Efficiency - Too good to be true?

[Surferdude]

Almost 32,000 miles in my (2024 Dual Motor Large) R1S.

Efficiency is 2.09 mi/kWh

I'm at a very accurate (confirmed with amp meter) 1.98 mi/kWh over 9,000+ miles in our R1S LE. Warm climate all year. Never under 60 degrees and never over 85 degrees. Don't drive like a maniac or ever exceed 65 mph. Unless one is going downhill, I would say it's impossible for a reasonably consistent efficiency over 4 unless you're puttering along at 30 mph on perfectly flat pavement with zero wind, all windows rolled up, and no climate control.

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[JM.]

I have heard the range estimate on the display called the "Guess-o-meter". Because that is what it is.

It is now, it was not in the past. A lot of people reported increased Guess-O-Metering from the newest software update. I watched 70 miles evaporate in about 30 miles. And then the last 5 miles disappeared in ten minutes while parked. I think Rivian saw this on the logs, and ended up paying for everything instead of blaming me.

 

[sherold]

I'm curious to see if SW update 2025.14 "secretly" reverts/revises the efficiency graph back to display more cumulative efficiency numbers. The latest calculation method is very misleading.

 

[portdirect]

I have seen posts that indicate that maybe the GOM uses driving history to help determine the estimated range. If that is true, it should be more accurate. If all it does is default to the EPA range, then of course your range will be worse unless you drive in a way that is as efficient as the EPA test. Most people rarely drive that efficiently.

All it does is use a fixed multiplier for each drive mode/tyre combo against the remaining battery capacity - there is no input from recorded driving habits etc. The 'reset' button in the energy does nothing with regard to the range calculation currently - other than provide a clear timestamp for internal logging of driving energy consumption performance etc. This came straight from the diag team - who are monitoring my truck currently - though thankfully since its last trip to Normal has been operating with great (ie expected) efficency.

 

[mkhuffman]

All it does is use a fixed multiplier for each drive mode/tyre combo against the remaining battery capacity - there is no input from recorded driving habits etc. The 'reset' button in the energy does nothing with regard to the range calculation currently - other than provide a clear timestamp for internal logging of driving energy consumption performance etc. This came straight from the diag team - who are monitoring my truck currently - though thankfully since its last trip to Normal has been operating with great (ie expected) efficency.

This is actually hilarious. When I first purchased my Mach-e, it was using driving history to reflect the estimated range on the display. Guess what happened? People who purchased the car got upset because they thought they got the wrong battery or there was something wrong with their car because the range displayed was much less than what they thought it should be.

So Ford reduced or eliminated the impact of driving history and the complaints went away. Rivian must have figured out that people expect to see EPA range on the display even though they have never driven efficiently enough to reach EPA range.

The truck knows, but it ignores driving history because people are stupid. They will actually think they have the wrong battery installed in their vehicle. And then they will return their truck to the service center and demand it evaluated and fixed.

 

[Engineer]

Whether the efficiency based on time (regardless of speed, distance, elevation, etc) and the efficiency based on distance (regardless of speed, time, elevation, etc) "match" is a mathematical question, the answer to which you haven't provided enough data.

I'm not a mathematician, but i respectfully disagree. how can the average efficiency based on distance be significantly lower than the lowest instantaneous efficiency based on time for the same distance/time period... that just doesn't make any sense.

my point was, they have more or less matched in the past, at least directionally. since the last update or two they have diverged significantly. I have 20" AT's and my "instantaneous" effeciency is now consistently above 2 and sometimes gets pegged at 4+ for long stretches.... although i wish it were true, that's just not real. Something changed with the way the graph calculates the instantaneous mi/kwh and it seems to be artificially high.

 

[a76marine]

Not to bring up a slightly old thread, but I agree that the last update 2025.1 absolutely changed the GOM calculations. When sitting still in drive (red light, parking lot, car wash, etc) the efficiency goes up to 4.0 (and I am thinking it's actually infinity) and that's being calculated into the previous 15 minutes. It's not right and I'm hoping it's being addressed in this new update.

Driving habits... EPA Estimate... I don't care, just want it to be close to accurate.

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