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What will be the EPA rating for the 135KWh R1T?

EPA range expectations


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Babbuino

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Lots of different info from Rivian about the actual range and that the 300+ is only for the 21in wheels... what do you guys estimate the EPA range will be for Rivian and the 135KWH pack?
If we go by the original statements, then the R1S should get 10 extra miles.
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DucRider

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Worth noting that the pack is no longer 135 kWh, but smaller than that to some unknown degree.
The 21s will definitely hit 300+. The others?
Depends on how much smaller the had to make it to "fit" (size? cost? both?) and still get "300+"
 
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Babbuino

Babbuino

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Worth noting that the pack is no longer 135 kWh, but smaller than that to some unknown degree.
The 21s will definitely hit 300+. The others?
Depends on how much smaller the had to make it to "fit" (size? cost? both?) and still get "300+"
I saw that too, just trying to differentiate between the "180" and the "135"
I'm also asking since the unofficial EPA ratings from the mach-e were much lower than expected, so I'm curious how many people trust this early statements from companies. Or if they trust the EPA ratings will be close to the initial numbers.
I think Polestar also had lower EPA rated vehicle [ 250 vs 233]
 

jjwolf120

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'm also asking since the unofficial EPA ratings from the mach-e were much lower than expected, so I'm curious how many people trust this early statements from companies. Or if they trust the EPA ratings will be close to the initial numbers.
It depends on how good their estimates were. We've also heard that the large(135?) pack has done better than expected in their range tests. Also, some cars do better than their EPA rating (Porsche Taycon) and some cars do worse than their EPA rating (most others, especially at highway speeds for EVs).
 

electruck

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I saw that too, just trying to differentiate between the "180" and the "135"
I'm also asking since the unofficial EPA ratings from the mach-e were much lower than expected, so I'm curious how many people trust this early statements from companies. Or if they trust the EPA ratings will be close to the initial numbers.
I think Polestar also had lower EPA rated vehicle [ 250 vs 233]
The only thing I trust at this point is that I can still cancel if I'm not happy with the range they actually deliver.
 

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DucRider

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I saw that too, just trying to differentiate between the "180" and the "135"
I'm also asking since the unofficial EPA ratings from the mach-e were much lower than expected, so I'm curious how many people trust this early statements from companies. Or if they trust the EPA ratings will be close to the initial numbers.
I think Polestar also had lower EPA rated vehicle [ 250 vs 233]
Might as well transition to the "Large" and "Max" terminology..
Lots of variables here, including which test the manufacturers are designing to.

The Taycan was apparently designed a bit toward WLTP where it does well, and beating the EPA number is quite easy to do in real world driving.

Recent Tesla actually score higher ranges on the EPA test than WLTP, so it is very possible many of the recent EPA range increases came not from actual increases, but optimizing for the test procedures

The Bolt EV was touted at 200+ and came in 19% higher at 238.

I have near zero doubts that the R1T will come in with at least one version with at least 300 miles on the EPA tests.
I personally think the pack is getting smaller in part not to exceed 300 by too much. If we're picking EPA roulette, I'll put my chip on 312 for the baseline version (likely the 21s).
 

jjwolf120

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The Taycan was apparently designed a bit toward WLTP where it does well, and beating the EPA number is quite easy to do in real world driving.
The interesting thing about the Taycan is that it beat the EPA at 70mph.
 

DucRider

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The interesting thing about the Taycan is that it beat the EPA at 70mph.
Possibly in part because the rear motor has a 2 speed differential that doesn't help much on the EPA hwy test, and may even hurt it (48 mph avg speed).
 

ajdelange

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Note that the 135 kWh truck is no longer the 135 kWh truck but the 300+ mile truck. Therefore I think we can be pretty certain that the EPA range will be 300+ miles. I am quite sure that Rivian is, at this point in the vehicles' development, quite confident that they can deliver 300+ miles. In fact they are probably confident that the "+" represents a pretty hefty margin (as one project manager put it "Every damn engineer on the program has a half dB in his back pocket"). This is supported by rumors that the trucks did "better than expected" in the range department during the Belle rally (or what ever it was called). In any case, once they have the design they intend to deliver ironed out they will build some and put them on a dynamometer to see how they will do against the EPA test protocol. If these tests show they can't make 300 + miles there will be a production delay as they tweak the design until they can. If they do top 300 by a considerable amount then there will be many meetings to determine how much of that margin to give the buyer. The available range is easily adjustable in software (note that Tesla has done this and in so doing earned themselves a couple or lawsuits because they did it after delivery). Engineering considerations will be traded against marketing considerations. I suppose I think a prudent decision would be to submit cars set for 304 to the EPA and deliver cars set for a wee bit more than that (306?). Thus the consumer gets a number that is bigger than 300 on the Monrony and, at least initially, finds the BMS reporting a couple of miles over that. Another strategy is to give more to the early buyers (assuming it is available) up front. This is less conservative from the engineering POV but marketing might like it better.

As to wheel size: the larger the wheel the greater its angular moment of intertia and the more energy is lost in spinning it up so I would guess that the EPA rating is going to be with the smaller wheel.
 

DucRider

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As to wheel size: the larger the wheel the greater its angular moment of intertia and the more energy is lost in spinning it up so I would guess that the EPA rating is going to be with the smaller wheel.
The twist here is that the tire fitted by Rivian on the 20 inch wheel has a larger diameter plus more "meat" than either the 21 or 22s.
Tire rack lists the Pirelli Scorpion AT (not the Rivian specific model) at 57 lbs in the 275/65R20, and the Verde AS II at 41 lbs in the 275/50R22.

Also hard to predict because often an increase in wheel diameters in paired with an increase in wheel width. Tesla keeps the same width in the front, but bumps both the wheel and tire width in the rear when moving up in wheel size.

I think the 21s will be the range king, but with only one tire option if needing replacement (at least for a while)
 

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Fenwayfan77

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As to wheel size: the larger the wheel the greater its angular moment of intertia and the more energy is lost in spinning it up so I would guess that the EPA rating is going to be with the smaller wheel.
Rivian themselves are denoting that the 21" wheels will provide the best range of the three wheel options, in that:

"Our 20" forged wheels have all-terrain tires for enhanced off-road capability. Our 21" wheels feature all-season tires for the best range. Our 22" wheels come with all-season performance tires and deliver the best on-road handling."

With that said, and in reference to your above quote, do you you believe Rivian's statement is inaccurate? If yes, that would be a bold move by them, if what you are arguing is accurate. Since you seem to be very knowledgeable in the world of engineering and mechanics, i'm not going to question your above statement, as on its face, it would appear to be an accurate and logical argument to me. I presume it would otherwise turn into a 47 page black hole discussion ;) Not going there! I'll lose. LOL.

I can only presume then, with your mechanical argument being accurate, that Rivian is obviously incorporating both Tire type (rolling resistance and other factors) AND wheel size when making the above referenced marketing claim towards mileage, as it would otherwise fly in the face of the mechanical/engineering argument you made, in that smaller wheels will have the best range, with all else being equal.

So, do you think they are going to use the smaller 20" inch wheel AND a super sneaky, more efficient tire than what they are providing as standard options to the public, in order to push the EPA ratings, since like they are claiming, their 21 inch wheel/tire combo has the better range of the two?

If they are NOT using a different, more efficient tire in the EPA test while using 20's, how can both the mechanical argument you made AND Rivian's marketing claim simultaneously stand as accurate? If 20's are more efficient overall, they would have to use a different tire in the EPA test than their planned default, already marketed tires. If not, then their claim that their 21 wheel/tire combo is misleading.

However, if they used special tires with the 20s in the EPA test, wouldn't they just shoot themselves in the foot, as the eventual, default options provided to the customer would not meet or equal their already marketed claims, in that the 21s have the better range?

I'm just going to state right now that I likely misconstrued something ;) Been a while since I had to dust off a logical reasoning argument such as that from my college philosophy classes;). Since I likely misinterpreted what you were trying to say, i'm just going to blame it on a lack of coffee ahead of time. I also have a headache. Was the juice worth the squeeze? Gonna vote no. Haha.

But, I'd like to hear your thoughts regardless.

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ajdelange

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"Our 20" forged wheels have all-terrain tires for enhanced off-road capability. Our 21" wheels feature all-season tires for the best range. Our 22" wheels come with all-season performance tires and deliver the best on-road handling."

With that said, and in reference to your above quote, do you you believe Rivian's statement is inaccurate?
No, no indeed! They know much more about what they are doing than I do. While it is true that the farther the mass is from the axle the more the rotational moment and the more the losses because of less than perfect regen there is more to it than that in terms of other things that contribute to rolling resistance, slip loss etc.


I can only presume then, with your mechanical argument being accurate, that Rivian is obviously incorporating both Tire type (rolling resistance and other factors) AND wheel size when making the above referenced marketing claim towards mileage, as it would otherwise fly in the face of the mechanical/engineering argument you made, in that smaller wheels will have the best range, with all else being equal.
Yes indeed and let me say how refreshing it is to see someone here who undersrtands some of the principles involved.


So, do you think they are going to use the smaller 20" inch wheel AND a super sneaky, more efficient tire..
Yes.





I'm just going to state right now that I likely misconstrued something.
No, don't think so.
 
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DucRider

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So, do you think they are going to use the smaller 20" inch wheel AND a super sneaky, more efficient tire than what they are providing as standard options to the public, in order to push the EPA ratings, since like they are claiming, their 21 inch wheel/tire combo has the better range of the two?
The EPA testing is required to be done with what is shipped to the public. The EPA does not test all vehicles, but do test (randomly?) some to verify the manufacturers claim.

I don't know under what circumstances it is actually required, but Tesla submits EPA applications for the different wheel size options and gets a separate Monroney for them.

The 20 inch AT tire itself is significantly heavier (much more meat and tread) plus larger in diameter than the other options.

A chat session (those do seem to have sometimes questionable accuracy) quoted in another thread said the 20s with the AT would have a significant range penalty, while the road oriented 22s would only carry a small range penalty.
 

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I'm still optimistic that the official number will be closer to 330 but I will not be surprised or disappointed if it is closer to 305. We have no charging infrastructure up here atm and my wife is giving me a hard time about $75k commuter vehicle. I make one really long trip a year (1k+ miles) but there is no charging on the route and will likely not have any for a long time. So the 300+ pack should be ok for me once the charging network is built.
 

ajdelange

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Remember that as little as 20 amperes at 240 (two outlets in a kitchen) is an 8.5 mile an hour charging "infrastructure". You as a first adopter in a remote region are going to have to be inventive but it is doable if you have an electric utility.
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