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TessP100D

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You all are fishing for an answer you won’t get. It appears people want Rivian to some how fess up to a number larger than 50%.

That 50% is likely worst case because if you overlay the power curves of an electric motor and an ice engine, they don’t match at high torque. ICE motors lose efficiency at the top end where electric motors are most efficient. This is why in the efficiency mode, you get more range. Two motors under double the torque are more efficient.

That said, the argument that energy is energy is absolutely true. I say this as an a mechanical engineer. Drag and rolling resistance are the biggest factor, by a lot. Motor efficiency is peanuts…and ICE vehicles don’t regen. I know everyone on here is excited, but this is literally just like refilling a gas vehicle except it takes more and longer fill ups to do it. That’s ok for some and not for others. If you’re the type that gets anxiety over a low battery, being an early adopter may not be a great choice.
I agree with your statements. However. I’m not convinced till I see the real numbers. Not some percentage guesstimate by Rivian.
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Temerarius

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I agree with your statements. However. I’m not convinced till I see the real numbers. Not some percentage guesstimate by Rivian.
Like what?

A break down by weight of your trailer, the drag coefficient, the % grade you will go up, the temperatures outside, current weather conditions, how many axels you have on the trailer, how well lubricated those bearings are on your trailer, and how heavy of a foot you have...?

Seriously... people getting wrapped around the axel of towing and asking "Will I get 234 miles, or 229 miles?!!?!" is how this thread is coming off.

"You will not get your max range while towing... anything."

You will never get this answered there are FAR too many variables involved (and do you ask this question when buying an ICE truck? No... because the answer is the same... "Your range will be less per fill up based on a billion different factors.")

This question is about the stupidest one I've seen that is constantly floating up. People seem to expect Rivian to vomit up a 3,000 page document listing the range based on every single factor that impacts range "While the truck is towing."

At best, you will get rough guestimates based on weight and maybe a generalization of the trailer form-factor... and they will be just that, guestimates.

Or you can relax the fuck out and realize that your range will be less while towing, that you will probably need to budget an extra amount of time to charge up on a longer trip versus an ICE truck.
 
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GooniesNeverSayDie

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Like what?

A break down by weight of your trailer, the drag coefficient, the % grade you will go up, the temperatures outside, current weather conditions, how many axels you have on the trailer, how well lubricated those bearings are on your trailer, and how heavy of a foot you have...?

Seriously... people getting wrapped around the axel of towing and asking "Will I get 234 mile, or 229 miles?!!?!" is how this thread is coming off.

"You will not get your max range while towing... anything."

You will never get this answered there are FAR too many variables involved (and do you ask this question when buying an ICE truck? No... because the answer is the same... "Your range will be less per fill up based on a billion different factors.")

This question is about the stupidest one I've seen that is constantly floating up. People seem to expect Rivian to vomit up a 3,00 page document listing the range based on every single factor that impacts range "While the truck is towing."

At best, you will get rough guestimates based on weight and maybe a generalization of the trailer form-factor... and they will be just that, guestimates.

Or you can relax the fuck out and realize that your range will be less while towing, that you will probably need to budget an extra amount of time to charge up on a longer trip versus an ICE truck.

It seems to me that asking range questions is fair game. Real world numbers can obviously differ greatly from the info the mfg puts out. Everyone understands you will get less range while towing but understanding how much less based on real world examples is very helpful to those considering purchasing a 80K truck. Obviously, that information isn't available right now since no one has their trucks but it should be soon.
 

Temerarius

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It seems to me that asking range questions is fair game. Real world numbers can obviously differ greatly from the info the mfg puts out. Everyone understands you will get less range while towing but understanding how much less based on real world examples is very helpful to those considering purchasing a 80K truck. Obviously, that information isn't available right now since no one has their trucks but it should be soon.
I guess here is the key question: "How much information is needed from the manufacturer to answer this question?"

They have already fired off an estimate that an 11,000lbs trailer will drop you by "around 50%".

Do they need to break that down by "Shape of trailer"? Do they need to break that down by "Every 1,000 pounds"?

I get that people that tow are curious, so am I, but, given my experiences towing with my diesel, I have a rough idea on what to expect when it comes to the hit on range.

My boat comes in at around 4,600-5,000 pounds depending on what all I have on it and such. It crushes my diesel (3L EcoDiesel running Banks), dropping it from 28MPG to around 11MPG on the flat (moving my range from 742 "optimal" miles of range down to 291 "optimal" miles of range).

However, that does not account for winds, elevation changes, stop and go traffic, a lead foot, or anything else that may impact that.

Did Ram tell me any of that? No.

I'm not quite sure why folks expect Rivian to cover this in any more detail than what they have.

Now, if they get crazy with it and build in a "tow estimator" like Ford is putting in theirs that can use scales and a "generalized" trailer form factor to give you a rough idea when towing, and then update once you are a few miles in... THAT I would find more useful than some guess in a document.
 
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Eager2own

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First part of your reply says "that premise is wrong" then in your very next sentence you state "I acknowledge that your premise is correct"
Yes, my next sentence was that I agree with part of your premise before then explaining the part of it I didn't agree with -- I don't agree with the conclusion that, if a trailer impacts range in one vehicle by 50%, it must impact another by the same 50% (with only a negligible difference).


If the load we're talking about here makes an ICE vehicle lose roughly half its range, then it will also make an equivalent size/weight EV lose roughly half its range.
I do not agree that pulling, for example, a sled with 1000 lbs of sand behind a high torque diesel engine will impact the range to the same extent than towing that same sled behind ... my Miata. The high torque engine's advantage to tow the same load at low rpms will result in less range impact. Again, I agree that the energy/force needed to pull the sled is the same in both scenarios, but NOT that the impact to range is same for both vehicles.
I may be wrong, but I'm willing to bet a six-pack that range impact will be much greater for my Miata.

Have I got news for you... Electric motors without transmission losses are more efficient than the above!
Not news to me. I never said the BEV would do worse than the ICE. All I was saying is I wouldn't assume that the range impact on a Rivian would be the same as to an ICE vehicle anymore than I would buy a Miata expecting it to have only the same range impact as a Hemi truck when pulling the same trailer.
I wasn't passing judgment on the Rivian, or complaining that it's worse than an ICE. In fact, just to clarify because of how my statement was characterized by another, I am in no way saying that Rivian hasn't provided enough information or complaining that they must provide more to cover every scenario. As others indicated, I think Rivian already has done more than I've seen from other OEMs. I was merely pointing out I don't think range impact is same for all vehicles.
 

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Driveout

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The obvious solution is to make a trailer with an integral battery in the floor. Tow 1000 miles if you like then. Of course there might be a slight weight penalty decreasing the available volume of the towed trailer. Forget the slideouts, give me an inflatable like the Bigelow for the ISS and make it like an aerodynamic tent trailer on steroids that opens like a clamshell. Drag coefficient should be pretty good. It would probably void the warranty on the onboard compressor though...
 

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Yes, my next sentence was that I agree with part of your premise before then explaining the part of it I didn't agree with -- I don't agree with the conclusion that, if a trailer impacts range in one vehicle by 50%, it must impact another by the same 50% (with only a negligible difference).
It's been said repeatedly ROUGHLY 50%.

It's been explicitly said (including by a mechanical engineer) that powertrain loses are a small amount of the overall cost in carrying a heavy load.

Also, as is evidenced below, you're making an extremely disingenuous argument by comparing completely unalike vehicles

I do not agree that pulling, for example, a sled with 1000 lbs of sand behind a high torque diesel engine will impact the range to the same extent than towing that same sled behind ... my Miata. The high torque engine's advantage to tow the same load at low rpms will result in less range impact. Again, I agree that the energy/force needed to pull the sled is the same in both scenarios, but NOT that the impact to range is same for both vehicles.
I may be wrong, but I'm willing to bet a six-pack that range impact will be much greater for my Miata.
So, for example, comparing a 2,200lb Miata to a 6,900lb F-250 with 6.7L diesel...

If you compare a Miata that wasn't designed to tow anything, has a powertrain tuned for high rev responsiveness, and is being asked to tow half its own weight...

To a truck designed to tow over twice it's own 6,900lb weight, with a powertrain designed for that, and is being asked to tow what could fit as payload in the back...

Then yes, the Miata will lose more range proportionally.

But if you can't spot the reasons why this isn't remotely relevant, then I'll go ahead and stop engaging.

Not news to me. I never said the BEV would do worse than the ICE. All I was saying is I wouldn't assume that the range impact on a Rivian would be the same as to an ICE vehicle anymore than I would buy a Miata expecting it to have only the same range impact as a Hemi truck when pulling the same trailer.
When comparing remotely similar vehicles (e.g. 7,000lb trucks designed to tow 5-digit poundage), the powertrain differences will be *EXTREMELY* small compared to the absolute, physically required energy cost of towing that load.

There's no reasonable counterexample you can come up with that will show otherwise because it's physics.
 

CharonPDX

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No it’s not.

range is the absolute most important thing to a EV.

so when a simp,e thing like towing effects that range so dramatically it will be important to know that real world results of that range loss.

we’re on the same side. I juts want to know the facts ASAP.
"A simple thing like towing" impacts ICE vehicles, too. My 1996 Ford F-250 diesel gets 20-25 MPG driving empty. When towing my ~6000 pound travel trailer, I get 10-12 MPG.

Range is *NOT* the absolute most important thing to an EV. I have three EVs now, and range is only important on one of them. All the other aspects of the vehicle are important to me on the other two.

Hell, even on the Rivian, range won't be the most important thing - the ability to tow my trailers. It doesn't matter what range it has (Tesla Model X) if it can't tow my trailer. Sure, Model X can do 340 miles on a charge - but it can't tow my trailer. So those 340 miles don't matter. (And my existing Model S definitely can't do it.) Sure, the Lucid Air may be able to do 520 miles on a charge - but it can't tow at all, so that range is pointless.

As for real-world - there are tons of data points of existing EV owners towing (mostly Tesla Model X) and seeing a 50% range drop at full load, exactly as Rivian is predicting.

You're being argumentative and negative - being presented with the facts that are available, and completely dismissing them, exactly as SANZC02 predicted.
 

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The only question this thing has me asking is what about tow mirrors?
 

Eager2own

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It's been said repeatedly ROUGHLY 50%.

It's been explicitly said (including by a mechanical engineer) that powertrain loses are a small amount of the overall cost in carrying a heavy load.

Also, as is evidenced below, you're making an extremely disingenuous argument by comparing completely unalike vehicles



So, for example, comparing a 2,200lb Miata to a 6,900lb F-250 with 6.7L diesel...

If you compare a Miata that wasn't designed to tow anything, has a powertrain tuned for high rev responsiveness, and is being asked to tow half its own weight...

To a truck designed to tow over twice it's own 6,900lb weight, with a powertrain designed for that, and is being asked to tow what could fit as payload in the back...

Then yes, the Miata will lose more range proportionally.

But if you can't spot the reasons why this isn't remotely relevant, then I'll go ahead and stop engaging.



When comparing remotely similar vehicles (e.g. 7,000lb trucks designed to tow 5-digit poundage), the powertrain differences will be *EXTREMELY* small compared to the absolute, physically required energy cost of towing that load.

There's no reasonable counterexample you can come up with that will show otherwise because it's physics.
My simple point all along is that just saying that “energy is energy” and concluding that impact of the load will be the same on all vehicles regardless of drivetrain is not accurate.
I did use an extreme example to show why that isn’t always the case despite the load and energy required being the same for a Miata and a truck. Your response that they are designed for different purposes doesn’t answer why “physics” don’t apply. If you have two equal trucks, except one has a 2.0L 4-cylinder and one has a large Diesel engine, the impact on range will be different if they tow the same trailer around and the diesel can do it with slightly higher rpms while the 4-cylinder is screaming at high rpms around town because of the much lower torque.
Again, my point is that if we can’t say inmpact is the same as to between all ICE vehicles, how can we make the even broader statement that impact to range for a BEV would the same as to any ICE vehicle?
 

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If you have two equal trucks, except one has a 2.0L 4-cylinder and one has a large Diesel engine, the impact on range will be different if they tow the same trailer around and the diesel can do it with slightly higher rpms while the 4-cylinder is screaming at high rpms around town because of the much lower torque.
These are not equal trucks because their rated capabilities are not remotely in the same ballpark.

My simple point all along is that just saying that “energy is energy” and concluding that impact of the load will be the same on all vehicles regardless of drivetrain is not accurate.
I did use an extreme example to show why that isn’t always the case despite the load and energy required being the same for a Miata and a truck. Your response that they are designed for different purposes doesn’t answer why “physics” don’t apply.

I think people here (including myself) that are pushing back against your arguments have made a shared assumption that you don't actually share.

Two vehicles of roughly the same size, weight, and towing capability can have drastically different powertrains but the range loss for towing a given load will be roughly equivalent.

This is why it's been explicitly stated that we're comparing the 7,000lb Rivian with a 7,000lb ICE truck that can also tow 11,000lbs

I mean, look...
If a 7,000 ICE truck towed 11,000 pounds behind it and its range was cut roughly in half...

...Then the 7,000 R1T towing 11,000 pounds behind it will have its range cut roughly in half.
Since there's absolutely nobody in the entire world who is cross shopping a Miata or a normally aspirated 2.0l 4-cyl pickup with an R1T... We probably figured this goes without saying.
 

Eager2own

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Folks who are tired of our back-and-forth will be happy to see that we’ve come full circle and found some common ground.
Now that you limit it to similar towing capabilities (in other words, generally same torque/power), you’re essentially just repeating what I said in my very first post.

However, the assumption that the additional load will impact range on both vehicles equally is incorrect. That’s not even true for ICE vehicles. The impact of that additional load on an F150 with a 4-cylinder engine is not the same as it would have on an F150 with a V8 or a Diesel engine.
We seem to agree it’s not enough to say “energy is energy” as if the same load will affect all 7,000 lb trucks equally. My pushback has been to that idea that physics dictates that, because energy to pull with each vehicle is the same, impact to range is the same. It does matter that power plants and drivetrains have similar performance.
And if that’s the case, the results are roughly similar — on that we can agree.
 

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If long distance towing is a primary concern, an EV is likely not the best choice...short distances, like 75-100 miles sure great fit, but anything past that and 11K pounds, a diesel sounds like away better option...Powered trailers may change that, or battery tech, but right now, if long distance towing of 7500lb+ 100 miles or more, I would not be buying a Rivian...
 

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Now if someone would just develop a trailer system for extending the battery pack of the attached vehicle (regardless of manufacturer) you could in theory bypass the car/truck's battery pack and deplete the trailers supplemental battery pack. This way when you get to your destination the car/truck is partially or fully charged and you leave the trailer (camp site, boat launch, etc) and have a vehicle for errands or excursion trips.
 

TessP100D

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"A simple thing like towing" impacts ICE vehicles, too. My 1996 Ford F-250 diesel gets 20-25 MPG driving empty. When towing my ~6000 pound travel trailer, I get 10-12 MPG.

Range is *NOT* the absolute most important thing to an EV. I have three EVs now, and range is only important on one of them. All the other aspects of the vehicle are important to me on the other two.

Hell, even on the Rivian, range won't be the most important thing - the ability to tow my trailers. It doesn't matter what range it has (Tesla Model X) if it can't tow my trailer. Sure, Model X can do 340 miles on a charge - but it can't tow my trailer. So those 340 miles don't matter. (And my existing Model S definitely can't do it.) Sure, the Lucid Air may be able to do 520 miles on a charge - but it can't tow at all, so that range is pointless.

As for real-world - there are tons of data points of existing EV owners towing (mostly Tesla Model X) and seeing a 50% range drop at full load, exactly as Rivian is predicting.

You're being argumentative and negative - being presented with the facts that are available, and completely dismissing them, exactly as SANZC02 predicted.
I’m looking for a real number. not some guess By a manufacture and repeated as fact by first adopters.
‘’look is simple.
on a straight line with no elevation change and no head winds, what bus the range loss?


when the truck actually gets shipped the we will know. not before hand.
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