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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

#101

Post by taneq »

pbreit wrote: post #42
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…

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 economy on the highway because they have no regen braking and their engines are more fuel efficient at highway speeds.

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

#102

Post by davidwhodge »

new_realist wrote: post #12
tenpies wrote: post #6

I'll wait for Consumer Reports or the EPA before believing any of Tesla's range claims. E: As in from the EPA itself and validated by Consumer Report's field-testing, not Tesla claiming EPA certification and verified through easily cheat-able testing.

Teslas are known for achieving only 75-85% of EPA in the real world. This is based on my own data, owning multiple Teslas over four years. The issue is that short drives suffer HVAC losses and long drives are at highway speeds, which is significantly above the speed the EPA uses for their dyno. tests. Further, Tesla actually runs the tests themselves and uses their own calculations to simulate wind resistance.

I cover this a bit in my post about the data I've seen in the 1000+ Tesla fleet that I track with Nikola. 75-85% is about I right.

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

#103

Post by laurencerowe »

sgc wrote: post #51
elihu wrote: post #40

They mention "significant weight reduction" but don't mention how much weight they saved. Considering how heavy Model S's are, this seems like it could be a productive approach, though on the other hand if there were easy/obvious ways to reduce unnecessary weight, it would have been done by now. On some level it's a trade-off between being too heavy and being unsafe, though reducing the weight also means it doesn't h…

yes and no. Older cars were far heavier and far less safe. They could make incremental safety design improvements that allow to reduce weight incrementally without compromise.

I’m not sure whether you mean older teslas or older cars generally here. Small cars in the 70s and 80s weighed just over half as much as they do now. The Golf Mk 1 was 795kg while a Mk 8 is 1255kg. Much of that increase in weight is safety equipment and they are much safer for it.

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

#104

Post by anonymousiam »

jodrellblank wrote: post #79
anonymousiam wrote: post #57

They are lying. I was in the market for a new car earlier this year, and I really wanted to get a Tesla. I also really wanted a car that could handle a trip of 295 miles that I regularly make. I will not go into the nightmare that was scheduling a test drive of the long-range Model S, but after getting conflicting answers from multiple PoCs at Tesla, I finally got the firm answer. The car cannot do even my 295 mile c…

The BMW i3 has had the perfect electric car design for the last 7+ years - a battery pack good for ~50-120 miles (increased with model revisions) and a gasoline generator "range extender" with a small tank for indefinite length journeys hopping between standard gas stations - which are abundant. It improves on hybrid-car designs: the engine isn't connected to the drive train, so it's a lot less complex, and the engin…

I really liked the i7, and I would have liked to stay with the BMW brand, but the poor thing had a 100 mile range. It certainly looked good, but it was even less practical than what I had.

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

#105

Post by davidwhodge »

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…

Another fun fact on practical drain vs. EPA drain:

While I love sentry mode and think it's a great feature, it keeps the electronics awake. In some cases this can cause double digit per day mileage drain. Tesla has clearly been working on this though, as the numbers have improved.

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

#106

Post by dannyw »

anonymousiam wrote: post #93
rcMgD2BwE72F wrote: post #78

Earlier quoted context omitted.

Charge to 95% from home so you'd only have to stop for a few minutes. That is highly recommended for your safety anyway.

My point is that with a 100% charge from driveway to driveway, My 295 mile trip would still require a stop for a 20 minute charge (not counting all of the logistics associated with that). As posted elsewhere in this thread, http://www.tesla.com/trips is still reporting the exact same numbers it was in January when I gave up and bought my new car.

It's quite possible tesla.com/trips haven't updated yet.

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

#107

Post by rowawey »

tenpies wrote: post #6

I'll wait for Consumer Reports or the EPA before believing any of Tesla's range claims. E: As in from the EPA itself and validated by Consumer Report's field-testing, not Tesla claiming EPA certification and verified through easily cheat-able testing.

I wouldn't hold my breath, CR is a husk of its former self and doesn't produce very much content anymore.

The main numbers that matter are:

- conversion efficiency of converters/inverters, if any

- efficiency of motors

- drivetrain friction

- tires' rolling resistance

- tires' air pressures

- wheels' alignment

- rotational moment of wheels (possibly)

- total weight

- coefficient of drag

which lead to kWh/mi or kWh/km, combined with usable kWh, results in range.

There's no cheating measured data or fundamental principles.

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

#108

Post by cwhiz »

anonymousiam wrote: post #80
cwhiz wrote: post #71

Earlier quoted context omitted.

Consumer Reports was able to get 355 miles in the Model S Long Range at 65mph. They were able to get 418 miles at 55mph. I would expect the Long Range Plus to be about 10% better based on all of the CR data. I am not sure where you got that information from Tesla but I trust that CR wasn’t just making shit up.

Tesla directed me to their trip planning application: https://www.tesla.com/trips . I just ran it again with the "Model S Long Range" selected, and my 295 mile trip requires a 20 minute charge in Baker, CA.

Their trip planner recommends a charge in the middle for almost any trip greater than 200 miles. I am not sure why.

It also could just be a fairly hilly drive or a drive with a high speed limit. Either way it’s pretty unfair to say Tesla is outright lying because the stated range isn’t applicable to every possible stretch of road in the world.

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

#109

Post by satvikpendem »

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…

Looks like the purported range is analogous to stated phone or laptop battery life: ideal and unrealistic. This makes sense because the car is, in fact, run by a battery.

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

#110

Post by chongli »

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…

For the hundreds of Nikola trips with an average speed of 60 mph, the actual MPGe was about 102. Once you get up to an 75 MPH average trip speed, the MPGe drops to 94. And by 80 MPH the MPGe drops to 77. (avg over all Tesla types)

That makes total sense. What I think most people don’t realize is that power is force times velocity and the force you need to apply to maintain a given velocity is equal to the friction plus the drag. Unfortunately, drag increases with the square of the velocity and so when you go faster you need way more power. This translates directly into increased battery drain for an EV.

The problem may be further exacerbated by the greatly increased mass of an electric vehicle and the potential for the batteries to overheat.

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