# Forums

## 373 miles

## 373 miles

Hello fellow Tesla owners. This is my first post.

I am a proud owner of a Model S long range with the raven update. The purchase was made on September 28th. Undoubtedly I am very fond, and it is pure pleasure to drive.

In the six weeks the car has been in my possession, it has reached a total of 3,475 miles per odometer.

I'm asking for feedback and opinion to determine if something is reasonable or not.

Generally an upper limit of 80% charge is where I have maintained the car and I didn't put too much thought into the numbers. Recently I discovered that 100% charge gives 352 miles range.

I hadn't bothered to analyze this until I noticed a recent update claimed to increase the charge by a small percent resulting in range of 373. Obviously this wasn't true in my case.

What should I think of this situation?

Your thoughts please.

Jonathan

murphyS90D| 21 novembre 2019The range is a mathematical calculation. There is no way to measure the energy in a battery, only what is put in and taken out. Over time the calculation loses accuracy if the whole battery isn't included, that is 0 to 100%. Since both of those extremes are bad for the battery the loss of displayed range is not avoidable.

The range number is only valid if the car is driven at the exact conditions used in the EPA test that determined. it.

You can get much higher range if you drive continuously at 25 mph.

In other words don't worry about it. The warranty only comes into play for catastrophic failure inside of the battery. It does not cover battery degradation.

My battery failed at 920 miles on the odometer. Maximum charge was 100 miles. They replaced the battery. They did not tell me what failed.

Anthony J. Parisio| 21 novembre 2019murphyS90D is right in all he wrote. Adding to that you can look at the average range over the past 30 miles you drove. This is will be greatly affected by your driving style. All in all nothing to worry about . Just drive and enjoy.

Bighorn| 21 novembre 2019Others have reported similar range numbers. I wouldn’t give it any more thought.

skybluewater| 21 novembre 2019Thanks for the thoughtful responses!

I won't obsess over this and will just enjoy my car.

While I have your attention, please provide your thoughts regarding what is a reasonable amount of battery degradation to expect if 100 thousand miles is reached over the next 4-5 years? I realistically can see myself possibly doing that.

All the best!

Bighorn| 21 novembre 2019I was down 11.5% at 197k. Probably half that at 100k

marcustcohn| 22 novembre 2019@skyblue - I also took delivery of S100D long range and my battery was not fully charged but I did the math and computed at 100 percent it would show 354 miles and had the same questions.

However, what I have focused on subsequently is watt hours per mile - if a 100 Kwh battery is supposed to deliver 373 miles then the whr/mile number needs to be 268. As has been stated the 373 is under strict EPA conditions that normal driving will not achieve so real life range is dependent on speed, heating, accelerations, etc. And how likely are you to start at 100Kwh - more likely 80 and you are not going to drive to zero - more likely 10 or more so your 'real' battery size is say 70 Kwh and at 285 whr/mle (somewhat more realistic) that is 245 miles.

Bighorn| 22 novembre 2019@marcus

Plenty of conditions allow for matching EPA range. Also, the batteries seldom match the capacity. It’s pretty close on the 100s but 85s had less than 74 kWh available for locomotion. Hence the math is never on point without knowing the actual kWh figure.

skybluewater| 23 novembre 2019For readers that wishes to see more depth on this subject, they may find this video useful:

https://youtu.be/UXwtlKHSefk

marcustcohn| 23 novembre 2019@BH - I agree one can match up to EPA conditions notably around town but who drives 65mph on a long distance trip? And how often is it 70 degrees, flat, no wind ? What do you estimate a realistic whrs/mile would be for normal long distance trip assuming somewhat conservative driving ?

Bighorn| 23 novembre 2019@marcus

My general ballpark on range is 2 miles per %, but I tend to cruise between 80 and 90. I use this in both cars for deciding when I’ve charged adequately. EPA machinations have little bearing on my ability to roadtrip. Currently, I’m in my slow charging S and will do 2000 miles in just over 2 days, but I’m taking it easy because I’m traveling with my wife and dog.

marcustcohn| 24 novembre 2019@BH - Amazing - i can see how you can get the daily mileage at those speeds. But then I also see that you would need to stop at most/all SC - if I am doing my math correctly ???? your watt hours / mile would be around 400 or more. Using this 'splash and dash' method what is the comfortable distance between SC stops ?

Bighorn| 24 novembre 2019Doesn’t matter how fast you drive, you can’t really average much over 50 mph in the older models. Peak average speeds level off and decline after 80. In states with 80 mph limit, 400 Wh/m is about right. It’s closer to 350 in 70 mph states. I’ve always made a point of stopping at every charger because of my early days in the competition to visit them all. I’m at 776 now with the addition of Lake Geneva. Only one new charger in my 2000 mile drive this time. Looks like the weather and holiday traffic might hamper visits to both Canada and North Carolina on this excursion. I like stopping every 100 miles—I think 155 was my longest leg this weekend.

rxlawdude| 24 novembre 2019@Big, same with the S70D - (REAL WORLD) 2mi/%consumed relationship here, too, meaning the EPA 240 mile range when new is around 20% optimistic just to start.

This jibes with the M3 RWD LR getting around 2.5mi/%consumed meaning a real world range around 250 miles. However, the furthest I've gotten on a road trip was between Sacramento and Kettleman City, 218 miles from 96% to 7% (2.44mi/%consumed) with average speed of 70 and max 85.

marcustcohn| 24 novembre 2019I have tried a few times to try and figure out the trade off between 'splash and dash' and the opposite which is to charge more and drive further. The issues in opposition are I think, time to find a SC site and return to the road vs. the taper as SOC passes 60-70 and then to 80 - I think the taper after that get more and more severe. If you ride a route where you know the SC locations from memory that helps but if you are on a new route sometimes it can eat up extra time just finding the site. Has anyone seen anything analytical about the taper curve vs SOC ? What is your estimate of how long to exit the interstate park at a SC and then return ?

Bighorn| 24 novembre 2019The speed to efficiency of average rate of progress was plotted for the S85 and the optimal speed peaked and plateaued between 78 and 82. There was also an interdependence on distance between chargers. The calculus changes with the advent of quicker charging, now 250 kW vs 120 kW, at the time. It’s reasonable to assume that the optimal speed is now much higher given replenishment rates. The taper on the S was almost linear starting very early since the maximal sum of SOC and kWs was about 132, so in essence the taper has begun almost on a one for one basis at 15%.

Reds Tesla| 24 novembre 2019I'm coming to realize that getting stuck on numbers like 373 is a waste of time! Conditions make such a difference in range. I live in the Boston area with a new S, and have found with the sudden drop of temps into the 30's and 40's, my range has dropped almost 30-40% on short trips where the battery starts out cold. Driving 30 miles typically takes 50-55 miles off the range! I'm not sure what's going to happen when it really gets cold, but I can see that pre-heating the battery will make a tremendous difference for some trips. However, warming the battery uses about 6 miles per hour, so it is hard to calculate if it is more efficient to just drive with a cold battery using more energy, or spend the time to warm the battery and have a more efficient trip. Good luck figuring this all out, but if you charge to 80% every night you have plenty of range.

marcustcohn| 25 novembre 2019@BH - You introduced some really important numbers - the optimal speed - what is this all about ? Is can't be the watt hours per mile so what does optimal mean ?

Then there is the constant 132 as the sum of SOC + kWs - does this mean that if I start at 10% SOC that I could possibly draw 122 KWs and at 60% my maximum would be 72 kWs and so on?

Really important stuff to know and use in long distance planning.

@Reds - all well and good if you are home but what about cross country in the winter ? No choice but to warm the battery and from what I have gathered it would be better to just start driving unless you are at a SC in which case you could turn on cabin heat and charge but probably at a very slow rate until the battery warmed up.

NKYTA| 25 novembre 2019"Then there is the constant 132 as the sum of SOC + kWs - does this mean that if I start at 10% SOC that I could possibly draw 122 KWs and at 60% my maximum would be 72 kWs and so on?"

That is what he was implying.

"Really important stuff to know and use in long distance planning."

Take a long trip, say, 5,000 miles. You'll then be able to intuit any questions you've had on this thread, I predict.

Bighorn| 25 novembre 2019@marcus

The optimal speed is what gets you to your destination quickest over a long trip. With the S85, optimal progress is about 50 mph. Subsequent batteries have raised that. Notably the 100 kWh battery charges about 35 kW higher and Model 3 is better yet. Max charging is around 118 kW, so 122 would not be seen back then. With newer firmware, the top rate has dropped and the sum is now closer to 113 on the old 85s. 3s max at 250 kW and have a more complex taper.

The 132 max sum as confirmed by NKYTA is not quite linear, but it is useful to determine if you’re getting an expected supercharger rate. The more nuanced formula is SOC + kW = 125 +/- 7 with the variances occurring at the extremes. i.e. 132 at low SOCs and trending toward 118 near full.

marcustcohn| 25 novembre 2019My trips have all been in the summer so far and range from 1,000 to 2,000 miles. In early models I saw the actual fall steadily below the predictive line when I went 75mph or more. But in the last two this speed did not seem to affect the predicted range and the lines stayed pretty constant. I had thought then that it was just Tesla tweaking the algorithms but now it may have been motor and drive train improvement.

Bighorn| 25 novembre 2019The trip predictor has gotten much more accurate. In the past, it could have been off by a 30 point shortfall. Now it’s as likely to be off in either direction by just a couple points. Two trips today, I arrived with 4 points more than predicted despite driving 10 over. I think it “knows” I have a heavy foot.

Bighorn| 25 novembre 2019There has been an improvement in efficiency over the years. Funny how people are so keyed in on battery “degradation” and not the offsetting improved efficiency.