Super Efficient Cars [very large pictures]

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Post by NeilBlanchard » Fri Feb 06, 2009 5:02 am

Hi Aris,

There are a few steel components on the Aptera 2e: the front subframe (inside the nose) and front suspension struts, some drivetrain components, the wheels, bolts, etc. You're right though -- most of the chassis is composite materials that will not corrode.

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Post by spookmineer » Fri Feb 06, 2009 7:02 pm

Looking at all these pictures, and the concept behind it, I think it looks simply awesome. A bit like some of the cars in Back to the Future, but better. More desirable than a normal supercar, and feeling better about it as well.
It'll be a few years (?) before they are available in Europe, and a few more years after that until it will be affordable for me, but Jeremy Clarkson might even say (and he dislikes diesels, let alone electric cars) "it looks like a classic already".

This one might have more market penetration than Tesla, which approaches the market from "high end" to "low end", while Aptera try to make it affordable for most people straight away.

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Post by alecmg » Tue Feb 10, 2009 4:38 am

http://fastskinz.com/drag-terminology-defined.html

Basically a film on the car that reduces turbulence and drag and promotes laminar flow. The fuel eceonomy percentages they claim seem a bit unreal (albeit for a coffin-shaped Scion)

But I can see future cars sporting dotted look.
Poor mans carbon fiber :)
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Post by Mescalero » Tue Feb 10, 2009 7:53 am

What they write about laminar and turbulent boundary layers is correct, but they are exaggerating the seperation of the flow with a laminar boundary layer.
The flow will seperate above the windshield but it will reattach a little later on the roof, so the wake won't be as big as they show.

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Post by NeilBlanchard » Tue Feb 10, 2009 9:41 am

Hi,

That "golf ball skin" stuff cannot fix the aerodynamics; it can only have a minor affect. For the amount they charge to apply it (a LOT of $$$) it should turn it into a Prius, or better. But, I fear that it would barely make a noticeable difference, if even that...

Shape is the most important factor for good aerodynamics, and after that, details like, cooling/air intake grills, tight gaps, and surface bumps. Both of these completely swamp any possible benefits of this type of surface treatment.

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Road & Track test drive the Aptera 2e

Post by NeilBlanchard » Thu Feb 12, 2009 6:21 pm

Hiya,

Road & Track has road tested the Aptera 2e, and there are lots of pictures and several videos, complete with squealing tires:

http://www.roadandtrack.com/article.asp ... le_id=7651

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Post by L2GX » Fri Feb 13, 2009 12:36 am

NeilBlanchard wrote:Hi,

That "golf ball skin" stuff cannot fix the aerodynamics; it can only have a minor affect. For the amount they charge to apply it (a LOT of $$$) it should turn it into a Prius, or better. But, I fear that it would barely make a noticeable difference, if even that...

Shape is the most important factor for good aerodynamics, and after that, details like, cooling/air intake grills, tight gaps, and surface bumps. Both of these completely swamp any possible benefits of this type of surface treatment.

Olympic swimmers will tell you any benefit is a benefit, and go for the shark suit.
It's not an either or thing, anything you deduct from the drag is, well, deducted.

You're right though in that car manufacturers need to design cleaner cars. Some of the stuff that would make a difference is deemed ugly by the public, which is a consequence of marketing. Other issues are tolerances versus cost, outdated production methods, the intertwining of the car and steel industries...

Car manufacturers are sailing huge ships that don't turn around on a dime. It's easier to lobby than innovate, as has been and is demonstrated.

Car manufacturers could have (and have) come up with a lot of this technology years ago, but it's only now becoming cost efficient, if marketed at early adopters. Sadly the current innovators who are sticking out their neck are doing good work, but they're not going to provide the millions of cars the world buys every year. So they're going to be left behind by history and people will keep buying yesterdays techology on the car companies schedule.

And I will keep opening my front door every morning to get a good whiff of exhaust.

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Post by NeilBlanchard » Fri Feb 13, 2009 5:06 am

Hi,

My point is that they charge something like $4K for this "golf ball" treatment, and for a tiny fraction of that cost, you can yield far better improvements with say, and upper grill block that smooths and rounds the nose of the car; or smooth wheel covers, or rear wheel skirts, or a full underbody pan, or a Kamm back...

I've done a number of very effective improvements to my car (which admittedly is much better to begin with), but the same sorts of improvements can -- and have been done with the xB.

I've done them as quick and dirty as possible, and the costs have been about $40 total. The benefits are huge: my mileage has improved by at least 35%, and I'm averaging 42% above the EPA Combined rating for my xA -- and that is during the winter!

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Post by jaganath » Fri Feb 13, 2009 5:42 am

dimples are not used on cars due to the following reason: on golf balls, the majority of the drag is made up of pressure (or form) frag, which is caused by the large (relative to the size of the object) wake that forms behind the ball as it is travelling through the air. Dimples reduce form drag very effectively, hence its use on golf balls.

The drag force on cars, being much larger objects, is dominated by skin friction drag, and form drag contributes relatively little to the overall drag, therefore dimples would not make much difference. However, there are surface treatments that can make a difference, as you can see on the EVO 10 below:

http://hpautoworks.com/images/Evo-3.jpg

however, this is more to do with keeping flow over the rear wing stable than reducing drag.

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Post by Mescalero » Fri Feb 13, 2009 8:26 am

The major source of a blunt object like a car is still form drag.
It depends not on the size of the object but on its proportions. Cars, in contrast to airplanes, are still rather short compared to their width and height.
Up to 80% of the total drag of a car is actually form drag.
It's not just the wake though, there are also complicated vortex structures behind the car, which add to the drag.

I don't think the golf ball skin will do a lot of good, and since it's dead ugly nobody would want their car to look like that anyway.

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Re: Road & Track test drive the Aptera 2e

Post by Ralf Hutter » Fri Feb 13, 2009 8:32 am

NeilBlanchard wrote:
Road & Track has road tested the Aptera 2e, ...complete with squealing tires:
What'd they do, slide it sideways down a steep hill? :)

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Post by NeilBlanchard » Fri Feb 13, 2009 9:57 am

Watch the videos, and find out! :P

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Post by alecmg » Mon Feb 23, 2009 9:59 pm

China's largest independent carmaker Chery Automobile releasing their first plug-in electric car. Known as the S18, this electric car is able to travel up to 150 kilometres (93 miles) per charge with a top speed of 120 kilometres (72 miles) per hour. It takes around six hours to juice up the car from your regular 220-volt home outlet, where 80% of the battery can be charged within half an hour.
Chery also promises that the car would be affordable when launched.
http://www.ubergizmo.com/15/archives/20 ... c_car.html
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Post by NeilBlanchard » Sat Mar 21, 2009 4:49 am

Last edited by NeilBlanchard on Sat Mar 21, 2009 4:29 pm, edited 1 time in total.

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Post by Mescalero » Sat Mar 21, 2009 7:16 am

Good article. When they complain about the road noises it's probably just because they aren't masked by any engine sounds that makes them sound loud.

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Post by alecmg » Tue Mar 24, 2009 2:27 am

http://www.dailytech.com/Worlds+Cheapes ... e14645.htm
600kg unloaded, 624cc 33 hp engine and no gizmos attached

If only it wasn't so damn ugly...

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TESLA finally gets it: Electric Sedan Less Than $50K

Post by silchris » Tue Mar 24, 2009 5:18 am

Source : National Public Radio (see npr DOT org, I'm a longtime reader of SCPR but not enough posts to put up links)

Hey, Tesla... It's really nice to see you finally grasp that ECs are NOT just for the rich and famous. There is a HUGE market waiting for any company that makes a car that... is safe, SIMPLE and reliable (less parts and repairs costs at $100/hour, sure can't count on GM for that) and costs less than a buck to recharge on AC at home for the next 100 miles.

After all, for all the childish hoopla generated by Detroit and the Automotive Media (7 seconds from 0 to 60, 250 HP fotr a minivan, 20+ separate computers on new car models, etc.) the way we Americans REALLY drive is from point A to point B slowly hopping across town and/or going to work at an average of 50-60 miles per hour due to urban sprawl and congestion.

There will always be "dream cars" and that's that's fine, but we want CARS FOR THE REST OF US.

With cos like Tesla and some of the others referenced in this thread, maybe there's hope <g>.

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Post by NeilBlanchard » Wed Mar 25, 2009 7:54 am

Wow!

The new Prius is able to put up some very impressive numbers! One of the worst was 64.5mpg. About half of the journalists did better than 70mpg; a median was ~75mpg, and the best was 94.5mpg!

http://www.autobloggreen.com/2009/03/25 ... #continued

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Post by NeilBlanchard » Fri Mar 27, 2009 5:55 pm

Hi,

Another video about the Aptera:

http://www.youtube.com/watch?v=LJCDH1xX ... r_embedded

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World's Fastest Electric Car!

Post by NeilBlanchard » Sun May 03, 2009 2:14 am


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Post by stromgald » Mon May 04, 2009 12:41 pm

That's pretty good considering he made it all himself. It isn't the fastest though. I think the Tesla Roadster has slightly better numbers.

I'm glad they're making fuel efficient cars that actually look/perform normally. This isn't targeted at Priuses or the styling of electric cars, but more at the "smart" cars like the Yaris, Fit, and smart fortwo that are very fuel efficient but are so small and lightweight that they do nothing in a crash. They seem to be the craze these days (or it might be because I'm in California). IMO, the current gas engine technology has gone about as far as they can go and cutting corners on safety isn't a solution I'd buy. Despite the cost, improved engine technology is the only viable solution IMO.

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Post by NeilBlanchard » Mon May 04, 2009 6:42 pm

Hello,

Wikipedia has the Roadster's 1/4 mile time slower than the White Zombie:
The Roadster's 0–60 mph (0–97 km/h) acceleration time is 3.9 seconds for the Standard Model and 3.7 seconds for the 2009 Sport Model. Some prototypes and early production 2008 Roadsters were limited to 5.7 seconds.[3] The top speed is electronically limited to 125 mph (201 km/h). The Roadster covers the quarter-mile drag strip in 12.757 seconds at 104.74 mph (168.56 km/h).[49]
http://en.wikipedia.org/wiki/Tesla_Roadster

I think the new Fit and the Smart ForTwo, and the forthcoming iQ are all very crash worthy cars. Big & heavy =| safe.

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Post by stromgald » Tue May 05, 2009 8:28 am

NeilBlanchard wrote:Hello,

Wikipedia has the Roadster's 1/4 mile time slower than the White Zombie:

http://en.wikipedia.org/wiki/Tesla_Roadster

I think the new Fit and the Smart ForTwo, and the forthcoming iQ are all very crash worthy cars. Big & heavy =| safe.
Ah, I looked up the article I was looking at yesterday, and I was looking at the wrong specs. It was for another electric car, probably not street legal. :oops:

Big & heavy != safe, but well designed big & heavy cars are safer than well designed small & light cars. Most government safety ratings are skewed since cars are measured only against crashes against cars of similar size/weight. On the road, on average, larger cars are safer simply because they're bigger, heavier and carry more momentum into the crash. This is basically the result found in the IIHS test released last month of Yaris, Fit, and fortwo vs mid-size cars.

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Post by NeilBlanchard » Fri May 29, 2009 7:56 am

Hi,

Here's an Aptera 2h competitor that has come out of the woodwork:

Image
(click on image for link)

It's a serial hybrid with very reasonable claims being made. It's great to hear about new design; and they seem to have gotten several things right! The aerodynamics start out right, but seem a little schizophrenic with the good shape and full underpan -- but then having the open wheels; especially the rears with the separate fenders. Overall, cool stuff!

I love the fact of it being a serial hybrid -- this seems to be the obvious and best choice for the immediate future when longer range is required. The Aptera 2h is the only other one I know of that is an (intended) production car -- it is purported to get a minimum of 130mpg! There was/is the converted Mini with four 160HP hub motors, and a little 2 cylinder 250cc engine to charge the batteries -- 640HP and ~85mpg possible! What not to like?

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Post by NeilBlanchard » Wed Jun 17, 2009 2:37 am

Hi,

Here's a new one; the Riversimple opensource hydrogen fuel cell car:

Lease this car for $315/month!

Image

Image

Not too many details are available yet: it has a 1kg tank of hydrogen and a whopping 6kW (8HP) fuel cell that give it a range of 240 miles, and a top speed of 50mph. They are looking to produce 10 next year, and ~50 the year after that, with leases available in 2012, for £200 ($315) per month, including the hydrogen fuel. Key to their design is efficient regenerative braking (50% returned energy) using some ultracapacitors.

It looks like they are using hub motors in each wheel, and carbon fiber for the chassis. It does not appear to be on their web page (yet), but they plan to release their plans so that anybody can build one. I really like this idea of sharing the design information. The aerodynamics seem to be worked out pretty well -- the range of the car with just 1kg of hydrogen is proof of this! The one (possible) snag is whether or not the side windows are operable -- I guess toll roads can be handled with a wireless unit, though. There is an intake grill, which may be used for ventilating the car.

I have my concerns with hydrogen -- you can either get it from processing natural gas (which is obviously not very "green") -- or you need to use renewable energy (electricity from solar/wind/tidal/wave/biomass, etc.) to make the hydrogen. There is no infrastructure for hydrogen, and this is a nontrivial hurdle. But with this Riversimple car, they provide the hydrogen as part of the lease. So this design concept works if you are located close to where they will have service.

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Nissan Leaf

Post by NeilBlanchard » Sun Aug 02, 2009 2:02 am

Hi,

http://www.autobloggreen.com/2009/08/01 ... and-u-s-b/

Image

100 mile range. Cost of mid-lin Altima. Volume retail sales in USA and many places by 2012.
Powered by a unique array of thin, laminated lithium ion cells capable of delivering over 90 kW of power, the Leaf's front-mounted electric motor delivers 80 kW (107 horsepower) and a healthy 280 Nm of torque (208 pound-feet)
Perhaps more important than the Leaf's top speed are its battery's charging characteristics. In this regard, the car's under-floor mounted assembly of 48 lithium ion modules (each laptop-sized module is comprised of four magazine-sized cells) offers a number of charging strategies. To yield a full charge, a 200-volt, single-phase AC charger takes less than eight hours, and topping off the battery from a 100 volt single-phase standard home wall outlet will take somewhere around twice that time, so prospective Leafmakers would do well to get 220 volt hookup like their clothes dryer uses out in their garage.
Image
More impressive is the battery pack's 50 kW DC fast-charge capability, which is capable of accepting an 80% charge in less than 30 minutes, or an extra 50 km (31 miles) worth of range in about 10 minutes. For that, though, you'll need access to a special dedicated (and at around $45,000 – expensive) three-phase charger, which various cities around the globe have begun installing as part of their own greening strategies. The executives we spoke with says they are working with local governments in the States and around the world to help build supporting infrastructure, but they admit the automaker has no plans to financially support the networks themselves, and fast chargers like the one we experienced in Yokohama are clearly cost-prohibitive for private ownership.
Pretty sweet!

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Post by Mescalero » Sun Aug 02, 2009 10:40 am

160km looks better than those 40km or what the Chevy Volt has, but still, to own a car which won't even allow you to visit the next city? I don't know.

Even though in Germany every house has a 3-phase connection for electricoal stoves and such devices (not sure if it's 400V or 230V) the infrastructure is a problem. What if you don't have your own garage (I know hard to imagine for Americans)? You couldn't recharge your car during the night.

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Post by NeilBlanchard » Sun Aug 02, 2009 12:05 pm

Hi,

It is standard to have 120v in every house, and in almost every house, you can also have a 240v outlet. This is pretty easy to do. The 3-phase stuff is obviously a bit more involved, though I'm not sure why it is so expensive?

70% of Americans drive less than 100 miles a day, and something like 50% drive less than 60 miles a day. Longer trips will require: planning, and/or renting another vehicle, and/or taking other modes of transportation. There will be serial hybrids that "extend" the range; like the Volt and the Aptera 2h.

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Post by Mescalero » Mon Aug 03, 2009 1:50 pm

Longer trips will require: planning, and/or renting another vehicle, and/or taking other modes of transportation.
Exactly why no one is going to buy such a car. I'll spare you all that stuff about freedom etc. etc. People like cars becuse it spares them the inconvenience of having to plan ahead and having to rely on other people. People like to have a vehicle that is always ready to go and can take the at any time to any place (with enough time).

Is this a great car for everyday use? Absolutely!

is it a replacement for a car like the one you own today? Absolutely not. (IMO)

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Post by K.Murx » Mon Aug 03, 2009 1:59 pm

stromgald wrote: Big & heavy != safe, but well designed big & heavy cars are safer than well designed small & light cars. Most government safety ratings are skewed since cars are measured only against crashes against cars of similar size/weight. On the road, on average, larger cars are safer simply because they're bigger, heavier and carry more momentum into the crash. (...)
Sorry, I know it is a bit late to start an argument on that, but I just could not let this stand unopposed.
Well designed big & heavy cars are safer than a small car only in the event of a crash. This does not mean they are "safer" than small & light cars. The handling of any "heavy" car is by its very nature abysmal, and even worse if it is also big (which I take to mean "tall"). Try the Moose test with a SUV and a decent Sedan/small car, and see for yourself.
All the metal in the world will not help you after you tried to swerve around the stereotypical child & his ball, avoided the oncoming "real" truck, and rolled and hit the bridge.
Btw, 4WD only excacerbates the problem, as many, many drivers severely overestimate their vehicles ability because it is accelarating just fine - braking and steering is a whole other matter, but well...

Sorry for the rant, pet peeve ;)

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