SCW-Greg
Active Member
When I've been low on gas from a long trek, I'll draft semi trucks (you can do that at a safe distance), and it makes a big difference.
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Motor Trend: World Exclusive! 2012 Tesla Model S Test and Range Verification
- Thread starter FalconNinetyD
- Start date
When I've been low on gas from a long trek, I'll draft semi trucks (you can do that at a safe distance), and it makes a big difference.
When talking about range, remember that it has been reported that the 21" wheels and tires have a 2% range penalty over the 19s, it is unknown how much of that is aero, and how much is rolling resistance.
I conjured up a spreadsheet based on the Roadster spreadsheet from the blog post and it led me to believe that the now-unavailable aerodynamic wheels would provide a 7% boost at 70mph ( based on calculations assuming a 5% boost at 55mph )
We now have a real world datapoint of a range test of 21 inch wheels and sticky performance tires.
We need to see real world tests of some "normal tires" and some LRR tires - on 19 and 21 inch wheels - and the return of an aerodynamic wheel option.
I conjured up a spreadsheet based on the Roadster spreadsheet from the blog post and it led me to believe that the now-unavailable aerodynamic wheels would provide a 7% boost at 70mph ( based on calculations assuming a 5% boost at 55mph )
We now have a real world datapoint of a range test of 21 inch wheels and sticky performance tires.
We need to see real world tests of some "normal tires" and some LRR tires - on 19 and 21 inch wheels - and the return of an aerodynamic wheel option.
http://www.youtube.com/watch?v=lttgT1XZVvE
150 feet is safe distance at 55. 100 feet offers ~10% improvement. 50 feet is 20% improvement.
STxTesla
Sig #1278
Contaygious....you're right...lol....too fast and fun for the right lane.
Some of the things that people might be forgetting:
1. This is first edition of the Model S.
2. The battery was apparently designed to be easily swapped. (I read into this feature...upgradability).
3. Battery technology is improving each year. (Improving range on existing cars by replacing some of the cells/rows in the battery pack
with newer battery technology may make range improvement upgrades affordable...must admit this is a big guess).
4. Long trips are not impossible...they just include more stops. (For every 1,000 miles traveled...maybe two more stops than a gasser?)
5. The Tesla Model S is a great car and we tend to nitpick the car to death. We sometimes forget to thank Tesla Motors for providing us
with a non-petroleum option NOW that may have otherwise taken another 10-20 years to finally become available.
In my opinion...the 11% variance in the Motor Trend results from EPA ratings is negligible. (I live in a flat part of Texas though...so if you
live in a hill covered countryside area I can understand your concern). I believe that we have a great car coming to us that will change the
way that America thinks about driving electric cars and I am proud to be one of the early adopters.
Some of the things that people might be forgetting:
1. This is first edition of the Model S.
2. The battery was apparently designed to be easily swapped. (I read into this feature...upgradability).
3. Battery technology is improving each year. (Improving range on existing cars by replacing some of the cells/rows in the battery pack
with newer battery technology may make range improvement upgrades affordable...must admit this is a big guess).
4. Long trips are not impossible...they just include more stops. (For every 1,000 miles traveled...maybe two more stops than a gasser?)
5. The Tesla Model S is a great car and we tend to nitpick the car to death. We sometimes forget to thank Tesla Motors for providing us
with a non-petroleum option NOW that may have otherwise taken another 10-20 years to finally become available.
In my opinion...the 11% variance in the Motor Trend results from EPA ratings is negligible. (I live in a flat part of Texas though...so if you
live in a hill covered countryside area I can understand your concern). I believe that we have a great car coming to us that will change the
way that America thinks about driving electric cars and I am proud to be one of the early adopters.
CapitalistOppressor
Active Member
Drafting is not going to take you 200 miles. Drop your speed by 5mph and it adds 20 miles to your notional range. So if they had averaged 60mph and turned on the A/C they likely would have ended with the same 240 mile range they achieved doing 65 with the vent. Doing that would add ~20 minutes to their trip. Or, if there is a SuperCharger available you can just do 80 with the A/C and stop for 20 minutes to give yourself a booster charge.
Regardless, for around town driving there is no range anxiety whatsoever. Leaf and other EV's force you to drive conservatively during normal driving, as opposed to just a few times a year with the Model S where you can be conservative, or stop at a charger more than you would have to in a gas powered car.
For me, Los Angeles to Vegas is the main road trip I take, and based on this testing I expect no change in my lifestyle. I always stop in either Barstow or Baker for a quick bite and/or bathroom break. I fully expect Tesla to implement a SuperCharger in Barstow, but there are conventional charge points there until they do, and even they are probably good enough to give me what I need with an hour stop.
That happens twice a year, while outside of that I can drive like a maniac with a clean conscious
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Driving from Fontana to San Diego is a fairly mountainous trip. Not like doing the Grapevine, but most folks East of the Rockies would think they were substantial mountains. Probably thats why their range looked terrible until they came down into San Diego. That last stretch heading into the city is a huge regen opportunity.
Regardless, for around town driving there is no range anxiety whatsoever. Leaf and other EV's force you to drive conservatively during normal driving, as opposed to just a few times a year with the Model S where you can be conservative, or stop at a charger more than you would have to in a gas powered car.
For me, Los Angeles to Vegas is the main road trip I take, and based on this testing I expect no change in my lifestyle. I always stop in either Barstow or Baker for a quick bite and/or bathroom break. I fully expect Tesla to implement a SuperCharger in Barstow, but there are conventional charge points there until they do, and even they are probably good enough to give me what I need with an hour stop.
That happens twice a year, while outside of that I can drive like a maniac with a clean conscious
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Driving from Fontana to San Diego is a fairly mountainous trip. Not like doing the Grapevine, but most folks East of the Rockies would think they were substantial mountains. Probably thats why their range looked terrible until they came down into San Diego. That last stretch heading into the city is a huge regen opportunity.
Elon's car doesn't have the spoiler, so no impact from that. I think it's unreasonable for a motor mag to drive it like a hypermiler; they know the vast majority of their readership wouldn't, and they'd get called out for it. They dont try to drive ICE cars for maximum mileage, so why make an exception for an EV? They've driven it in a reasonably normal fashion (I.e. how many people would drive it over that kind of distance, once the novelty of the acceleration has worn off) and got decent results. Of course they could be better, but it seems to be fairly "real world", and something most can relate to. I think it's a good result for the Model S, personally.
goyogi
Member
Love this photo of a person taking a picture of the S. Will we see it on the random sightings thread?
Yes, but you also go further. Power per unit distance goes up by the square of the velocity.
These were people who don't know how to drive the vehicle. Even one turn around their "test track" might have sucked a lot of power. And it might not have been completely full to start. And we know it wasn't empty at the end. There's not enough information in the article to get depressed.
The MT article has really been a wake up call for me. Planning a road trip that is about 1,450 miles each way (2,900 round-trip) when I get my Model S (hopefully in November) requires a lot of assumptions. After this article, realizing it is only one test and not necessarily indicative of what my trip will be like, I've adjusted some assumptions as listed here:
[1] Ideal range by speed per the Tesla Motors website blog: http://www.teslamotors.com/blog/model-s-efficiency-and-range; 60mph gives you about 275mi. range
[2] 10% energy loss - due to extra passenger (total weight w/luggage 400+ lbs.); assumed wind conditions; some climate control (colder in November - start in Chicago)
[3] Charging station power draw - 8 amps less than max current - i.e., 30-amp J1772 - the Model S will draw 22 amps; 50-amp NEMA 14-50 (RV) - the Model S will draw 42 amps (based on experience with early model Roadster); not sure what the Model S is actually capable of here
[4] 240V AC Charging stations (J1772 and 50-amp RV service) - this is used to measure approximate charging power
[5] 10% assumed time loss - pit stops, etc. (i.e., 120 mi. at 60 mph takes you 2.2 hours and not 2.0 hours)
[6] Hotels for overnight stays will be within a few miles (or less) of RV parks (when charging in RV parks at night - cannot sleep in the car); will need to take a small fold-up bike to transport self to and from the car at the RV park to the hotel after dropping off the wife and luggage at the nearby hotel, of course! (the bike will need a pretty bright night light); fold-up bike will go in the Frunk
[7] Daytime charging stations will be within walking distance of places to eat or shop or get the internet (do work, surf the web, etc.) or go to a movie (will need to kill a few hours or more while charging)
[8] Range cushion = 5 miles; that is, with conservative assumptions above (hopefully they are conservative); charging range needs to be at least 5 miles greater than next destination.
For a successfull road trip (i.e., get there in the designated time - that is get there without needing a tow), the real-world conditions would all need to meet or exceed these assumptions. There is one tricky part of the trip that would require 240 miles between stopping points in OK and TX. I would need to do hyper-miling, most likely in some fashion to make it (if all else fails I can find a 120V outlet but that adds time to an already estimated 12 hr day of driving/charging).
With travel, day-time charing, overnight stays (and overnight charging), and enjoying the Thanksgiving Holidays with relatives (assuming I get the car before then), the total trip time is 10 days. I have a spreadsheet for this but didn't want to clog the airwaves with it, so I've listed the assumptions above.
Any thoughts? Too conservative or not conservative enough?
[1] Ideal range by speed per the Tesla Motors website blog: http://www.teslamotors.com/blog/model-s-efficiency-and-range; 60mph gives you about 275mi. range
[2] 10% energy loss - due to extra passenger (total weight w/luggage 400+ lbs.); assumed wind conditions; some climate control (colder in November - start in Chicago)
[3] Charging station power draw - 8 amps less than max current - i.e., 30-amp J1772 - the Model S will draw 22 amps; 50-amp NEMA 14-50 (RV) - the Model S will draw 42 amps (based on experience with early model Roadster); not sure what the Model S is actually capable of here
[4] 240V AC Charging stations (J1772 and 50-amp RV service) - this is used to measure approximate charging power
[5] 10% assumed time loss - pit stops, etc. (i.e., 120 mi. at 60 mph takes you 2.2 hours and not 2.0 hours)
[6] Hotels for overnight stays will be within a few miles (or less) of RV parks (when charging in RV parks at night - cannot sleep in the car); will need to take a small fold-up bike to transport self to and from the car at the RV park to the hotel after dropping off the wife and luggage at the nearby hotel, of course! (the bike will need a pretty bright night light); fold-up bike will go in the Frunk
[7] Daytime charging stations will be within walking distance of places to eat or shop or get the internet (do work, surf the web, etc.) or go to a movie (will need to kill a few hours or more while charging)
[8] Range cushion = 5 miles; that is, with conservative assumptions above (hopefully they are conservative); charging range needs to be at least 5 miles greater than next destination.
For a successfull road trip (i.e., get there in the designated time - that is get there without needing a tow), the real-world conditions would all need to meet or exceed these assumptions. There is one tricky part of the trip that would require 240 miles between stopping points in OK and TX. I would need to do hyper-miling, most likely in some fashion to make it (if all else fails I can find a 120V outlet but that adds time to an already estimated 12 hr day of driving/charging).
With travel, day-time charing, overnight stays (and overnight charging), and enjoying the Thanksgiving Holidays with relatives (assuming I get the car before then), the total trip time is 10 days. I have a spreadsheet for this but didn't want to clog the airwaves with it, so I've listed the assumptions above.
Any thoughts? Too conservative or not conservative enough?
I'm actually quite impressed by the range these guys got. Remember they did not drive the car till it stopped. The display indicated 4 miles remaining when they quit their drive. It is reasonable to assume that Tesla built in a buffer on the display so people don't run out, meaning there were actually more than 4 miles remaining, like when the gas gauge on your ICE shows empty you've actually got a few more miles. My Leaf does this--when it tells you there are 9 miles to go in fact you've got another 15 miles easy.
The Motor Trend guys used 78.2 KWH to go 233.7 miles. Using up the entire 85 KWH equates to (233.7/78.2)*85 = 254.0 miles to empty. Given that this was not flat terrain, that there were headwinds at times, that the performance tires shaved off a few percent range and that these guys were inexperienced EV drivers not going out of their way to stretch the range, I think their results are fantastic and right in line with the EPA figures.
If you want to max out the range on an EV when you need to it's not that hard to do. (Primarily just slow down.) If you have not driven an EV as a primary car yet please don't get spooked by the Motor Trend range numbers. All is well.
The Motor Trend guys used 78.2 KWH to go 233.7 miles. Using up the entire 85 KWH equates to (233.7/78.2)*85 = 254.0 miles to empty. Given that this was not flat terrain, that there were headwinds at times, that the performance tires shaved off a few percent range and that these guys were inexperienced EV drivers not going out of their way to stretch the range, I think their results are fantastic and right in line with the EPA figures.
If you want to max out the range on an EV when you need to it's not that hard to do. (Primarily just slow down.) If you have not driven an EV as a primary car yet please don't get spooked by the Motor Trend range numbers. All is well.
They specifically said that they called Tesla and asked what happened when the range got to zero, and were told that the car stopped. So, if there is a buffer, they got bad info.
That being said, I will certainly look forward to hearing what sort of range experienced EV drivers get.
The way my Leaf works is it sticks on 9 miles to go for multiple miles. I'm not suggesting when Model S says 0 it does not mean 0, rather that when it shows a low enough single digit of miles left that there may really be more miles remaining than displayed. How does your RAV4 EV handle it?
Edit: What I'm suggesting is that the miles remaining display on Model S may not be linear once it displays single digits just as it is not linear on the Leaf and as many ICE gas gauges are not linear as they approach empty.
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The RAV doesn't display range per se. It has a straightforward SOC gauge that looks like a gas gauge (analog), with 8 green bars, a yellow and a red. The bottom of the green arc is about 20% SOC. The bottom of the yellow is about 15% SOC.
When you hit the top of the yellow, a little amber fuel pump light comes on. When you hit the bottom of the yellow, that light starts to flash.
The gauge actually goes below the bottom of the red (the needle's stop point is not set at the bottom of the graphic). I think the bottom of the red is about 5% SOC. If you drive to the bottom of the gauge, then if you try to draw significant current from the pack, the BMS will begin to limit power to keep the module voltage from dropping below a minimum threshold, and you get a little yellow turtle icon lighting up, indicating reduced performance. The car will basically drive until it just can't go anymore. I have never done that, because it's not good for it.
If your pack is unbalanced, the car may not let you get to the bottom of the gauge, because one module's voltage will fall into danger territory before overall pack SOC reaches the bottom.
So, my rule of thumb is: if I'm driving very conservatively, each bar on the SOC gauge is 10 miles. If I'm driving normally, they're 8 miles. If I'm driving fast (70+) or it's very hilly, they can be 6 per bar. But, the car is very linear in how it uses power, so I can keep an eye on the gauge and see how far I've gone over one bar, and that will predict very accurately how it will perform through the rest of the range. I also use a Palm Pilot connected to the OBD-II port to give me precise SOC numbers, as well as current draw, which are helpful for trying to really maximize range. The Model S instrumentation seems to have all this information.
When you hit the top of the yellow, a little amber fuel pump light comes on. When you hit the bottom of the yellow, that light starts to flash.
The gauge actually goes below the bottom of the red (the needle's stop point is not set at the bottom of the graphic). I think the bottom of the red is about 5% SOC. If you drive to the bottom of the gauge, then if you try to draw significant current from the pack, the BMS will begin to limit power to keep the module voltage from dropping below a minimum threshold, and you get a little yellow turtle icon lighting up, indicating reduced performance. The car will basically drive until it just can't go anymore. I have never done that, because it's not good for it.
If your pack is unbalanced, the car may not let you get to the bottom of the gauge, because one module's voltage will fall into danger territory before overall pack SOC reaches the bottom.
So, my rule of thumb is: if I'm driving very conservatively, each bar on the SOC gauge is 10 miles. If I'm driving normally, they're 8 miles. If I'm driving fast (70+) or it's very hilly, they can be 6 per bar. But, the car is very linear in how it uses power, so I can keep an eye on the gauge and see how far I've gone over one bar, and that will predict very accurately how it will perform through the rest of the range. I also use a Palm Pilot connected to the OBD-II port to give me precise SOC numbers, as well as current draw, which are helpful for trying to really maximize range. The Model S instrumentation seems to have all this information.
Yeah. Why not just rent a car for that road trip? I'm assuming this is something you do irregularly. Why put nearly 3000 miles on your Model S in just a few days? Unless you just want to do this with the Model S for the pride and adventure of it all.
My thoughts on the MT range test (some repeated points here from earlier):
1. Route is not level as others have mentioned, especially I15.
2. 21" wheels + Michelin Pilot PS2 sports - who knows what the rolling resistance of these are compared to the spec tires.
3. Is Elon's car also wearing 265 width tires in the rear as the Edmunds test car was?
4. What wheel/tires are the EPA numbers based on?
5. The 78.2 kWh - doesn't mean much unless we know if it's the reading from the car itself or if it's wall-to-wheel numbers. I suspect the 78.2 kWh is from the car.
6. How far does the car really go once the DTE reaches zero?
1. Route is not level as others have mentioned, especially I15.
2. 21" wheels + Michelin Pilot PS2 sports - who knows what the rolling resistance of these are compared to the spec tires.
3. Is Elon's car also wearing 265 width tires in the rear as the Edmunds test car was?
4. What wheel/tires are the EPA numbers based on?
5. The 78.2 kWh - doesn't mean much unless we know if it's the reading from the car itself or if it's wall-to-wheel numbers. I suspect the 78.2 kWh is from the car.
6. How far does the car really go once the DTE reaches zero?
Surprisingly, yes it is. One of the Prius group members mounted an anemometer and found that there was significant reduction at two seconds. That's closer than I like to follow but it's further away then most people normally travel.
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Spending $80K+ on a car and having to rent one to do normal driving, and vacation trips are normal driving, is just wrong on so many levels.
That would be quite an adventure but sounds like you're up for it. I'm not sure about #3. The car draws 30A on a 40A J1772 charger (32A would be 80% of 40A but the plug is only rated at 30A) and 40A on a 50AM NEMA 14-50 outlet I thought.
Todd Burch
14-Year Member
Florida is flat. California is not. You should be able to hit 200 miles no problem, even with A/C blasting.