Realistic range...it would be great if it was more accurate

[Science fan]

My S70's (19" wheels) actual range is most often almost exactly equal to the rated range. I do not speed because I have some understanding of the physics involved in what will happen to the people who trust me to drive safely and to innocents in other cars. Driving at 85 mph needlessly risks the lives of everyone around you. You need to think carefully about what is most important to you and about what you are doing behind the wheel.

 

[jchag]

If you bring up the Energy App on the 17" screen you can see your estimated actual range based on your past or current driving conditions.

Mine only gives you range based on your prior 30 miles of driving. I think they are asking for the car to take the average wait/mile since inception ad use as the actual range

 

[msnow]

Mine only gives you range based on your prior 30 miles of driving. I think they are asking for the car to take the average wait/mile since inception ad use as the actual range

If you set a trip in Nav then click on the "trip" tab it will calculate what your actual consumption will be based on your past driving plus environmental conditions. I found it to be pretty accurate.

 

[Canuck]

. I do not speed because I have some understanding of the physics involved in what will happen to the people who trust me to drive safely and to innocents in other cars. Driving at 85 mph needlessly risks the lives of everyone around you.

We have some very nice divided highways up here like the Coquihalla that has a 120 km speed limit but the cops generally give a 10 km buffer before ticketing. That's basically 85 mph. In fact, the highway became safer when the speed limit was raised to 120 km/hr.

There's nothing dangerous about 80-85 mph on straight stretches with clear views and I'm not needlessly risking anyone's life when I drive at 85 mph on the highways here. Slow drivers are among the most dangerous on the road.

 

[RAW84]

Switch the display to report percentage of charge remaining.

Us Canadians and others in cold climates can use this kind of conversion factor for an 85 kWh pack:

90% summer = 300 km at "brisk" highway speeds
90% winter = 250 km at highway speeds with heating fully on

If you need a bit more range, range charge to 100%.

So, the solution is to use the percent multiplied by a factor of 3 in summer and 2.5 in winter.

Using % seems to be a popular opinion on here, but I can't fathom why. You can come up with similar conversion factors to convert the rated mileage to "actual" mileage as you do for %. So That's a wash. Unless there's some other advantage I'm missing.

The advantage I see in using rated miles is that I know the Wh/mi that leads to me getting that rated mileage displayed on the dash. I can quickly assess, as I'm driving, how close I'll come to matching that rated mileage by monitoring the trip Wh/mi and the last 30 mi Wh/mi, which I keep on the dash. This comes in handy as road conditions/plans change on the fly.

 

[Canuck]

Using % seems to be a popular opinion on here, but I can't fathom why...
I can quickly assess, as I'm driving, how close I'll come to matching that rated mileage by monitoring the trip Wh/mi and the last 30 mi Wh/mi, which I keep on the dash. This comes in handy as road conditions/plans change on the fly.

I keep an eye on my Wh/km because that gives me great instant data but I don't find it all that helpful on a trip when, for example, I have just climbed a mountain. Plus, I'm only concerned about range when on a trip and I always enter my destination, and that gives me an arrival percentage. That percentage drops in live time according to my driving, weather, etc., and I can view it against the battery's percentage. I find that to be the most accurate way to know if I can make it to my destination, allowing for a 10% buffer (at least) over the destination calculated range.

 

[mal_tsla]

We have numerous roads around here with posted limits of 75, 80, even 85.

Labeling these speeds as illegal or dangerous is unfair and heavy handed.

 

[dweeks]

I drive on I-17 and I-10 in AZ all the time back and forth to work. 75 is the posted limit.

If I drive 84 (9 over and no problems with getting ticketed) I am passed by as many cars as I am passing...

 

[Tony8489]

Set up and display the power usage screen to last 30 miles. The screen will display remaining range at the rate of the past 30 miles. Meanwhile the nav screen shows miles to destination. You can check that the former number exceeds the latter by a comfortable margin and whether the numbers are converging.

You need to factor in whether there is significant elevation gain/loss in either the past 30 miles or what remains to be driven. If not and the numbers above are converging you have plenty of notice that you might to slow down a bit.

I downloaded charts from this forum that show impact upon range of speed, elevation change and weather. Projected range from the charts is nearly always well within 20% of actual results.

We are fast drivers averaging close to 80mph on many trips and we consume about 350 wH/mi on those trips in our S90D. Interestingly our local driving in the LA metro area has similar power consumption. We get close to rated range only on scenic roads or moderately busy local freeways that hold average speed below 70mph.

 

[trils0n]

I like how the rated range number is always based on a consistent Wh/mile number (for the P85 it seems to be around 300Wh/mile). If I am using 300Wh/mile, as indicated by the energy app, I will get exactly what the range number says. If I am doing better than that (it is fairly easy to do 270-280Wh/mile for me) I get more range. If I'm using more energy, will get less range. Pretty easy, and I like that the EPA number of range is constant, cuz it is easy to see if I'm using more or less energy than the rating.

The Leaf had a guess-o-meter instead. If would fluctuate wildly based on driving behavior. Hop on the freeway, and you'd "lose" 25 miles. Let it settle down, and average out the energy use and the miles would "come back". Wasn't too useful to me.

Pull up the energy app (either on 17inch or instrument cluster) and it will give you a readout based on your driving, not on the EPA test. Put it on 15 or 30 mile history and it won't fluctuate like the Leaf display.

 

[RAW84]

I keep an eye on my Wh/km because that gives me great instant data but I don't find it all that helpful on a trip when, for example, I have just climbed a mountain. Plus, I'm only concerned about range when on a trip and I always enter my destination, and that gives me an arrival percentage. That percentage drops in live time according to my driving, weather, etc., and I can view it against the battery's percentage. I find that to be the most accurate way to know if I can make it to my destination, allowing for a 10% buffer (at least) over the destination calculated range.

Nav will display estimated battery percentage upon arrival whether you have the gauge set to display battery percentage or rated mileage, so that's not really relevant to this discussion.

I agree Wh/mi isn't all that useful when going through the mountains. Typically, you know when you'll be traveling through mountains and plan accordingly. But it's quite useful for other trips. Especially since you can see how your instantaneous energy usage has been trending over the last 30 miles in addition to the current average over that 30 miles and the cumulative Wh/mi for the trip.

And I disagree that the only time to be concerned about range is on long trips. Most of the times that I'm concerned about range is on unexpected trips. I get out of work and get a call to meet a friend. It's a 55 mile trip from work to restaurant to home (legs of 20 & 35 miles). If my car's at 33% can I make that trip? I have no idea. I'd have to use one of your conversion factors and hope I'm appropriately accounting for the weather conditions and my driving habits. 15 minutes into the trip, I'm 10 miles from the restaurant and the percentage drops to 28, am I still on track to make it? Answering that is more difficult to do whilst driving than when using rated miles as the gauge. The nav can tell me I will reach the restaurant at x%, but what % do I need to be at when I reach the restaurant to feel comfortable I'd make it home? Again, harder question to answer. If my car's on 81 rated miles when I leave work I know immediately I feel comfortable I can make that trip, since I have a basic idea on my Wh/mi in recent trips (similar weather). 15 minutes into the trip, I'm 10 miles from the restaurant with 65 rated miles left, I'm still immediately feeling confident I'd make it. I know if I arrive with 50+ rated miles I have nothing to worry about for my 35 mile ride home. No need for any conversion factors.

Then, of course, there's the inherent advantage to rated mile display: granularity. 1/250 < 1/100.

 

[bonaire]

Using EVtripper.com driving 100 miles with a net elevation of 321ft in a MS 90D with an EPA range of 270 at
62mph uses 100RM and goes 270 miles on a full charge
74mph uses 120 and goes 225
81mph uses 134 and goes 201
89mph uses 150 and goes 180
96mph uses 167 and goes 162
111mph uses 207 and goes 130

The large drop of in range isn't particular to electric cars. It's just physics.

democappy getting 180 miles of range seems about right given his driving style

As batteries are used "harder", they warm. Warmer batteries have higher Internal Resistance (IR). And all the rest is downhill in terms of "range at higher speeds". The price you pay for driving fast is lower range. A 20mpg car at 55mph will get 14mpg at 100 mph or more. Nothing different there.

 

[bak_phy]

As batteries are used "harder", they warm. Warmer batteries have higher Internal Resistance (IR). And all the rest is downhill in terms of "range at higher speeds". The price you pay for driving fast is lower range. A 20mpg car at 55mph will get 14mpg at 100 mph or more. Nothing different there.

This has nothing at all to do with the battery. It's just air resistance which increase as velocity to the 3rd power meaning that you need extra energy to get somewhere proportional to velocity squared.

 

[Canuck]

Nav will display estimated battery percentage upon arrival whether you have the gauge set to display battery percentage or rated mileage, so that's not really relevant to this discussion.

I know it estimates percentages on arrival, that's why it's very relevant -- and makes it easier -- to have your battery display in percentage rather than miles.

 

[RAW84]

I know it estimates percentages on arrival, that's why it's very relevant -- and makes it easier -- to have your battery display in percentage rather than miles.

What, exactly, is it making easier?

 

[msnow]

I know it estimates percentages on arrival, that's why it's very relevant -- and makes it easier -- to have your battery display in percentage rather than miles.

I think it's really the best of both worlds if you have the granularity of the miles or km on the IC and the percentage on the Nav map. If the expressway signs shows "x kilometers" to Abbotsford and you have 5% "in the tank" you know with more precision if you will make it.
<notice how I localized that for you?>

 

[RAW84]

One thing Tesla could do to provide a more "realistic" estimate of range is to allow the user to adjust the Wh/mi that results in actual mileage equaling the rated miles. Display it in a different color so it's immediately clear that the gauge is displaying rated range that's not per the mfg's spec.

 

[Trunk Gap]

To the soapbox guy talking about the dangers of 80+, go away. This isnt a thread for you to preach to people who arent interested in the projection of your own insecurities. No thanks, nothing more from me on it.

This is a very useful discussion, thanks folks. A in terms of understanding how this all works and B I will adjust to past 30 miles and see how that changes things in terms of a more realistic range. I just want the little battery on the dash to be realistic thats all. I dont want to mess w energy apps and analyze stuff, just want the car to say "hey dude you pretty much drive 80+ on every highway you touch, so buddy you're in for 1xx miles of range in reality, sorry pal" - preferably with a british accent. Not really, but you know what I mean, just want the battery to be realistic.

 

[JimmyMcNulty]

If I charge my MS to full (270 miles), I still only get...maybe 180 miles, even on the highway (although I do drive fast so imagine driving briskly, not flooring it everywhere, but I do like to maintain a fast speed/80+ on mexican highways). Is this normal?

Also, is there a way to get the battery indicator to be more real based on my actual driving? I dont want to get in the car and have it say 270, when I know after i drive 30 miles its going to be at 210.

Just wanted to congratulate you on the awesome username, fellow Lock, Stock and Two Smoking Barrels fan.

And I agree on the need for a more accurate range estimate.

 

[msnow]

To the soapbox guy talking about the dangers of 80+, go away. This isnt a thread for you to preach to people who arent interested in the projection of your own insecurities. No thanks, nothing more from me on it.

This is a very useful discussion, thanks folks. A in terms of understanding how this all works and B I will adjust to past 30 miles and see how that changes things in terms of a more realistic range. I just want the little battery on the dash to be realistic thats all. I dont want to mess w energy apps and analyze stuff, just want the car to say "hey dude you pretty much drive 80+ on every highway you touch, so buddy you're in for 1xx miles of range in reality, sorry pal" - preferably with a british accent. Not really, but you know what I mean, just want the battery to be realistic.

Lol, you don't have to "analyze" anything. It's just there. There's no way to change the battery display except rated, ideal or percent. That's all.