vehicle? Is it the 20% you claim, or perhaps some lower number?
 

hola29

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I'll walk you through it.

What is the efficiency of an ICE at idle while not moving the vehicle? Is it the 20% you claim, or perhaps some lower number?
this thread will quickly go down the rabbit hole if you two take this to the mat, lol.
 

CappyJax

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this thread will quickly go down the rabbit hole if you two take this to the mat, lol.
I am merely trying to educate someone with some academic knowledge of the topic to understand the practical application of that knowledge.
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