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Budman

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I've been a R1T owner for about 2.5 years now. First a Gen 1 Quad Motor Large Battery which I recently traded in for a Gen 2 Dual Motor Max Pack. Combined, I have about 60,000 miles on the two vehicles. I'm a bit of a data geek (35 years experience as a Mechancal Design and Test Engineer), I've collect detailed data on my road trip efficiency, range, and charging performance.

What follows is a detailed summary of the data I collected which I offer to you as another reference source to compliment the observations given by some popular YouTube Influencers. I often find those YouTube videos to be superficial despite their length, lacking statistical rigor and proper context, and sometimes just plain wrong.

KEY POINTS TO BE MADE BELOW:
Gen 2 and Gen 1 have similar efficiencies.
Heat pump not yet seen to provide a benefit
Overall range figures meet EPA estimates when driven on a mix of city/rural/highway route.
Gen 2 and Gen 1 have similar fast charging performance.
The most optimal road trip charging strategy is to stop for around 20 to 25 minutes and add around 60 kWh of energy.
It is not necessary to start a charging session at very low states of charge (like 10%) to have a fast road trip. Starting around 20% will yield roughly the same overall time with much less risk.


DETAILED ANALYSIS

Efficiency and Range:

I drive the same 165 mile route frequently. It's a mix of 70mph Freeway and 55mph rural roads with frequent slower sections through intersections and small towns. I think it is close-ish to the EPA combined city/highway test cycle. As such, I have observed my R1Ts have closely matched the EPA stated values for range.

I've posted versions of this next chart many times on this forum. However, this time I have enough data on the Gen 2 Dual Motor Max pack to start making statistically meaningful comparisons. The shaded areas are the 95% confidence intervals on the calculated mean line fit.

Points to Make:
The Gen 2 Dual Motor Max Pack (22" wheels) has very similar efficiency vs temperature performance as the Gen 1 Quad Motor Large Battery (21" wheels) when in Conserve Mode.

I've not yet observed any meaningful efficiency benefit from the heat pump in the Gen 2 vehicle. Sample size is still a bit small, perhaps a benefit will emerge over time.

For the Gen 1 Quad, in warmer temperatures, at the speeds I travel on this route, there is a significant improvement in efficiency in conserve vs all. purpose.

*** This is not a 75 mph highway speed efficiency test. I am not claiming I see this efficiency at higher speeds for extended periods. ****
Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis R1T efficiency vs tem



The calculated full pack range I would see based on these efficiency numbers is shown below;

Points to Make:
Assuming a 131 kWh battery pack for the Gen 1 Quad vehicle. A 141 kWh battery pack for the Gen 2 max pack.

As noted above. My observed range is inline with the EPA test (420 miles for Gen 2 Max Pack).

At around 70 deg F, the range increase in the Gen 2 to Gen 1 is inline with expectations given the 10 kWh larger battery (10 kWh * 3 m/kWh = 30 miles more range)

*** This is not a 75 mph highway speed range test. I am not claiming I see this range at higher speeds for extended periods. ****
Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis R1T range vs tem




Charging Analysis:
I've used Electrify America charges a lot on several long road trips with my Gen 1 Large Pack vehicle. The EA app history provides info on total charging time and energy delivered. I've only done a few charging sessions with the Gen 2 Max pack but I wanted to present these results as it is this topic where I the biggest difference of opinion compared to some of the recent YouTube video on the Gen 2 Max Pack charging behavior.

First chart: The chart below shows the total energy delivered during a charging session on the horizontal axis and the time spend charging on the vertical axis.

Points to Make:
To a first order estimate, the Gen 1 Large pack and Gen 2 Max pack appear to have very similar charging performance when comparing multiple charging sessions of each and taking into account the inevitable variability the occurs when charging an electric vehicle.

As most of us are aware, charging performance follows an exponential function. Adding more and more energy takes longer and longer as the battery gets more fully charged. I used an exponential line fit algorithm to create the solid lines seen on the chart.

One of the data points shown I took from the "10% challenge" video recently posted that was the subject of particular ire from the YouTube influencer.

I don't want to linger too long on this chart because there are some other variables at play that are very important that must be taken into account. These following charts do this.
Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis Charge Time G1 vs G2



Charging performance is very dependent on the starting state of charge (denoted SOC on the charts). A low initial SOC will charge faster than a high initial SOC. Fortunately, the EA app history shows the starting and ending SOC for each session. The Tesla app does not do this so I can't do a similar exercise for the supercharger data.

In the next chart I created separate data sets to fit the exponential line to based on the initial states of charge. The data bins are; 10% to 20% initial SOC, 21% to 30% initial SOC, 31% to 40% initial SOC, etc.

Points to Make:
This chart only shows Gen1 Large Pack data (Gen 2 added into the following chart).

You can clearly see the impact of starting a session with a battery that is relatively full (red data, >40% charged. Black data >50% SOC at start of session).

But, charging performance is not overly sensitive to initial SOC if below <30% and the energy added is <70 kWh or so. The green and blue lines are pretty close together and differ by only a couple minutes of charging time. It does not really matter much too much if the battery is say 15% full or 25% full when you start, you get about the same charging performance.

Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis Charge Time by SOC



Gen1 Large Pack vs Gen 2 Max Pack Charger Performance

I've done a few charging sessions with the Gen 2 Max Pack. The sessions were at starting states of charge of <20% or between 30% and 40%. For clarity I removed the other data bins. And I added in the data from the "10% challenge" YouTube video.

Points to Make:
Gen 2 Max Pack shown in the large square markers.

When factoring in the initial states of charge of the batteries, the Gen 2 Max Pack has charged very similarly to the Gen 1 Large Pack

Over more charging sessions perhaps a difference will emerge but the difference would likely be on the order of a couple minutes or less.

*** Disclaimer: My Gen 2 Max pack sessions have been in cool to cold weather. I have not evaluated the performance in temperatures >50 Deg F ****


Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis G1 vs G2



Efficient Road Trip Charging Strategy for Rivian Vehicles

With the exponential curve fits vs SOC in hand I can do some interesting road trip simulations to evaluate different charging strategies. For the example that follows I said a traveler needs to add 300 kWh of energy on the road (about 600 to 700 miles of traveling). I looked at charging times if stopping 4, 5, 6, 7, 8 or 9 times. The required energy to be added at each stop is 300 divided by n (number of stops) which works out to 75, 60, 50, 42.5, 37.5 or 33.3 kWh per stop. For the first chart I assumed 8 minutes of overhead time per stop (getting off the highway, traversing to the charger, fiddling with apps, get back on the freeway).

Chart explanation:
Actual charging time calculated for the exponential curve fits are in the text blocks next to each data point.
The horizontal axis is number of stops and energy to be added.
Vertical axis is total charing + overhead time summed up over the n number of stops
Green line assuming a starting state of charge of <20% and the blue is starting SOC between 21% and 30%

Points to Make:
The optimal solution for Rivian vehicles is a 5 stop strategy onboarding 60 kWh with charging times between 20 and 23 minutes depending on initial battery level.

Faster overall charging time is quicker with very low battery levels but I view this as a high risk, low reward strategy. Adding 15 minutes to my is insignificant compared to the consequences pushing the envelope and running out of battery.

A wide range of solutions are within 15 minutes of the "best" solution. To me, that does not matter. Don't obsess over charging stops/battery levels etc. Charge when the battery is down around 20% or so, charge for 20 to 25 minutes an add around 60 kWh.

Eight minutes of overhead might be on the high side the the 2nd chart shows a 4 minute over head simulation.

Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis 8 min OH



4 Minutes of overhead:
Points to Make:
With less overhead a 6 stop strategy might be ever so slightly better than the 5 stop strategy.
Again, many solutions are within 10 minutes of the "best" solution. Don't obsess over it.

Speaking of obsessing... A well known YouTube Influencer seems to be very obsessed with charging speeds and strategies. The 10% challenge test with 15 minutes of charging time is held as an example of a smart road trip strategy. Strictly speaking, 15 minutes of charging time is demonstratively NOT the best solution for the Rivian vehicles. It is not significantly worse that the best and it might be the best for other vehicles but not for Rivian vehicles.

Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis 4 min OH



For completeness the chart below included how much time it would take if you initiated every charging session with a pretty full battery. It could add over an hour to your trip time.

Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis 8min OH 4 curves



Bonus chart:
Supercharger vs Electrify America; I can’t break it out by initial SOC but lumping everything together shows the Superchargers and EA to be, on average, the same for charging times.

Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis Charge Time EA vs SC


Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis 8 min OH
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QuadMonster

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Thank you! We have several road trips planned with our Gen 1, and your data will significantly help us optimize charging times. We prefer shorter, efficient stops over longer ones to minimize waiting.
 

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Thanks, this is helpful. By any chance did you compare your data to what ABRP might recommend?

Also, it's not surprising that the G2s aren't really any more efficient than the G1s. Aerodynamic drag is going to be the bigger consumer of energy at higher speeds. Honestly glad I didn't go for a G2 truck at this point.

Heat pumps can be more efficient, but given this is a first Gen for Rivian, I didn't have high hopes. Additionally, heat pumps are less efficient in hot temps than a normal AC unit and I live in Texas. So the marginal gain I might get in our very short winters would likely be offset by our long and hot summers.
 
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Budman

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Thanks, this is helpful. My any chance did you compare your data to what ABRP might recommend?

Also not surprise that the G2's aren't really any more efficient than the G1s. Aerodynamic drag is going to be the bigger consumer of energy at higher speeds. Honestly glad I didn't go for a G2 truck at this point.

Heat pumps can be more efficient, but given this is a first Gen for Rivian, I didn't have high hopes. Additionally, heat pumps are less efficient in hot temps than a normal AC unit and I live in Texas. So the marginal gain I might get in our very short winters would likely be offset by our long and hot summers.
Good question about ABRP. It does give about the same answer. 20 minutes and 50 to 60 kWh energy to add.
Rivian R1T R1S R1T Gen 1 Quad Large vs. Gen 2 Dual Max Pack: Efficiency and Charging Analysis IMG_3895
 

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My ABRP displays longer intervals and fewer stops for my routes.
I have it set for quickest arrival.
 

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I just want to take a moment to appreciate all the work @Budman did and acknowledge the joy it gave me to nerd out on his data and analysis. Especially appreciated the key findings and conclusions for people like me who might get lost in the data and lose sight of the pragmatic.

Great insights that will definitely help us on future road trips!
 

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Good stuff. I've been thinking we need something like this for driving speed vs efficiency. Driving faster can get you there quicker except it increases your charging time. Might be another variable to try to factor into your charts? A Monte Carlo or optimization function might be the way to go for that.
 

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Now this is proper testing. Great work and the huge amount of effort will be appreciated by many.

Also re: the heat pump, I suspect the minor differences are exactly the reason it wasn't in the gen 1, however most people don't work with details/reality. They just see a spec sheet and will say "Rivians don't even have a heat pump!" I'm certainly not sad that I have one and I'm sure there's a few times it will save me a percentage point or two, for whatever that's worth.
 

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I've been a R1T owner for about 2.5 years now. First a Gen 1 Quad Motor Large Battery which I recently traded in for a Gen 2 Dual Motor Max Pack. Combined, I have about 60,000 miles on the two vehicles. I'm a bit of a data geek (35 years experience as a Mechancal Design and Test Engineer), I've collect detailed data on my road trip efficiency, range, and charging performance.

What follows is a detailed summary of the data I collected which I offer to you as another reference source to compliment the observations given by some popular YouTube Influencers. I often find those YouTube videos to be superficial despite their length, lacking statistical rigor and proper context, and sometimes just plain wrong.

KEY POINTS TO BE MADE BELOW:
Gen 2 and Gen 1 have similar efficiencies.
Heat pump not yet seen to provide a benefit
Overall range figures meet EPA estimates when driven on a mix of city/rural/highway route.
Gen 2 and Gen 1 have similar fast charging performance.
The most optimal road trip charging strategy is to stop for around 20 to 25 minutes and add around 60 kWh of energy.
It is not necessary to start a charging session at very low states of charge (like 10%) to have a fast road trip. Starting around 20% will yield roughly the same overall time with much less risk.


DETAILED ANALYSIS

Efficiency and Range:

I drive the same 165 mile route frequently. It's a mix of 70mph Freeway and 55mph rural roads with frequent slower sections through intersections and small towns. I think it is close-ish to the EPA combined city/highway test cycle. As such, I have observed my R1Ts have closely matched the EPA stated values for range.

I've posted versions of this next chart many times on this forum. However, this time I have enough data on the Gen 2 Dual Motor Max pack to start making statistically meaningful comparisons. The shaded areas are the 95% confidence intervals on the calculated mean line fit.

Points to Make:
The Gen 2 Dual Motor Max Pack (22" wheels) has very similar efficiency vs temperature performance as the Gen 1 Quad Motor Large Battery (21" wheels) when in Conserve Mode.

I've not yet observed any meaningful efficiency benefit from the heat pump in the Gen 2 vehicle. Sample size is still a bit small, perhaps a benefit will emerge over time.

For the Gen 1 Quad, in warmer temperatures, at the speeds I travel on this route, there is a significant improvement in efficiency in conserve vs all. purpose.

*** This is not a 75 mph highway speed efficiency test. I am not claiming I see this efficiency at higher speeds for extended periods. ****
R1T efficiency vs temp.jpg



The calculated full pack range I would see based on these efficiency numbers is shown below;

Points to Make:
Assuming a 131 kWh battery pack for the Gen 1 Quad vehicle. A 141 kWh battery pack for the Gen 2 max pack.

As noted above. My observed range is inline with the EPA test (420 miles for Gen 2 Max Pack).

At around 70 deg F, the range increase in the Gen 2 to Gen 1 is inline with expectations given the 10 kWh larger battery (10 kWh * 3 m/kWh = 30 miles more range)

*** This is not a 75 mph highway speed range test. I am not claiming I see this range at higher speeds for extended periods. ****
R1T range vs temp.jpg




Charging Analysis:
I've used Electrify America charges a lot on several long road trips with my Gen 1 Large Pack vehicle. The EA app history provides info on total charging time and energy delivered. I've only done a few charging sessions with the Gen 2 Max pack but I wanted to present these results as it is this topic where I the biggest difference of opinion compared to some of the recent YouTube video on the Gen 2 Max Pack charging behavior.

First chart: The chart below shows the total energy delivered during a charging session on the horizontal axis and the time spend charging on the vertical axis.

Points to Make:
To a first order estimate, the Gen 1 Large pack and Gen 2 Max pack appear to have very similar charging performance when comparing multiple charging sessions of each and taking into account the inevitable variability the occurs when charging an electric vehicle.

As most of us are aware, charging performance follows an exponential function. Adding more and more energy takes longer and longer as the battery gets more fully charged. I used an exponential line fit algorithm to create the solid lines seen on the chart.

One of the data points shown I took from the "10% challenge" video recently posted that was the subject of particular ire from the YouTube influencer.

I don't want to linger too long on this chart because there are some other variables at play that are very important that must be taken into account. These following charts do this.
Charge Time G1 vs G2.jpg



Charging performance is very dependent on the starting state of charge (denoted SOC on the charts). A low initial SOC will charge faster than a high initial SOC. Fortunately, the EA app history shows the starting and ending SOC for each session. The Tesla app does not do this so I can't do a similar exercise for the supercharger data.

In the next chart I created separate data sets to fit the exponential line to based on the initial states of charge. The data bins are; 10% to 20% initial SOC, 21% to 30% initial SOC, 31% to 40% initial SOC, etc.

Points to Make:
This chart only shows Gen1 Large Pack data (Gen 2 added into the following chart).

You can clearly see the impact of starting a session with a battery that is relatively full (red data, >40% charged. Black data >50% SOC at start of session).

But, charging performance is not overly sensitive to initial SOC if below <30% and the energy added is <70 kWh or so. The green and blue lines are pretty close together and differ by only a couple minutes of charging time. It does not really matter much too much if the battery is say 15% full or 25% full when you start, you get about the same charging performance.

Charge Time by SOC.jpg



Gen1 Large Pack vs Gen 2 Max Pack Charger Performance

I've done a few charging sessions with the Gen 2 Max Pack. The sessions were at starting states of charge of <20% or between 30% and 40%. For clarity I removed the other data bins. And I added in the data from the "10% challenge" YouTube video.

Points to Make:
Gen 2 Max Pack shown in the large square markers.

When factoring in the initial states of charge of the batteries, the Gen 2 Max Pack has charged very similarly to the Gen 1 Large Pack

Over more charging sessions perhaps a difference will emerge but the difference would likely be on the order of a couple minutes or less.

*** Disclaimer: My Gen 2 Max pack sessions have been in cool to cold weather. I have not evaluated the performance in temperatures >50 Deg F ****


G1 vs G2.jpg



Efficient Road Trip Charging Strategy for Rivian Vehicles

With the exponential curve fits vs SOC in hand I can do some interesting road trip simulations to evaluate different charging strategies. For the example that follows I said a traveler needs to add 300 kWh of energy on the road (about 600 to 700 miles of traveling). I looked at charging times if stopping 4, 5, 6, 7, 8 or 9 times. The required energy to be added at each stop is 300 divided by n (number of stops) which works out to 75, 60, 50, 42.5, 37.5 or 33.3 kWh per stop. For the first chart I assumed 8 minutes of overhead time per stop (getting off the highway, traversing to the charger, fiddling with apps, get back on the freeway).

Chart explanation:
Actual charging time calculated for the exponential curve fits are in the text blocks next to each data point.
The horizontal axis is number of stops and energy to be added.
Vertical axis is total charing + overhead time summed up over the n number of stops
Green line assuming a starting state of charge of <20% and the blue is starting SOC between 21% and 30%

Points to Make:
The optimal solution for Rivian vehicles is a 5 stop strategy onboarding 60 kWh with charging times between 20 and 23 minutes depending on initial battery level.

Faster overall charging time is quicker with very low battery levels but I view this as a high risk, low reward strategy. Adding 15 minutes to my is insignificant compared to the consequences pushing the envelope and running out of battery.

A wide range of solutions are within 15 minutes of the "best" solution. To me, that does not matter. Don't obsess over charging stops/battery levels etc. Charge when the battery is down around 20% or so, charge for 20 to 25 minutes an add around 60 kWh.

Eight minutes of overhead might be on the high side the the 2nd chart shows a 4 minute over head simulation.

8 min OH.jpg



4 Minutes of overhead:
Points to Make:
With less overhead a 6 stop strategy might be ever so slightly better than the 5 stop strategy.
Again, many solutions are within 10 minutes of the "best" solution. Don't obsess over it.

Speaking of obsessing... A well known YouTube Influencer seems to be very obsessed with charging speeds and strategies. The 10% challenge test with 15 minutes of charging time is held as an example of a smart road trip strategy. Strictly speaking, 15 minutes of charging time is demonstratively NOT the best solution for the Rivian vehicles. It is not significantly worse that the best and it might be the best for other vehicles but not for Rivian vehicles.

4 min OH.jpg



For completeness the chart below included how much time it would take if you initiated every charging session with a pretty full battery. It could add over an hour to your trip time.

8min OH 4 curves.jpg



Bonus chart:
Supercharger vs Electrify America; I can break it out by initial SOC but lumping everything together shows the Superchargers and EA to be, on average, the same for charging times.

Charge Time EA vs SC.jpg


8 min OH.jpg
I totally concur with your calculations and results. While my experience is almost totally anecdotal, My Gen1 Quad T is at least as economical (especially in conserve mode) as my Gen1 Dual S. Perhaps part of that is due to the difference in shape and size between the two vehicles but the bottom line is that the Dual doesn't give me the improved efficiency as much as I thought it would.
 

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Great post!

The "10% challenge" video" you referenced above showed adding 42.5 kWh in 15 min (horrible charging according to "Out of Spite Kyle" @moosehead).

Under "ideal" circumstances with no "de-rating", we should expect to add around 50-52 kWh of energy (200+ kW, if we start from 10-20% SOC).

Looking at your charts, it would seem that you have experienced a range of outcomes that roughly span these two extremes (i.e. between 40-50+ kWh added in 15 min).

So sometimes charging power holds near 200+ kW through most if not all the first 15 min, but other times if either derates more quickly or doesn't ramp up as quickly to max power. Your data also show that if your goal is to add 60-80 kWh, you should expert charging stops to vary from about 25 to 35+ min.

So the question is: Why the variation, and is the variation typical for EVs or just Rivian?

As a Gen 1 R1s quad owner I see very little motivation to consider Gen 2 as an upgrade, but I would seriously consider upgrading to a Rivian that can charge at 300+kW and consistently hold that power for 15-20 min. If GM (Silverado) can do this why not Rivian?

Again great post!
 

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Rick, you are amazing. I love this post.

I am surprised the heat pump is not making a measurable difference in cold temperatures. I wonder if you will see a trend after you get more data points. That said, I think the difference is likely to be less than 10%, so considering all the other variables, it may be hard to pick that one out as the cause.

If I lived in MN, I would insulate the glass roof. That has to be adding significant heating overhead to each trip. But even with good insulation on the glass, the difference will be hard to measure. A 2-3% improvement would add less than 10 miles in cold temps. Still, I would take it!
 

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I totally concur with your calculations and results. While my experience is almost totally anecdotal, My Gen1 Quad T is at least as economical (especially in conserve mode) as my Gen1 Dual S. Perhaps part of that is due to the difference in shape and size between the two vehicles but the bottom line is that the Dual doesn't give me the improved efficiency as much as I thought it would.
I've posted my thoughts in other threads. Basically, the biggest consumer of energy at higher speeds is aerodynamic drag. That will compromise most of the energy consumption in most vehicles once you get about 40 mph. The faster you go, the greater the energy used to overcome aerodynamic drag as a proportion of overall consumption.

Aerodynamic drag increases by the square of the speed, HP required by the cube. It is an exponential increase, whereas rolling resistance is more of a linear function.

So, let's assume we improve efficiency by 10% for the motors and drivetrain. That may matter more on the slow speed EPA testing than at 70+ MPH since you are only improving efficiency on the part that is a smaller portion of the overall drag as you increase your speed.

Or looking at another way, let's say that non-aero drag accounts for 50% of total drag at 40 mph. If you double the speed to 80 mph (like out of spec), that non-aero drag is not 50% anymore. It will likely be only 20% or less. I don't have time to run the numbers but work with me here. So perhaps a G2 truck is 10% more efficient than a G1 (on EPA testing so about 45 mph avg). So we saved a whopping 10% (insert sarcasm), but that applies to the smaller portion of the energy consumed at 80 mph (but it sure looks impressive on an EPA test). So, at higher speeds, the improvement will be much less than at lower speeds.

Now, if I really wanted to improve efficiency on the highway, I'd do more massaging of the aerodynamics if I could. The faster I go, the more that will matter.

That is why I wasn't sold on a G2 truck when coming into Rivian net new.
 
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Great post!

The "10% challenge" video" you referenced above showed adding 42.5 kWh in 15 min (horrible charging according to "Out of Spite Kyle" @moosehead).

Under "ideal" circumstances with no "de-rating", we should expect to add around 50-52 kWh of energy (200+ kW, if we start from 10-20% SOC).

Looking at your charts, it would seem that you have experienced a range of outcomes that roughly span these two extremes (i.e. between 40-50+ kWh added in 15 min).

So sometimes charging power holds near 200+ kW through most if not all the first 15 min, but other times if either derates more quickly or doesn't ramp up as quickly to max power. Your data also show that if your goal is to add 60-80 kWh, you should expert charging stops to vary from about 25 to 35+ min.

So the question is: Why the variation, and is the variation typical for EVs or just Rivian?

As a Gen 1 R1s quad owner I see very little motivation to consider Gen 2 as an upgrade, but I would seriously consider upgrading to a Rivian that can charge at 300+kW and consistently hold that power for 15-20 min. If GM (Silverado) can do this why not Rivian?

Again great post!
My guess on charging variation Is that it is due to temperatures. Temperature of the battery, variation in preconditioning effectiveness and charging equipment temperature.

I really didn’t understand Kyle’s “outrage” over the max pack charging speed. YouTube drama to get clicks I suppose.

I agree Gen2 is not much of an upgrade for the user but Rivian can make a profit from it which is a big point to keep in mind.

Everybody's use case is different, you would like higher speeds. I would not turn it down but not at the expense of less range. In my neck of the woods fast chargers are rare and I frequently travel where there are none so I’m hale to have the max pack.
 

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Good stuff. I've been thinking we need something like this for driving speed vs efficiency. Driving faster can get you there quicker except it increases your charging time. Might be another variable to try to factor into your charts? A Monte Carlo or optimization function might be the way to go for that.
It's faster to drive faster.
let's say
80mph is 1.8
60 mph is 2.0
driving 80 miles
its 20 min difference in drive time
and around 4.44 kw difference in energy
Fast charger going 135 would only be 2 extra mins.
Also you'll be slightly deeper in the battery which equates to faster charging speed.

In summary a few more mins on the charger is faster than driving 25% slower.
 

JeromePowell

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Great post!

The "10% challenge" video" you referenced above showed adding 42.5 kWh in 15 min (horrible charging according to "Out of Spite Kyle" @moosehead).

Under "ideal" circumstances with no "de-rating", we should expect to add around 50-52 kWh of energy (200+ kW, if we start from 10-20% SOC).

Looking at your charts, it would seem that you have experienced a range of outcomes that roughly span these two extremes (i.e. between 40-50+ kWh added in 15 min).

So sometimes charging power holds near 200+ kW through most if not all the first 15 min, but other times if either derates more quickly or doesn't ramp up as quickly to max power. Your data also show that if your goal is to add 60-80 kWh, you should expert charging stops to vary from about 25 to 35+ min.

So the question is: Why the variation, and is the variation typical for EVs or just Rivian?

As a Gen 1 R1s quad owner I see very little motivation to consider Gen 2 as an upgrade, but I would seriously consider upgrading to a Rivian that can charge at 300+kW and consistently hold that power for 15-20 min. If GM (Silverado) can do this why not Rivian?

Again great post!
"Why not Rivian?"

...because their battery pack thermal management would need to improve and more importantly they would need a nominal 600v - 900v pack voltage to reach 300+ kW and hold it (near it) for any length of time.
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