Performance not getting 310 miles promised

[AlanSubie4Life]

The EPA rated range is based on a mixed drive cycle, not any particular steady state speed. For any given EV, there will always be a steady state speed that achieves the rated range under certain ambient conditions but that is not what the rated range represents.

Note I did not say EPA range. I was just saying the range of the vehicle is relevant when driving at highway speeds, and usually not any other time.

That is why I did not quote the rated range. Obviously you can expect a few less if you are doing all highway or you up your speed. That is why there are the Teslike tables, which may be accurate in ideal conditions. It isn’t rocket science.

The rated range represents some very specific conditions which may or may not be reproducible, but remember the city cycle might not be as good as you think because of the stop-start nature of it, which will hurt due to the regen losses. In the end it’s less than 10% difference in efficiency per the testing data between the two. So given the weighting you only have to dump 5% or so off the rated range. Also implies when city driving there is a lot more room to hypermile it...since it is pretty easy to drive the car more efficiently than the EPA city cycle. But on the highway not much you can do other than slow down.

After considering this new data I believe I will change my routing plans and charge at the Steele, AL Supercharger and then again at the Greenville, AL Supercharger.

Up to you of course, but I am fairly confident that starting with near 100% charge and proper tire inflation, and no inclement weather, you will be able to make your proposed trip without difficulty. Whatever makes you feel most comfortable.

 

[AlanSubie4Life]

Just today I took my daughter out for a ride in the car. 62 miles roundtrip with all but 5 miles on the highway at an average of between 60 and 70 mph with the A/C on at least 50% of the time (set at 70 degrees and it was 74 degrees out). Little to no elevation gain. We averaged 252 Wh/mi and that included several very spirited accelerations.

Well, maybe you have a gem! As I said, I will report back after my journey to Anaheim! It is 93 miles (with elevation loss of about 650 feet...). Maybe I will be pleasantly surprised! I’m going to guess 265Wh/mi if I average 70mph with max speed of 80mph. If I end up being slower (60mph average) with heavier traffic, I’ll guess 250Wh/mi. I figure I will use 100-110 rated miles even with the 4-mile bonus from the elevation. I figure my extrapolated range will work out to be less than 300 miles, even with traffic to draft off of and the elevation loss. I promise to not use the brake except for coming down the hill from my house (minimally) or emergencies - I need to be fully charged to start, since I do not want to be forced to hit a Supercharger later in the week, and want to leave the car parked with more than 50% battery. (I figure I will arrive at about 65%.)

For your trip, what was the time spent driving for the 62 mile drive, exactly? This helps with calculating the average speed. Obviously the average speed is not all that matters, since drag losses are a nonlinear function of velocity, but it is an important metric all the same. If this trip took an hour and 6 minutes, your number would be completely believable. Light traffic to draft off of also helps tremendously, and I generally expect you could maybe hit the range in those conditions, if you kept your speed below 65mph.

Spirited acceleration seems to have relatively little impact on range when not paired with deceleration. Have to get the kinetic energy somehow, and to first order it does not matter how fast you dump it in!

If what you are saying is correct, there is really no point in me buying 18” MXMs for road trips, so we will see!

 

[StealthP3D]

But on the highway not much you can do other than slow down.

You don't have to slow down if you don't drive too fast to begin with!

That's even more efficient.

 

[mswlogo]

You cannot get that rated range anywhere near as easily as in a RWD car. I have owned both and the RWD car could EASILY get 200-220 wh/mile. With the same exact style of driving, P3D can maybe get 280-300 wh/mile.

P3D-
230 miles highway at 65 mph
20 miles 30-45 mph
19” OEM Wheels at 42 psi
To destination was 42F with just a little heat. Return trip was 65F fan only.
Plenty of hills.
Central MA to Central NH and back.
Chill mode (but I would drive exactly the same if it was off)
25% Limited Regen for half the trip

That translates to 380 miles range.

 

[AlanSubie4Life]

With the same exact style of driving, P3D can maybe get 280-300 wh/mile.

Presumably that number is with your fat tires and stuff though? My friend @Daniel in SD routinely gets above 330Wh/mi or so (in his AWD), with PS4S 265mm section width tires, and when he puts the bike on the back it's over 400Wh/mi! Personally it kind of seems like there is something wrong with his car, but he also does has some hills to deal with. He also uses the brakes. Shameful.

P3D-
230 miles highway at 65 mph
19” OEM Wheels at 42 psi

- The wheels don't matter that much! - you should specify your tires - Pirelli P7 Plus if I recall? Or was this before those tires when everything was OEM?

- Pretty impressive. Any traffic to sit behind (any effort made to do so at a following distance of 5 or so)? Seems very believable based on the mostly 77mph 247Wh/mi result (with MXM4s). I need to dig up those curves to figure out what proportion of the loss is aero and then we could fit everything. I guess @Troy has tried to do this already based on the provided coefficients. I don't trust curve fits though...

- How many rated miles used? (I would guess about 222 rmi.)

That translates to 380 miles range.

I can't calculate this number. I come up with ~345 miles assuming 77.5kWh available energy (the EPA test documents indicate it might be possible to draw more than 78kWh from the battery before it is well & truly dead). You used 55.37/77.5 = 72% of that which would mean you have ~345 miles available, in total. Which is excellent and should make everyone extremely happy.

 

[AlanSubie4Life]

You don't have to slow down if you don't drive too fast to begin with!

That's even more efficient.

Not faster though! There's no way on a trip across the Desert Southwest I am going to be traveling any slower than about 75mph, and often it will make sense to get close to 85mph. Have to keep up with traffic, and you can't get anywhere at 60mph. Obviously the range will suffer tremendously. I don't expect to hit the rated range with the PS4S, nor do I expect to hit it with MXM4s if I am going over 80mph.
This is just like any car. When I did this in my Highlander I saw the worst efficiency ever - about 20MPG, rather than the normal 25MPG which it always is at (city and highway) (I did have a very stiff headwind too so effectively it might have been 90-95MPH).

 

[kbecks13]

Presumably that number is with your fat tires and stuff though? My friend @Daniel in SD routinely gets above 330Wh/mi or so (in his AWD), with PS4S 265mm section width tires, and when he puts the bike on the back it's over 400Wh/mi! Personally it kind of seems like there is something wrong with his car, but he also does has some hills to deal with. He also uses the brakes. Shameful.

Back when i had stock everything i still could barely get 280 if i went 70mph. Now i get around 300-310 at 70 mph and 330-340 at 75-80.

 

[Keith909man]

Back when i had stock everything i still could barely get 280 if i went 70mph. Now i get around 300-310 at 70 mph and 330-340 at 75-80.

What isn’t stock that’s getting you that kinda range?

 

[mswlogo]

- The wheels don't matter that much! - you should specify your tires - Pirelli P7 Plus if I recall? Or was this before those tires when everything was OEM?

- Pretty impressive. Any traffic to sit behind (any effort made to do so at a following distance of 5 or so)? Seems very believable based on the mostly 77mph 247Wh/mi result (with MXM4s). I need to dig up those curves to figure out what proportion of the loss is aero and then we could fit everything. I guess @Troy has tried to do this already based on the provided coefficients. I don't trust curve fits though...

- How many rated miles used? (I would guess about 222 rmi.)

I can't calculate this number. I come up with ~345 miles assuming 77.5kWh available energy (the EPA test documents indicate it might be possible to draw more than 78kWh from the battery before it is well & truly dead). You used 55.37/77.5 = 72% of that which would mean you have ~345 miles available, in total. Which is excellent and should make everyone extremely happy.

Your right, sorry, I screwed up. Actually I use 75kWh and now come up with 334 range. 380 did seem too crazy good. Maybe if I put 50 psi and drive 55 mph

Yes P7 + tires.

I didn’t track rated miles used.

 

[redgt]

P3D-
230 miles highway at 65 mph
20 miles 30-45 mph
19” OEM Wheels at 42 psi
To destination was 42F with just a little heat. Return trip was 65F fan only.
Plenty of hills.
Central MA to Central NH and back.
Chill mode (but I would drive exactly the same if it was off)
25% Limited Regen for half the trip

That translates to 380 miles range.

380 no way

right under trip A show me a screenshot that says 70 kWh used

you used 78% of battery to get 248 miles

248/.785=316 mile range

impressive for sure. especially with your build but based on the screenshot its not getting you 380 miles on a 100% charge

 

[StealthP3D]

What isn’t stock that’s getting you that kinda range?

Maybe he's been showing his patriotism with one of these:

 

[redgt]

Your right, sorry, I screwed up. Actually I use 75kWh and now come up with 334 range. 380 did seem too crazy good. Maybe if I put 50 psi and drive 55 mph

Yes P7 + tires.

I didn’t track rated miles used.

my bad. i didn't see this reply before replying to your earlier post

 

[AlanSubie4Life]

What isn’t stock that’s getting you that kinda range?

He was actually talking about Wh/mi, not range. To get the rated range, you'd need to get below about 250Wh/mi. He's getting 330-340Wh/mi (due to his 9.5in wheels with 265 section width tires), so he'd be happy with getting about 240 miles for a 100% to 0% discharge. (Probably he would not get that 240 miles.)

 

[astrowunder]

Now that winter is over, I'm usually well below 300 with my P3D- Well except for a few hours the other night when I was over 1100 Came in 1st in open class at my local track drag racing. Man I highly recommend that- too much fun!

 

[AlanSubie4Life]

had stock everything i still could barely get 280 if i went 70mph

Yeah, this was definitely close to my experience this winter, even though I usually turned OFF the climate control (and disregarded data when I turned it on). Hence my incredulity about some of the PS4S numbers claimed here. I know how to drive efficiently...but there is no way to avoid driving 70-80mph on the freeway; it's kind of the minimum safe speed.

However, I feel that there has been some improvement as weather has warmed, so I figure the battery is operating closer to its ~100 degree optimal temperature now.

So, we'll see on the Anaheim trip! It's not much of a trip, but I do promise to report with my spectacular numbers. I do expect it will be quite good on the way there - 700 feet over 93 miles is not insignificant! (Normally I can get to work with about 150-160Wh/mi with 500 feet drop, so that's still going to help even over a distance of 10x as much.) I'll try to remember to report some overall round trip numbers too.

 

[Jedi2155]

I know this pic is terrible but I took the pic just as I plugged in and forgot it would reset my SOC before doing so. I really think these cars only have about 70-72 kWh usable before it hits 0%.

P3D+
Sedona AZ - > Quartzsite, AZ (Supercharger)
251 Wh/mi on stock 20" tires over 246 miles.
Weight was roughly 2028 kg (stock weight+2 passengers and cargo).
Elevation change was 1036 meters
Energy due to downhill was m*g*h = 5722 Wh.
If it was flat ground, my effective efficiency would've been: 251+23.3 = 274 Wh/mi.
Used up 86% of the battery on the trip.

TeslaFi details:
Total Elevation Change:

 

[UngaBunga1989]

You cannot get that rated range anywhere near as easily as in a RWD car. I have owned both and the RWD car could EASILY get 200-220 wh/mile. With the same exact style of driving, P3D can maybe get 280-300 wh/mile.

From everything that I have read, I am certain that the RWD is more efficient than the M3P. But that is not what this thread was originally intended to address. I am pretty certain that if I drove a RWD with Aero wheels I'd be getting significantly better than I do on the Performance. That said, I can (and do) get the advertised range (or better) on my Performance...as long as I drive reasonably and do not use a lot of heat.

 

[SammichLover]

Back when i had stock everything i still could barely get 280 if i went 70mph. Now i get around 300-310 at 70 mph and 330-340 at 75-80.

Yeah but at least one piece of that "not stock" gear is specifically to reduce drag, right? You still have he front, lower UP lip on?

P.S. I'm trying to figure out if that'll look awesome or look like total butt if I can figure out how to get it on around my wrap (which is 3M + on the front bumper a PPF top layer).

P.S. I know the rear lip looks kinda out there, but those numbers.....

 

[AlanSubie4Life]

I really think these cars only have about 70-72 kWh usable before it hits 0%.

The EPA documents seem to suggest about 79kWh before it is dead.

https://iaspub.epa.gov/otaqpub/display_file.jsp?docid=46585&flag=1

The meter in the car may read a few percent low. Even for no sitting after a charge and just driving I can’t get it to compute to even 75kWh normally...

Your numbers seem about right; I assume you were moving pretty quickly (70+?)

That said, I can (and do) get the advertised range (or better) on my Performance...

To be continued, I guess. I pretty much believe your numbers, if your speed was generally about 50-60mph. Can’t really believe the numbers at 60-70mph.

You may have a motor from the ultra low loss bin of course. Meanwhile mine power limits with 92% SoC at 45mph. So maybe I just have higher internal motor losses. My rear motor does not have a label on it, so it may be one they picked up on the gray market in China to meet their production goals?

 

[UngaBunga1989]

The EPA documents seem to suggest about 79kWh before it is dead.

https://iaspub.epa.gov/otaqpub/display_file.jsp?docid=46585&flag=1

The meter in the car may read a few percent low. Even for no sitting after a charge and just driving I can’t get it to compute to even 75kWh normally...

Your numbers seem about right; I assume you were moving pretty quickly (70+?)



To be continued, I guess. I pretty much believe your numbers, if your speed was generally about 50-60mph. Can’t really believe the numbers at 60-70mph.

You may have a motor from the ultra low loss bin of course. Meanwhile mine power limits with 92% SoC at 45mph. So maybe I just have higher internal motor losses. My rear motor does not have a label on it, so it may be one they picked up on the gray market in China to meet their production goals?

I have also been driving EV's since 2011 and I really do believe that counts for something. Knowing when to lift and let Regen do its thing, how to accelerate gradually up to speed, looking way ahead on the highway to gradually slow down when traffic does for max Regen? All of those things collectively pay huge dividends. I can also drive the car like I used to drive my Ferraris -- and that reduces efficiency by at LEAST 100 Wh/mi...BOTH ways of driving are tremendously enjoyable and have their time and place and that is what I absolutely adore about my M3P...it CAN do both.