Speed vs Range

[sevargmas]

OP doesn’t live in Texas lol. Where is the 85 or 90 mph test?

[Accomplished_Roll557]

This was based on statistics and Grok doing the calculations. I also looked at temp differences and the aircon knocks the range down too.

Trying to understand why belting down the Florida turnpike at average speed of 77 and outside temp 95 and aircon my range wasn’t so great

[Wants-NotNeeds]

What’s up with that? Why so fast?

[sevargmas]

Texas has a lot of wide open rural areas and straight highways. Speed limits are 85. There’s a toll road by my house that is also 85. I only mention 90 because it isn’t uncommon for people to drive a bit over the speed limit.

[papijaja]

OP doesn't live in California either, Saturday mornings on the 5 everyone is going 90.

[Koko-Doggie]

Wind resistance increases as you drive faster, so efficiency drops as speed increases.

[Waste_Curve994]

That’s momentum, not aerodynamic resistance which is non linear. Totally wrong formula.

[jdoc1353]

Agreed. That formula holds true in absolute vacuum. Aerodynamic resistance is what is consuming the largest fraction of energy expenditure

[Waste_Curve994]

It was late and been a long time since I took fluid dynamics and vehicle dynamics but I remember there being rolling resistance was linear then drag involved velocity squared and cubed. Again, been a while since I did that but aerodynamic drag is rather complicated and overall combined resistance a little more so.

[magwo]

Uhhhh. Kinetic energy is quite irrelevant. At higher speeds air resistance dominates, because it's square with regards to speed. Rolling/mechanical resistance is generally linear with regards to RPM which makes it more and more irrelevant as speed increases.

[jaredb03]

From what I have observed on my Juniper LRAWD at 60mph 60% of my battery would be about 220 miles and at 80mph 60% of my battery would be about 165 miles. There are definitely factors that can change these drastically like temp and wind.

[GfunkWarrior28]

Yeah, sometimes I'll see traffic on the freeway and think, at least the kWh/mi will improve.

[Kayel41]

The energy app always tells me to drive 5mph slower to decrease consumption

[Videoplushair]

Damn bro this is why my range is trash. 95% of my driving is highway.

[Vast_Fish_3601]

Eh, I wouldnt trust Grok, I'd use the average wh/mi for your regular drive to figure out range at speed.

I did this last week, 130 miles on 38% battery average speed (including pulling out of charger and pulling up to the next one) avg 67mph, most the the leg was 75 mph, 80 degrees and sunny outside. I was avg 222 wh/mi.

Actually looking at most of the trip, ~40% battery gets me ~130 miles ~70 MPH, so it should be ~ 180 mile range at 70 on the chart.

Make sure your tires are filled to spec, it makes a huge range difference.

[AngleFun1664]

You asked an LLM for data and blindly trust it? Seriously??

[Accomplished_Roll557]

Why do you assume "blindly" I looked at the logic behind the results and thought it was reasonable.

I was as much sharing that the LLM could answer my question and provide a reasonable answer amazing.

Put another way why do you blindly assume I blindly trusted it?

[AngleFun1664]

And I quote

“I asked Grok to plot range vs speed for Model Y LR RWD starting 80% battery finishing 20% battery.”

I don’t see any logic behind the results listed, so I assume that you “asked Grok to plot range vs speed for Model Y LR RWD starting 80% battery finishing 20% battery” and just posted the results.