$35,000 Tesla Model 3 confirmed - Preorder opens in March

Tesla need to get these new models established quickly with minimal problems in production or delivery etc.
The competition is coming fast...
....Audi is expected to show an all-electric crossover concept at next month's Frankfurt Motor Show, and this week the company revealed that the eventual production EV will boast a 310-mile (500-km)-range battery built on cells from LG Chem and Samsung SDI. That battery will be integrated neatly into its new MLB platform, which will be dressed in new design language.

Audi spoke of plans to launch a 310-mile+ electric SUV at its annual press conference back in March.

"In early 2018, we will launch a battery-powered sports activity vehicle in the large premium segment with a range of more than 500 kilometers," Audi technical development board member Prof. Dr. Ulrich Hackenberg said at the conference.

That's almost certain to be an electric Q6 crossover seated cozily between the Q5 and Q7. It'll be built atop the newest iteration of MLB architecture debuted on the new Q7 and is expected to get its looks from the Prologue concepts that Audi's been parading around since last year's LA Auto Show.

Today, Audi revealed that the 2018 production model will reach the 310-mile goal using a battery pack developed from high-performance cell modules from LG Chem and Samsung SDI. The companies will supply Audi from their European production plants....
 
Since their $70,000 car is really $110,000 car once you get good battery, I don't believe that many will want their $35,000 car without options.

By the time you add in the decent battery, it will be $55,000, and it will be 3.5 years from now to really get one, and by then, it will have to compete against the 2019 Chevy Volt and whatever Audi offers for people who don't want a Chevy (although Chevy is making nice cars now as per the Impala, Cadillacs, and Stingray).

Tesla already gave out all their patents, and I predict that in five years, they will be a battery and component company competing with Samsung and Panasonic and supplying certain parts to other car companies.
 
The major automakers, seeing that Tesla is filling a market niche that the they could have filled in the 1990s, are now finally taking their shelved technology and putting it to use in a panic...

The only thing that's gotten noticeably better since the 1990s is batteries, and the low density batteries we had in the 1990s could give a well-designed car a 200 mile range, and the car could have cost under $30,000 in volume without subsidy. Do some reading on the Solectria Sunrise, for instance... 60 Wh/kg Ovonic NiMH batteries, and a real-world 200 mile range inside of a 27 kWh pack.

I'm glad that Tesla is getting somewhere. Nissan could have easily done it, but chose to emphasize styling on their Leaf, and not the load reduction that a streamlined form would bring. A 0.28 Cd and 250 Wh/mi is not very good, considering GM's EV1 could get by on 150 Wh/mi, and the 1921 Rumpler Tropfenwagen got a 0.27 Cd. Hell, even a modern Corvette comes in at a 0.28, and it's a f***ing musclecar of sorts... Guess what better wh/mi efficiency does to the cost per mile of range and the overall cost of the car itself? Drag coefficients of even as low as 0.15 are perfectly doable in a modern, practical EV, without adding to the cost or too heavily compromising consumer expectations. Imagine a 120 Wh/mi midsized sedan!

I am of the firm opinion that a sub $20,000, 150 mile range EV was doable 20 years ago, and an affordable 100 mile range EV was doable in the 1970s. The will on part of the automakers was simply lacking.

In 1998, Robert Stemple of GM quoted $150/kWh in volume for 20,000 cars per year for the Ovonic NiMH batteries, before Texaco got the patent and sat on it... before that, the McKee Sundancer and CdA towncars of the 1970s were built, getting highway speeds and 80 mile ranges on inexpensive golf cart components and flooded lead acid batteries.

Fortunately for EVs, lithium took over and exceeded NiMH's specs roughly a decade after the oilies kept it off the market, but lithium's volume cost hasn't come down until recently. Argonne National Laboratories did quote $250/kWh in automotive volume for Li-Ion-Co back in 2003, and now we are getting a similar cost today for a safer and more dense lithium chemistry... although most lithium batteries are still in the $500/kWh range. In purchase for one vehicle, my LiFePO4 in my electric GT6 came out to ~$400/kWh.

Tesla's Gigafactory is going to drive down battery costs further. Can you say $200/kWh? A $10,000 pack would give my GT6 a 400+ mile range, in theory... or 200 miles range in a Nissan Leaf.

The Model 3 is where we should have already been, in the 1990s, given what was possible then...
 
Nice summary, and sounds about right to me.

I had assumed the Leaf's awful looks were related to its function. From what you say, it seems that's not true: It's ugly and non-functional, with the aerodynamics of a wardrobe. If the designs were really going for "stylish" they need to go back to art college.
 
Not so easy to achieve (<0.28) drag efficiency and still have room for five people and a battery pack in a sub 30K car. The whole "looks thing" is very subjective, to me Tesla looks like a stepped on Viper. Once you learn of Leaf's "peculiarities", it is actually alright and at 45mPh it can go above and beyond its 100 miles. An ideal traffic car.
 
After state and fed incentives, $2K chevy incentives, $700 Costco prepaid card, my 2016 Volt cost 24K out the door (includes tax and CA licence).

With a electric range of 60+ miles on battery and a total 420 mile range on battery and gas, (gas milage is ~43 mpg) Tesla has a long way to go to make a car for the common driver.
 
sharkmobil said:
Not so easy to achieve (<0.28) drag efficiency and still have room for five people and a battery pack in a sub 30K car.

On the contrary, the entire auto industry is littered with prototypes from the 1920s onward that contradict this statement. The GM Precept(0.16 Cd), Ford Prodigy(0.2 Cd), and Dodge Intrepid ESX2(0.19 Cd) are all cars built by the Big 3 as prototypes whose shapes could have been used with conventional body materials and drive systems, instead of the exotic components used to get them to 80 mpg. A 3L V6 in something like that back in the mid 1990s could have easily exceeded 40 mpg hwy without the fancy new direct-injection engine technology and taller geared 7-speed transmissions we have now days. As an EV donor chassis with such aerodynamic efficiency, we'd be looking at cars that could do well under 180 Wh/mi on the highway, even if they were 4,000+ lb land yachts like the Tesla Model S.

The common excuse from the auto industry is "styling", or that no one will buy an ultra-aerodynamic car because it looks weird or all of the aerodynamic cars would look too similar. But looking at the GM Precept, Ford Prodigy, and Dodge Intrepid ESX3, they all looked quite normal for their time period, and there are plenty of concept cars and prototypes of the 1930-1950s that looked somewhat normal for their time period and radically different from the cars of today, that had significantly lower drag than the cars of today.

For many within the ecomodder community, getting an already existing mass-produced sedan or hatchback capable of seating 5 to get a Cd of under 0.2 is a matter of a few custom-built coroplast or fiberglass fittings. The rolling science projects may not look pretty, but they work very well and prove it can be done for cheap. If the car's body already came aerodynamic from the factory using conventional build materials to make these body pieces as opposed to ecomodders having to turn their vehicles into rolling science projects, these components could be made to look good enough to meet consumer expectations.

For a period, Tesla's Model S, commonly seen as a very good looking car, also had the lowest Cd of anything on the market at 0.24, until the highly limited production Volkswagen XL1 was made(0.19 Cd).

But then, by building cars as aerodynamic as possible, planned obsolescence would have to fall by the wayside. The average new automobile is just now catching up to the 1921 Rumpler in drag coefficient(New car average is 0.28 Cd, versus 0.27 for the Rumpler). The Rumpler could seat more than 5, and looked like it fit in its era as it doesn't look aerodynamic at all. The Tatra T77a, a large luxury sedan from 1935 that seats 7, had a Cd of 0.21. Compare those to the current generation Toyota Prius at 0.25 Cd, or Nissan Leaf at 0.28 Cd.

Batteries have gotten so dense that fitting them in virtually anything is a non-issue. I have a pack of almost 500 lbs in my tiny little Triumph GT6 which was NOT designed by Triumph to ever be an EV, while still maintaining the storage space it originally had. A car designed with the batteries built into the floor would have no issue fitting them at all as the Tesla Model S demonstrates.

In an EV, cost is mainly a function of production volume, at this moment.

Had the Leaf had half the drag coefficient it currently does, it would go almost twice as far on the same amount of battery, while not costing much more to build, if at all. The Solectria Sunrise was a 5 seat economy sedan that had a pack of similar kWh to the Leaf, and a 200 mile range, in 1996... and would have been under $20,000 in mass production according to its designer, James Worden. GM wouldn't touch it, and it stayed shelved.
 
When measured, there was substantial discrepancy in OEM Cd claims for most all makers (Honda, Mercedes etc), but Teslas Cd was spot on the OEM claims.
 
liveforphysics said:
When measured, there was substantial discrepancy in OEM Cd claims for most all makers (Honda, Mercedes etc), but Teslas Cd was spot on the OEM claims.

I've heard of this. Isn't this issue also partially why the SAE came up with a new standard of measuring this?

The Model S achieving a 0.24 is quite impressive given that it has made a lot of compromises to enhance styling. I am hoping that an "affordable" Tesla will have a 0.20 or less, just to maximize range per dollar spent.
 
Punx0r said:
Nice summary, and sounds about right to me.

I had assumed the Leaf's awful looks were related to its function. From what you say, it seems that's not true: It's ugly and non-functional, with the aerodynamics of a wardrobe. If the designs were really going for "stylish" they need to go back to art college.

It's a completely different market and its styling is related to function.

EV1 was a two seater mini-car with a height of just 1.283 metres. A car that low is never an option for the mass market.
Tesla Model S is 1.43 metres. The Model S isn't the easiest of cars to enter for older people.
Nissan Leaf is 1.55 metres. The perfect height for a large market of older people who have the largest amount of disposable income compared to other demographics. A lot of Leaf drivers are retired and they value ease of access.

The most prominent feature of the Leaf is the lights which are designed to aid airflow around the mirrors.
 
rsilvers said:
Since their $70,000 car is really $110,000 car once you get good battery, I don't believe that many will want their $35,000 car without options.

By the time you add in the decent battery, it will be $55,000, and it will be 3.5 years from now to really get one, and by then, it will have to compete against the 2019 Chevy Volt and whatever Audi offers for people who don't want a Chevy (although Chevy is making nice cars now as per the Impala, Cadillacs, and Stingray).

Tesla already gave out all their patents, and I predict that in five years, they will be a battery and component company competing with Samsung and Panasonic and supplying certain parts to other car companies.
No it is stated that 200+ (think its 250+) real world driving conditions of range will be in the $35,000 car. So that means you don't need to spend more for decent range.

I think the upgrades I will be interested in will be AWD and Performance.
 
Arlo1 said:
No it is stated that 200+ (think its 250+) real world driving conditions of range will be in the $35,000 car. So that means you don't need to spend more for decent range.

I think the upgrades I will be interested in will be AWD and Performance.

The rumour floating around on Tesla Motor's Club is that the base model will be 35k while AWD is supposed to be 40k.
 
All speculation. And at this point all we know is the base model is 35k. But its not unreasonable to think AWD will be 5k more.
 
Joseph C. said:
It's a completely different market and its styling is related to function.

EV1 was a two seater mini-car with a height of just 1.283 metres. A car that low is never an option for the mass market.
Tesla Model S is 1.43 metres. The Model S isn't the easiest of cars to enter for older people.
Nissan Leaf is 1.55 metres. The perfect height for a large market of older people who have the largest amount of disposable income compared to other demographics. A lot of Leaf drivers are retired and they value ease of access.

The most prominent feature of the Leaf is the lights which are designed to aid airflow around the mirrors.

The headlights of this car are indeed impressive. The bottom front, bottom sides, bottom rear, rear sides, and rear roof of the car are all very unclean to the airflow, however.

A few crude aeromods done by an ecomodder to a Nissan Leaf that do not affect the practicality or ergonomics of the car gave it a 20% range increase at highway speeds all by themselves:

http://www.mynissanleaf.com/viewtopic.php?t=19181

Also, the Leaf NISMO race car has a 0.25 Cd with a few minor modifications over the stock Leaf, and that's with the addition of a big, obnoxious, downforce-inducing rear wing. The Nissan Leaf AeroStyle kit that Nissan showed in a press release 4 years ago also looked interesting, but it was never placed onto the market.

The EV1 is indeed a somewhat small car, and reduced frontal area also reduces drag just as reduced drag coefficient does. The low drag form of the EV1 can certainly be scaled up in size to a taller vehicle, for say, a midsized sedan, at the expense of increased frontal area. The GM Ultralite of 1989, or even a 4-seater prototype of the EV1 from 1997, show this is possible. If the desired form is a hatchback, crossover, or SUV, take a look at the Mercedes Bionic(claimed 0.19 Cd), in order to get an idea of the type of drag reduction that Nissan could do to a tall hatchback such as the Leaf, were it re-designed to minimize drag while still retaining the ergonomic functions that appeal to the demographic of the retired.

A 0.19 Cd versus a 0.28 Cd would likely yield a range increase at 70 mph for the Leaf from ~90 miles to ~120 miles, without requiring an increased cost in batteries or to the car itself. Range, being a common anxiety among those considering the purchase of an EV, expands the potential market for the car as it increases, provided that cost remains a constant.

Someone is actually putting a Leaf battery/drive system into a 1st generation Saab Sonnet. I'm willing to bet it will go almost twice as far as the Leaf it came from on the same battery pack as the original Leaf, mainly due to reduced CdA and reduced weight, and will probably do 0-60 mph in under 6 seconds once finished thanks to the motor having 1,000 lbs less to pull around. Less is sooo much more...

Tesla's Roadster is a heavy brick by comparison to that Sonnet, even with the body kit upgrade offered for that Roadster. Automobiles have regressed over the decades, when it comes to the efficiency of their form... The 14.9 sq ft frontal area is one of the characteristics that prompted me to choose an old Triumph GT6 as a donor chassis for my conversion; this frontal area is more than 20% less than that of the GM EV1, and will reap huge benefits with regard to Wh/mile consumption and top speed. If I can get my drag coefficient down to 0.25(which seems doable considering that the ADU1B LeMans Spitefire had a 0.32 Cd without even having underbody paneling while maintaining a huge open grille to cool its lossy combustion engine, reaching 137 mph on the Mulsanne straight with only 111 horsepower), my overall CdA will be about as good as that of the GM EV1, except that my EV will be almost 1,000 lbs lighter, than the GM EV1... Less is sooo much more...
 
Food for thought :)

With the Leaf falling short of the 100mile range mark in it's current form, it does seem a little strange they didn't go for the low-hanging fruit and make it more aerodynamic.
 
I have no facts, but I'm pretty sure that there are big compromises made to car shapes in order to make them more practical for economic manufacturing processes.
You could make a care any shape you want, but if you want to produce it in high volumes, fast, and economically, you have to use materials, shapes and processes that are not ideal for optimum aero results.
It may be easy for owners to modify production shapes to make improvements, but that doesn't mean it would be economical , or practical for manufacturers to do the same .
 
I read through all of that thread on that forum and I have several reservations about the improvements. The first of which was that it wasn't easily replicable by others. A 20 per cent improvement is an awful lot for just small deviations (adding solid disc wheel covers, blocking up the air intake and rearranging the front mudguards to divert airflow away from the wheels) and it should show up but several noted no improvement - though I don't believe they used the solid hub covers.

Only one of those changes doesn't have a potential drawback - the mudguard mod. Blocking the airflow, even if it allowed some partial flow, isn't the smartest course of action when it is needed for cooling (air-cooled battery) and AC. And even in a car with regenerative braking, running solid discs can affect the brakes performance by hindering disc cooling. Through I will concede that solid hubs should net between five and six per cent improvements.
 
Hillhater said:
I have no facts, but I'm pretty sure that there are big compromises made to car shapes in order to make them more practical for economic manufacturing processes.
You could make a care any shape you want, but if you want to produce it in high volumes, fast, and economically, you have to use materials, shapes and processes that are not ideal for optimum aero results.
It may be easy for owners to modify production shapes to make improvements, but that doesn't mean it would be economical , or practical for manufacturers to do the same .
Complete and udder bull shit.
 
There may be some compromises required to turn the design model into physic product, but steel or aluminium can be pressed into all sorts of shapes, and the assembly line will find a way to screw it together. I think the main compromises affecting aero design would be (or perceived as): goofy styling, lack of interior space and slightly increased manufacturing cost. As has been demonstrated in this thread though, a aero design doesn't have to be any of those things in reality.

Based on the first few posts in that thread about the DIY Leaf aero mods I was completely unconvinced by the 20% improvement claim and the wisdom of blocking off the grill and over-inflating the tyres.
 
Most Leaf's will spend their life in urban traffic, commuting, shopping runs etc, and rarely benefit from improved aero.
They probably aimed for headroom, ease of entry, passenger space, etc, rather than optimum aero shape.
..oh , and no, you cannot just bend steel or Aluminium into any shape you want without some careful selection of material properties, and for tricky shapes, pre and post operation heat treatment....all of which take time and add cost to the product.
Why do you think so few "concept" cars ever end up looking the same when they make it to the showrooms. .?
 
It is possible that the driver could be unconsciously biasing his driving style to be more efficient, but there is still a lot more than just his mods that could have been done to the Leaf in search for an efficiency improvement, without any huge compromise in practicality. None of those mods made any major compromise that would impair the vehicle's normal use.

The rear of the Leaf had a lot of room for improvement too, but that funky rear-end styling just hinders it, and although a side-silhouette of the car is shaped very well with a good fineness ratio for the application, there is room for the roof to taper back longer without affecting the car's total length or wheelbase away from its application. It could still be a hatchback, and have slightly increased storage volume without decreasing headroom, were the rear shaped more ideal with regard to drag reduction from the factory. As the Leaf currently exists, putting a coroplast roof extension on it might yield interesting results. If basjoos' 90+ mpg Honda Civic DX is any indication, big 15%+ improvements is possible from that(he's published individual contributions from his modifications, with the rear roof extension and boat-tail yielding 30%+ improvement in fuel economy at 70 mph). But it would from then on look like a rolling science project...

Rear wheel skirts alone are probably worth a good 2-3% range improvement at 60 mph just by themselves, by cutting off the rear wheel turbulence. An ecomodder named Darin has had results of that sort with a gasoline powered Geo Metro, doing a more rigorous A-B-A testing and sharing measured results, versus what little was shown in that topic on the Leaf claiming 20% improvement for a few small mods.

Without rear skirts, the NISMO Leaf can still get a 0.25. Without that obnoxious rear wing, the NISMO Leaf would undoubtedly fare better on drag than a 0.25. Given this, scaling the shape differently and accommodating a taller body, somewhere under 0.25 should be doable for the Leaf models sold to the public, with it still being the same car, no practical compromises, not even the ones made by that poster claiming that 20% range improvement. I suspect Nissan's unreleased aerostyle kit would bring it to that 0.25 or potentially less. A 0.25 from a 0.29 would be a 9% improvement in drag, probably a 5-6% improvement in range, all by itself. More from there is possible, if you clean the rear portion of the car up with regard to its turblence-generating zones and get rid of the mudflaps. Rear wheel skirts, different rear shape(might add some skin friction, but make up for it in less generated turbulence zones), diffuser on the underside, ect.

Of course, a sedan lends itself more easily to an aerodynamic shape than a hatchback, but the Mercedes Bionic, Renault Vesta 2, and a bunch of other cars show that a tall-bodied(relative to length) hatchback shape with a 0.20 Cd or less is possible.

The extra work, materials, and processes that a lower drag shape would require, at worst, probably wouldn't exceed a few hundred dollars if cost of the vehicle is kept as a consideration. Bean counters in the industry do like to cut corners to squeeze that extra margin out, but it can end up costing the buyer more over the life of the vehicle in increased energy consumption and slightly more wear and tear due to increased power requirements for steady state cruising.

Volvo once admitted that its low-drag, 1500 lb, 86 mpg capable 1983 prototype, the LCP2000, would have had no price premium over conventional vehicles. It had a small turbodiesel of 1.3L and 50 horsepower. It was capable of seating 4 and designed with sufficient safety to allow all occupants to survive a head on collision at 45 mph with a much heavier vehicle. It only needed 50 horsepower to top out at 120 mph, and did 0-60 mph in 10 seconds, more than adequate performance for its time period and its performance competes with the cheapest stripped-down economy cars sold new today(base Nissan Versa, base Mitsubishi Mirage, ect). If it would have been built then in 1983, Volvo claims it would have also been the safest car Volvo had produced at the time.

Volvo sat on it instead. We don't have anything like it 30 years later, when the technology has improved by leaps and bounds versus then. Regulatory changes from the NHTSA could prevent such a car from selling today, but back in 1983, it was certainly more than doable.

This same story is repeated through the rest of the major automakers with similar vehicles in the last 35 years, ad nauseum. Many of their executives even admitted that these 80+ mpg cars such as the Renault vesta 2, Peugeot VERA+, Volvo LCP2000, Chevrolet Citation IV, Ford Probe IV, and such, were all "crisis cars", to only be built/sold in a severe global fuel shortage, but otherwise never to be pursued, regardless of consumer demand.

Aerodynamics, or the potential improvements they could bring, just weren't a major factor on Nissan's agenda for the Leaf, from the start. It is mediocre relative to other new cars sold on this criterion. Car designs like the Honda Insight, Infiniti G35 with aero package, Tesla Model S, and Toyota Prius all paid a lot more attention to this factor, to their benefit. The Leaf still fares better on Cd than a Honda Fit though, to its credit, but it is at the industry average.

In an EV, with limited battery capacity, "average" aerodynamic efficiency is very wasteful, if not counterproductive to the vehicle's potential market. Range is commonly seen as a sort of leash that is half of the vehicle's total range. With the Teslas, it isn't much of an issue because their range approaches that of gasoline powered autos, and long range trips almost exclusively involve highway-miles, where drag is a more significant factor with regard to range than city-miles. Even at low speeds of 30-35 mph, commonly seen in city environments, aerodynamic drag is already accounting for most of a vehicle's energy consumption during a steady cruise.
 
The Toecutter said:
.......... Even at low speeds of 30-35 mph, commonly seen in city environments, aerodynamic drag is already accounting for most of a vehicle's energy consumption during a steady cruise.
How much of a typical "city cycle" is a steady cruise at 30-35 mph ?.. And how much is stop/start, accelerating up to 30 , shuffling in line behind other traffic at < 20 mph, or braking to stop ?
Even on a city freeway you are rarely in "clean air" without another vehicle in front of you.
I suspect the real world Benifits of better aero are much less that theoretical for a city car.
 
I have read a rumor that Tesla is aiming to have a Cd for their Model 3 of under 0.20. If true, that is some excellent news and will allow for a less expensive battery to get more range. I'm also hoping it's light. Under 2,500 lbs for a stripped-down model would be excellent, and doable. An AWD, < 2,500 lb, CdA < 4 sq ft EV with a 300 horsepower drive system and AWD would out-perform cars 3 times its expected $35,000 price tag, and give double or triple the range per dollar spent over a fire sale marked-down Nissan Leaf.

http://www.greencarreports.com/news/1101046_tesla-model-3-to-aim-for-0-20-drag-coefficient-report

Hillhater said:
How much of a typical "city cycle" is a steady cruise at 30-35 mph ?.. And how much is stop/start, accelerating up to 30 , shuffling in line behind other traffic at < 20 mph, or braking to stop ?

Looking at chart showing the EPA Urban Driving Dynanometer Schedule, a simulation of 7.45 miles for urban driving in the U.S. that all new cars sold are tested against to determine their efficiency, it looks like roughly half of the driving done when the tested car is not stopped is at speeds over 25 mph. The average speed was low, just 19.59 mph, but since much of that chart has the car either stopped, or doing mostly 25+ mph while it is moving, assuming a 20 mph steady cruise would dramatically under-estimate the impact of air drag on range.

Weight will be the most significant factor in these conditions, but drag is still a significant factor, simply due to the speeds being traveled to.

Given the variety of situations, conditions, and individual drivers cars are subjected to, the reality is that the EPA cycle isn't necessarily accurate for A to B driving in the city 100% of the time, although it does provide a sort of baseline.

It is fair to say, using the EPA tests as a baseline, most drivers are probably going to be moving at at least 20 mph, or 9 meters per second, for the vast majority of the time that their vehicle is in motion and not stopped. I am going to estimate power required to maintain 9 m/s for two 2015 Leafs, one labeled as "Stock Leaf" with a 0.28 Cd, one labeled as "Aero Leaf" with a 0.19 Cd.

Here are the parameters:

Stock Leaf
Mass(M): 1470 kg
Drag Coefficient(Cd): 0.28
Frontal Area(A): 2.30 m^2
Rolling Resistance Coefficient(Crr): 0.008
Motor Efficiency(ME): 0.9
Controller Efficiency(CE): 0.98
Drivetrain/transmission Efficiency(TE): 0.95
Accessory Loads(AL): 1000 W

Aero Leaf
M: 1470 kg
Cd: 0.19
A: 2.3 m^2
Crr: 0.008
ME: 0.9
CE: 0.98
TE: 0.95
AL: 1000 W

At 9 m/s vehicle speed(V), assuming 9.8 N/kg for the force of gravity(G), we can use the following equations to determine the rolling resistance(RR), air drag(D), power at the wheels(PW), power required from the battery pack(P), to maintain 9 m/s for the two Leafs.

RR = Crr * M * G
D = 0.5 * 1.25 * Cd * A * V^2

PW = (RR + D) * V

P = AL + (PW / (ME * CE * TE))

You get the following power requirements at close to 20 mph:

Stock Leaf: 2588 W
Aero Leaf: 2430 W

Once you reach 20 mph, if you maintain it, the hypothetical Aero Leaf will from then on consume 6.1% less energy than the Stock Leaf. This is a 6.1% increase in range, at the average speed of the EPA city cycle.

Keep in mind, during the EPA test, usually the car accelerated past 20 mph, and air drag power consumption varies as a cubic function of speed, so the faster you go, the more losses your car induces pushing air out of the way, and for each stop, even with regen, most built-up kinetic energy from when the car was in motion is lost as heat, with acceleration requiring the bulk of the energy consumption.

I think it is safe to say that a very low drag car will still yield somewhere between 5-10% city mileage increase versus baseline for city driving. I've seen studies that have concluded similar 10+ years ago. Mass is a much greater factor during city driving, and the most important one, when it comes to energy consumption for this sort of driving condition. Given the variety of driving styles and conditions and the loading requirements presented by urban driving, a 5-10% difference can be certainly be reduced to "noise" when trying to predict day to day energy efficiency of your drive, but the difference still adds up, in the long run.

However, in the city, range isn't much of an issue. It would take 4-5 hours to use that Leaf's range up, driving around at city speeds, versus 1.5 to 2 hours to deplete the Leaf's 24 kWh battery, driving the speed limit on the highway. It's on the highway where this 80-100 mile range really becomes a limitation for the Leaf, and had the Leaf been more aerodynamically efficient, its utility would be greatly expanded as a result of increased highway range. City range, even a modest 5-10% gain, wouldn't matter a whole lot, but a 30-40% gain in highway range, allows the car to go a lot more places without running out of juice.
 
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