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Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

tesla.com

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Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#211

Post by thdrdt »

taneq wrote: post #101
pbreit wrote: post #42

Earlier quoted context omitted.

Teslas are designed to perform better (and EPA is designed to evaluate) NOT on freeways (ie, where most people drive)(mainly due to very good regenerative braking).

All cars perform better (in terms of kWh through the driveshaft per km) at lower speed, since air resistance rises quickly with speed. Tesla can't do anything to change this, although they do try to mitigate it with good aero. Electric cars can regen brake and so recover some energy in stop/go traffic, but they're still more efficient at constant low speed than stop/go at low speed. ICE vehicles only get better econo…

This is not complete true. Most combustion cars perform best around 90km/h. Below that speed air resistance is not much of an issue but gears help a lot getting the best performance out of the engine.

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#212

Post by Faaak »

softgrow wrote: post #184

Can we have an EV for people who don't suffer from range anxiety and are willing to trade that off for cost? I travel 5000km (3000mi) a year, longest single day use 50km (30mi). Vehicle is garaged with access to power. I just need 100km (60mi) (double to be sure :) ) range at an affordable cost.

There are already plenty.

The Renault Twizy would be perfect for you

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#213

Post by ngngngng »

rossjudson wrote: post #181
leesec wrote: post #122

Man do I love Hackernews. Everyone is pro-innovation, pro-future, pro-forward thinking until literally anything new happens, in which case everyone shows up with a "well, ackshually", to tell you why the new idea is dumb. It's amazing to me that Tesla continues to increase State Of The Art range and EV efficiency, at scale, for cars that already smoke the competition. I hope their fervor to improve the technology nev…

"Nobody is going to buy this thing. I commute 250 miles each way to my job, in my pickup truck. Call me back when Tesla makes a real car with real range. Anybody who buys these now is a sucker." Because people keep saying shit like that. Tesla's range increases are a giant experiment to find out at exactly what point opposition to electric collapses.

I heard a similar argument when I expressed to in an online community that I was going to pre order a cyber truck.

"That thing can only two 14,000 lbs. No ones going to buy a truck that can only two that much, my F350 can tow 20,000 lbs, that's much more useful."

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#214

Post by reitzensteinm »

natch wrote: post #205
reitzensteinm wrote: post #147

Earlier quoted context omitted.

"Manufacturers test their own vehicles—usually pre-production prototypes—and report the results to EPA. EPA reviews the results and confirms about 15%–20% of them through their own tests at the National Vehicles and Fuel Emissions Laboratory.[6]" https://en.wikipedia.org/wiki/Electric_car_EPA_fuel_economy

Quoting Wikipedia as evidence, nice. Actually in the recent Model S test prior to this one, Tesla discovered through examination of the data logs of the car that the EPA had carelessly left the key in the car all night while it was parked during testing that spanned multiple days, leading to an artificially low number as the car was unable to sleep at the level it normally should be able to when parked. This whole ep…

OK, fair point. Allow me to quote from the EPA directly. [1]

"Manufacturers test their own vehicles—usually pre-production prototypes—and report the results to EPA. EPA reviews the results and confirms about 15%–20% of them through their own tests at the National Vehicles and Fuel Emissions Laboratory."

Wait a minute...

[1] https://www.fueleconomy.gov/feg/how_tested.shtml

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#215

Post by radium3d »

steelframe wrote: post #18

I've been following a multi-month discussion over in the r/electricvehicles subreddit about EPA range. There's a growing consensus that something is very wrong with it. Here are a couple of the articles that got some discussion in that sub: https://insideevs.com/news/407807/eletric-car-real-world-ran... https://www.caranddriver.com/reviews/a30874032/porsche-tayca... As someone who has owned both a Tesla Model X and o…

My Tesla Model 3 SR+ tends to exceed the EPA rating on most trips, but the Model S loaners I've had have been quite a bit more thirsty and varied greatly, although I couldn't help but play with all the extra power they have. Still blows the pants off anything else as far as efficiency.

I've made a spreadsheet to compare the energy usage of my 2019 3 SR+ to my old 2014 Subaru Crosstrek Hybrid: https://docs.google.com/spreadsheets/d/16JLSzoWA0154ZUU3ahJ_...

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#216

Post by octorian »

rossjudson wrote: post #181
leesec wrote: post #122

Man do I love Hackernews. Everyone is pro-innovation, pro-future, pro-forward thinking until literally anything new happens, in which case everyone shows up with a "well, ackshually", to tell you why the new idea is dumb. It's amazing to me that Tesla continues to increase State Of The Art range and EV efficiency, at scale, for cars that already smoke the competition. I hope their fervor to improve the technology nev…

"Nobody is going to buy this thing. I commute 250 miles each way to my job, in my pickup truck. Call me back when Tesla makes a real car with real range. Anybody who buys these now is a sucker." Because people keep saying shit like that. Tesla's range increases are a giant experiment to find out at exactly what point opposition to electric collapses.

"Nobody is going to buy this thing. I commute 250 miles each way to my job, in my pickup truck, hauling a load of lumber to a cabin 100 miles from civilization. There's no electricity out there. Call me back when Tesla makes a real car with real range. Anybody who buys these now is a sucker."

FTFY.

There's one of these in EVERY discussion of something Tesla releases :-)

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#217

Post by m463 »

davidwhodge wrote: post #92
steelframe wrote: post #18

I've been following a multi-month discussion over in the r/electricvehicles subreddit about EPA range. There's a growing consensus that something is very wrong with it. Here are a couple of the articles that got some discussion in that sub: https://insideevs.com/news/407807/eletric-car-real-world-ran... https://www.caranddriver.com/reviews/a30874032/porsche-tayca... As someone who has owned both a Tesla Model X and o…

I make an app (called Nikola, not the truck company) for Tesla owners that has seen over 5 MM miles driven on it. I did some quick queries to validate actual range vs. EPA range for those curious. My general takeaway is to see the EPA range as a useful, albeit unrealistic, indicator. Essentially nobody gets the EPA range, either because they choose not to go the speed limit, they accelerate harder than the EPA test f…

I'm surprised tesla doesn't break down energy usage visually.

The nissan leaf has an energy usage display that breaks down energy into driving, climate and other systems.

http://www.nissanusa.com/vlp-assets/media/vehicles/2016/leaf...

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#218

Post by octorian »

kylecordes wrote: post #157

It's great that Tesla keeps increasing the range, but the EPA numbers are ridiculous. I would love to see the EPA range claims for electric vehicles re-standardized to measure: * at the median driving speed on free-flowing US interstate highways * during cold weather * with some hills * using a medium level typical of drivers of cars of the price range A car manufacturer particularly focused on realism could publish…

> the EPA numbers are ridiculous

If you think that, you should look at the NEDC numbers they post in Europe :-)

Okay, tried to dig those up and they've apparently switched to the WLTP standard there. That's good, because the NEDC numbers tended to be massively inflated.

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#219

Post by avs733 »

burlesona wrote: post #178
kylecordes wrote: post #157

It's great that Tesla keeps increasing the range, but the EPA numbers are ridiculous. I would love to see the EPA range claims for electric vehicles re-standardized to measure: * at the median driving speed on free-flowing US interstate highways * during cold weather * with some hills * using a medium level typical of drivers of cars of the price range A car manufacturer particularly focused on realism could publish…

The EPA tests are interesting. They do simulate stop and go driving, and that’s why on a gas car the city number is worse, but the steadier highway test shows better numbers. One of the weird things with an EV is that the highway numbers are actually worse (as other posters have commented). The tests definitely trade off realism for consistent reproducibility though. This article describes it in detail, it’s really i…

I was going to write something longer and then got distracted and this thread went bonkers, so sadly your post is not going to get the attention it deserves.

I've actually toured a fuel economy lab for a Tier I/Big 3 auto manufacturer. The testing procedures described there are correct...account for as many variables as possible. The lab I toured had the dynos in temperature and humidity controlled rooms. Exhaust vents were standardized in length to ensure consistency, etc.

MPG is serious business with millions on the line.

Most interesting story I had was that they have several drivers they use for different purposes. Some are super consistent and used for repeatability tests. Others specialize in maximizing mileage. They quoted a 5% improvement by certain drivers over others on the SAME TEST. which already has incredibly precise time/speed windows that the drivers must stay in between. Every time, someone is manually controlling the throttle and brake pedal. Although they can use a computerized control for other testing.

They will run the test until they get the best possible test and then ship that to the EPA.

Re: Model S Long Range Plus: Building the First 400-Mile Electric Vehicle

#220

Post by avs733 »

kenhwang wrote: post #197
burlesona wrote: post #178

Earlier quoted context omitted.

The EPA tests are interesting. They do simulate stop and go driving, and that’s why on a gas car the city number is worse, but the steadier highway test shows better numbers. One of the weird things with an EV is that the highway numbers are actually worse (as other posters have commented). The tests definitely trade off realism for consistent reproducibility though. This article describes it in detail, it’s really i…

The test is absolutely insane and it totally makes sense why EPA estimates can vary so much from real world numbers. It would practically ignore the effects of aerodynamics and I'm not even sure weight plays a role given both of those are supposedly accounted for by a simulated drag on the rollers.

weight is inertia and aero drag is a speed dependant force...both are just forces that can be simulated really easily on a dyno.
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