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Efficiency? Think Racing Cars, Not Hybrids
Gordonjcp writes "A renowned racing car designer has said that car manufacturers should be looking at making cars lighter to improve efficiency, rather than adding complex drive trains. In this article on the BBC News website, Professor Gordon Murray explains that a weight saving of 10% in a normal car would make more difference than switching to a hybrid engine and motor combination. Could this be the next nail in the SUV's coffin?"
Cars need to be lighter and more aerodynamic. The drag on a standard automobile is just ridiculous. Rear ends today are typically vertically flat! Who are these designers that aren't familiar with the teardrop shape?
Developers: We can use your help.
Lighter SUVs flip over easier. How could you prefer any SUV when it's far less safe? Minivans and station wagons at least have better crumple zones to protect you in a crash. Even those half-SUV/half-car things use car frames with proper crumple zones and have a lower center of gravity.
Developers: We can use your help.
Safety devices in cars are the major reason that fuel efficiency hasn't significantly improved since the 70s. Since the 70s and 80s up to 500 kg have been added to cars in the form of safety devices. For example, a 1979 Honda Civic had a curb weight of 680 kg. A 2008 Honda Civic has a curb weight of 1180 kg. A 1980 Toyota Camry had a curb weight of 1000 kg. A 2008 Toyota Camry has a curb weight of about 1500 kg. This 500 kg rule applies across a broad range of vehicles.
Ford relies heavily on sales of its SUVs and full-size pickup trucks in the U.S. market, but the U.S. demand for the large vehicles has been shrinking for several years and the declines accelerated in the last couple of months as gas prices rose above $3.50 per gallon.
init 11 - for when you need that edge.
What is really surprising is that despite the common consensus, SUV's are NOT safer than small cars.
Even a tiny car vs. an SUV you are just as likely to walk away in the small car as the SUV.
Now, tiny car vs Mack truck, Mack truck wins everytime...Mack truck vs SUV and guess what, Mack truck wins every time.
It is true that you are more likely to TOTAL a small car but if it is safety you are after than ANYTHING that passes crash testing is more than safe for everyone but professional racers. Wear your seat belt, check your tires and breaks and DON'T cut people off with 36 inches to spare at 80+ MPH!
The SUV safety myth was created by marketing pure and simple.
The original Lotus Elise got almost 30 mpg with 1.8l, 120 hp, and it was a high-performance car.
Put a little 1 liter, 60 horsepower engine in there and it'll probably get 50 mpg, but have regular car performance.
The secret? Weighing only about 1,650 lbs.
Because basically a long time ago, someone discovered that you can cut off the tail of that teardrop, and the air flow will still be largely the same. Only this time without the added mass and drag of that teardrop tail.
And especially if you read the RTFA, weight is a big problem. Increasing the car's weight with a useless tail would negate any aerodynamic benefits anyway. If you save, say, 0.5 litre per 100 km in aerodynamic drag with a tail, but pay 1 litre per 100 km to move that extra weight, it's not worth it.
A polar bear is a cartesian bear after a coordinate transform.
I don't know about most American cities, but where I live gas would have to be $10 a gallon for years before it would be concievable to move close enough to work to walk or ride a bicycle. American cities are failing to provide the infrastructure to do anything like that and the few people who might be interested are far outweighed by the majority. Further, companies are more than willing to send their employees to other locations ad hoc with little regard to their personal needs. I was once next to a man on a plane who took an 8 hour flight to work every monday and flew back every friday because his was a specialized field and the company wanted him to work somewhere far from home.
A truncated teardrop with a flat back (like the Prius or the Insight) is actually more aerodynamic than the teardrop. It's called a Kammback, and it's named for the gentleman who noticed that if you chop off the back of the teardrop, the air keeps flowing the same way, except without the drag of sliding along the surface of the parts of the teardrop you just chopped off.
Several years ago I had an the opportunity to talk to one of the design engineers for Saturn at an auto-show. At the time they were researching ways to make all the body panels out of plastic, the hood and trunk lids needed to be metal, due mostly to the heat they absorb. The eventual goal was to mold the car's color into all the plastic parts, to eliminate the need to paint any of the exterior parts of the car. One problem they had with this process at the time is that bumper plastic is different from the fender plastic, and tinting the panels to match exactly was very difficult. One big benefit to the consumer was the ability to just sand minor scratchs and scrapes off the car. No need to repaint. I am surprised that we have not seen more of this type of innovation. Making more parts out of plastic would lighten the load of the car.
Have you ever had a tire blow out? I have, I was doing 65, the tire went bang (thanks to truck debris spillage slicing my wall), my car just continued normally, no swerve, no panic, just a slight leaning to the front right. When I pulled over I was surprised to see my tire was utterly flat. I had no idea what the noise was until I went around the car looking for damage.
Yoy say an SUV will swerve for the same thing. Yet more evidence SUVs are not safe. Have fun digging that glass out the kids when you roll over.
Get this into your head, fast cars are safe. They are designed to stop fast, turn fast and hold the road. SUVs do none of this. Each SUV has warnings they may roll over above the driver's seat. Doesn't that tell you something?
A good example of this is an F1 car - they are designed with crashes in mind. They have strong central component to protect the driver with everything else breakable to take energy away from the tub that the driver sits in. Take Robert Kubica's accident in the 2007 Canadian Grand Prix, for example, After contact with Jarno Trulli, his car hit a bump, lifting it and rendering him unable to steer. His car hit a safety wall at approximately 28G decelaration and then tumbled down the track, finally coming to rest against another safety wall on its side. Most of car was strewn along the track, but the tub protected the driver. He not only lived to race again, but suffered little injury.
Noted, these are very, very expensive cars, are single seaters, don't have doors (making the carbon-fiber tub that the driver sits in much easier) and not really designed to run on the street, but the concept of sheddable body around a strong central area still could apply
Of course this makes the car more costly to fix which will annoy insurers and leaves a nasty very sharp mess on the street if you use the baked carbon fiber that they use on F1 cars, but if you want to make cars lighter and still protect the driver and passengers, it's worth looking at...
Amory Lovins, in his excellent TED Talk on Winning the Oil Endgame, makes an argument that weight savings need not lead to descreased safety. An example that he cites is a hand-built McLaren that has a couple of woven carbon-composite cones in the front that absorb the energy of a crash. Well worth a listen.
The "cue the foo posts in 3, 2, 1..." posts will commence with no subsequent foo posts in 3, 2, 1...
An Expedition is safer than a Civic, but not so much as the tenor of this whole thread would imply.
My brother, while driving a compact sedan with 2 passengers, got hit from the side by a truck driven by an inebriated driver. My brother and the passengers were fine. Compact cars today are better than a lot of vehicles from 25 years ago.
SUV's are still going to win the mass battle in collisions, but part of the design of an SUV is that it should crumple, rather than chewing through what it crashes into. This helps the occupants of both vehicles.
Nerd rage is the funniest rage.
I can't help but correct you here--power is not reclaimed; energy is. Power is the rate of energy's flow.
Sadly, the (1/2)*mass*(velocity^2) isn't worth very much, and we don't even come close to recovering all of it. For a 2000 pound car going 55 mph, that's about 90 Whr or roughly 1/400 of a gallon of gasoline. Then multiple that by the efficiency to get what you're really recovering (not much).
My car has something far more efficient than regenerative braking; It has me behind the wheel.
:-)
I have this thing called look-ahead, where I notice that there's a traffic hazard or near-certain stop 500 yards ahead so I take my foot *OFF* the accelerator. The car stays in 5th and coasts up to the obstruction/set of lights/roundabout with me changing down while coasting, if necessary, and watching the traffic ahead so I fit in without having to stop. Brakes are for the relatively rare occasions when this doesn't work.
Usually, the impatient guy behind me who undertook me in order to reach the traffic lights first ends up eating my dust, because *he* had to brake to a halt, while I'm still rolling.
I get 50mpg around town, and 60-70 on long trips with 4 people in the car and a full boot. That nice suspension thing we Europeans do so well means I don't have to slow down so much at corners to avoid understeering into a tree, so I don't waste energy to braking, and the kids love the rollercoaster ride through the Chilterns
It's a Diesel. Better performance than a Prius *and* more fuel efficient. You just need proper standards for the fuel so you don't choke.
Worth mentioning.... the aforementioned McLaren was designed by Gordon Murray... the author of the article. He's also been a very successful designer in Formula One.
this is something most of the posts I see have missed. Not only is he an F1 designer - he's a *good* one. This guy understands perfectly well all the crash dynamics that dozens of posts here are complaining about. Carbon fibres or even the engineered cellulose in an article below this one should be looked at.
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You hit a light pole in a miata, and you'll go through it. They're designed to shear on impact to protect drivers. You hit a *power* pole in an excursion, and you're dead.
In order for the miata to have the same energy-of-impact as the excursion, it would only need to be going 40% faster. So you gotta ask yourself, In a place where the ford is going through a neighborhood at 30 mph, how unlikely is it that the miata driver would be zipping along at 42 mph?
Can you be Even More Awesome?!
I almost bought a Camry in 1987, but decided to get a Ford Taurus instead. It felt like a much more substantial car. I drove it for 10 years and 150,000 miles.
Today's Camry is smoother, quieter, faster, and safer than the 1987 version.
Bigger and heavier, but not by 500 kg!
1987: 1,240 to 1,295 kg, 4.52 meters long, 1,69 meters wide, 1.37 meters high. 96 kW or 118 kW engines (130 hp I-4 or 160 hp V-6)
2007: 1,489 kg, 4.80 meters long, 1.82 meters wide, 1.47 meters high. 118 or 200 kW engines (158 hp I-4 or 270 hp V-6)
How the hell did this get a +4 Interesting? If they're impossible to pass on some roads then slow down and do'nt pass them. Sorry buddy, but they've got just as much of a right to be there as you do*. I think the ~45 seconds you might lose on your commute won't kill you. You must have never ridden a bike, because it's impossible to be "blissfully unaware" of the cars zooming by you honking their horns and coming within inches of killing you.
*Laws vary from state to state, but most states have a law that says that bikes have the same rights/responsibilitys as cars.
What you want is the Tata Nano. $2500 http://www.autoblog.com/2008/01/10/what-2-500-buys-in-india-tata-nano-unveiled/
Gas prices increasing to the point where driving a light, efficient car is the only option is not going to happen you say? I beg to differ. Here in The Netherlands, it's already happening. There has been an extreme increase in gas pricing the past year. You now pay E 1.65 per liter, which is about $ 9.21 per gallon. Yes, you read that right. For a full tank in a small to medium sized car (40 liters), you easily spend over 60 euros. That's $ 100 for a tank of gasoline.
Over here, even in the rich suburbs people are selling their SUV's and buying small cars like Mini's and Fiat Panda's. The number of SUVs sold is dropping rapidly. It was recently in the news that last year, the amount of SUV's sold was only 1/5 of the year before that.
Pretty good is actually pretty bad.
No. Diesel is popular in Europe because it gets better mileage. Every company and their brother has a diesel vehicle in Europe, if you don't you're SOL in the market. Manual transmission too.
I have a 1998 Jetta VW that can haul 4-5 people. A weekend of luggage and still get 45 MPG. Even with diesel pushing $5/gallon it's still cheaper per mile than any gasser OF THE SAME SIZE.
"Heavier Diesel". You talk about it like it adds 2 tons to the vehicle. A diesel engine may add a few hundred pounds at most.
VW has a PRODUCTION car that they sold that got 78 miles per US gallon. There is nothing more frustrating than hearing about the 'amazing' 30 MPG that some small cars get while in Europe they're doing double that.
What??
I'm thinking you need to go back to physics class.
Let's assume that, as you say, the small car "moves with the force of the SUV". Let's assume that both vehicles are travelling at 100 km/h, and hit head on. The end result? Your small car is now travelling BACKWARDS at 25km/h, while the SUV is continuing on it's original path at 25km/h. That means that the occupants of the SUV have experienced a decelleration of 75km/h, while you, in the same period of time, have experienced a deceleration of 125km/h.
Who do you think comes out ahead in that scenario?
Granted, that's a very simplistic model, but it does clearly show the absurdity of your argument
SUV are much, much worse at avoiding collisions, and are more likely to be involved in accidents per driver miles.
..........FULL STOP.
The crash statistics alone indicate that feeling safer in an SUV is a false sense of security. Could have something to do with many soccer moms not being able to see over the dashboard. That and the tendency to roll over when driven like a sports car.
I beg to differ on the whole 'climate' issue.
From Weather.com
Average weather in Washington DC
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/USDC0001?from=search
Yearly spread - 61 degrees farenheit
Average weather in Chicago Illinois
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/USIL0225?from=search
Yearly spread - 66 degrees farenheit
Average weather in KC Kansas
http://www.weather.com/weather/wxclimatology/monthly/graph/USKS0298?from=36hr_bottomnav_undeclared
Yearly spread - 69 degrees farenheit
Average weather in Dallas Texas
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/USTX0327?from=search
Yearly spread - 60 degrees farenheit
Average weather in Paris, France
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/FRXX0076?from=36hr_bottomnav_business
Yearly spread - 41 degrees farenheit
Average weather in Berlin, Germany
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/GMXX0007?from=search
Yearly spread - 48 degrees farenheit
Average weather in Madrid, Spain
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/SPXX0050?from=search
Yearly spread - 58 degrees farenheit
(No average information available for London, UK)
ABIL
Mod parent up! Not only is the 12-year-old McLaren F1 still one of the quickest and fastest cars ever built, it does it without resorting to 4 turbos and 1,001 horsepower simply by being lighter.
Not only that, but Murray also worked to finalize the design of the (already nearly complete) Caparo T1, which is even quicker (0-60 in 2.5 seconds), and with less horsepower than the F1. How? It weighs about half a ton.
The difference between spam and poop is that you don't have to dig through septic tanks looking for real food. -- Me
You must have a TON of equipment, I don't know how much you need but I drive a subcompact (Honda fit) and I can fit 2 mountain bikes in the back as well all our gear and clothes for the weekend. A 7' christmas tree, a full size BBQ in a box (didn't even need to fold down the rear seat for that one!) if need be me and my wife could sleep in this car, with all our stuff.
Unless your hauling around large items (tables, large speakers, etc) I have a hard time seeing anyone being pushed for space in this car.
Offroad? How about a Subaru station wagon, those have a lot of room on the inside, and work well enough in the dirt. Fireroads don't count as offroad, unless your lifting a wheel, crawling over rocks, or digging through mud you probably don't need something with live axles or low 4wd, and a normal sized car would work just fine. heck you can still drive through small rocks with a Subaru on occasion
SUVs have their place, some people really do need them, you might but I don't know you. But MOST people don't NEED them, even when they think they do.
Actually look at the study. It actually correlates even more strongly with manufactures than it does with vehicle type. With GM and KIA being the death machines.
(newer study: http://www.iihs.org/sr/pdfs/sr4003.pdf)
Mini four door cars are poor. But they only have 3 cars in the study 2 poor Kia/Huyndais and 1 Toyota Echo. The echo does very well.
The most deadly vehicle in the study is the GM blazer. 4 times as many death as a the tiny toyota echo.
If you want to use this as any kind of basis it would have to be model vs specific model, not generalizations based on body type. You would somehow need to move driver disposition from it as well. Sports cars don't kill their drivers, it is some of the idiot that buys a sports car that gets themselves/others killed.
I remember a lecture from one of my profs who used to work with the NTSB. He mentioned crash fatality studies where moving from a car-car collision to a car-suv collision made little change on the probability of death to the SUV driver, but significantly increased the probability of death to the car driver. thus, according to that metric, the bigger vehicle only serves to increase the other person's chance of dying without making you any safer.
What I mean by large scale is not the size of the product, but the cost and number of them. Carbon fiber is used in a lot in aerospace, but that's because cost is a lot less of a factor than with automobiles. I've heard recently that the boom in aircraft carbon fiber use has caused a jump in the cost of the raw material itself, and this was before the recent increase in fuel prices.
Well, most cars will be officially totaled if the airbags go off. In a car with head curtain airbags, the replacement cost is too much to justify fixing the car, even if there's little other damage.
Current hybrids include storage batteries that weigh a lot. They can be replaced with a much lighter flywheel that also has a higher efficiency than batteries, at storing and releasing energy (and also works with regenerative braking). Do not confuse this with other decades-old ideas of using flywheels to fully replace the car engine; we cannot make them strong enough to hold energy for 300 miles of travel. But we can easily make them able to hold enough energy for a few bursts of rapid acceleration. The only reason a smallish car has a 100HP engine is to get rapid acceleration. Any hybrid can replace that with a much lighter 15-20HP engine, which produces plenty for cruising at a fixed speed, plus some extra to charge up the storage unit for the desired rapid acceleration. A hybrid that uses a flywheel might weigh about the same as the ordinary car, but it will get better gas mileage because of the smaller engine.
Cyclists should be riding on the sidewalks. The relative momentums of bike riders and pedestrians are much closer than bike riders and multi-ton vehicles. The traffic laws for bicycles seems to hearken back to the days when an automobile's average speed was 15mph.
No, they don't. In Europe, all those people have a small van.
Something like one of these: http://www.citroen.co.uk/new-vans -- probably from the first two rows.
Collisions are governed by momentum, not kinetic energy. Momentum is what will carry you into the house, kinetic energy is what will dissipate into damage.
Sadly, nearly everyone thinks that.
You're still blocking everyone else's line of sight.
In case anyone actually believes this: http://en.wikipedia.org/wiki/Waterpowered_car Sorry to spoil your fun.
-Xoltri
don't forget that those automatic transmissions weigh a great deal more (50-100 extra pounds) and typically offer far worse gearing for fuel economy... good luck finding a modern car with a stick-shift unless it's a sports car or you custom order it.
For the average drive (and even the average driver who thinks they aren't) an auto will provide as good - likely better - fuel economy as a manual.
The biggest problem with a lot of autos is that they *are* geared for economy, which results in relatively poor acceleration. So people who like to exercise their inadequacy by trying to win the stoplight drag need to bury their foot into the floor to do so, burning much more fuel than they need to.
If you can't see the value in jet powered ants you should turn in your nerd card. - Dunbal (464142)
On a real track or road, with full aerodynamic gear, an F1 car would smoke the Bugatti. For an idea of what an F1 can do, see this comparison of Formula 1 Car vs Ferrari 550 Maranello vs Fiat road car.
"When I first heard Daydream Nation it quite frankly scared the living shit out of me." -- Matthew Stearns
You do realize that all the "entry level" cars, such as the Hyundai Elantra, Toyota Corolla, Honda Civic, etc. all come with manual transmissions standard, right? On all these cars, getting an automatic transmission is an option that adds to the cost of the car.
We all know what to do, but we don't know how to get re-elected once we have done it
When was the last time you bought a car? I bought my '07 Hyundai Elantra last year, and I can tell you that there were at least as many manual on the lot as there were automatics. I shopped Toyota Corollas and Honda Civics too (not as extensively), and they too had plenty of manuals on the lots.
As for incentive packages, I don't think I've ever seen an incentive package for one of these cars that said "You have to get the automatic version", in the fine print.
We all know what to do, but we don't know how to get re-elected once we have done it
http://www.youtube.com/watch?v=k3ygYUYia9I
It's a crash between a Volvo 940 (big car: 4.80m, but bad Euroncap rating) and a Renault Modus (small european car: 3.90m and great Euroncap rating: 5/5 stars)
The result? A driver in the Renault could go out on his own from the car. The Volvo driver...well, would have several damages in his legs and would need some help to get out of the car.
The older large cars and almost all trucks, vans, and SUVs often have much poorer crumple zone designs than modern passenger cars. Passenger cars are built to tougher standards than SUVs. The g-force experienced by an occupant of an SUV can frequently exceed the g-force experienced by an occupant of a car, particularly if both are driven into a fixed obstacle.
Your ball analogy is confusing momentum with forces seen by the passenger during impact. The more rigid the balls are, the effectively momentum will be transferred. The goal in a car accident, is to absorb the momentum in the body of the car. You don't want the rapid change in momentum to be absorbed by the passenger or the passenger compartment. In car accident terms, when the 1lb ball hits the 2lb ball, you want both to stop. How quickly each comes to rest is governed how each absorbs the impact. If the 1lb ball is a car, then the crumple zone is designed to absorb the impact. This reduces impact felt by the occupants. If the 2lb ball is something really stiff, like a big block of steel, then the entire force for the impact is transmitted directly to the occupant. This is really bad.
Incidentally, this is why the newer SUVs and pickups have crumple zones, and crush up like the small cars do now. You want the vehicle to take the impact, not the occupant. Nevertheless, SUVs are often made to truck standards, not passenger car standards, and frequently passenger cars have many more passenger protecting features.
My Geo Metro has a 51Hp engine, gets 50 MPG, and cruses at 75 MPG on the highway. I live at 9000 ft elevation and commute down a mountain to 4500 at steep grades. It goes as fast as you'd want to on mountain roads with 3-4 passengers. Yes its no drag racer, but it goes from pt. A to B efficiently and reliably. Besides it cost me 1/10th of a hybrid and gets the same milage. We love it.
Now imagine making it lighter and hybrid. No Doubt 20 Hp is sufficient.
If you go side-to-side, sure. If you go top to bottom, you're looking at closer to 7. But then of course there's Scotland stuck on top of England. According to the AA's (like the AAA) route planner, driving from Dover (major port in the South of England) to Aberdeen (city in the North of Scotland) takes 11 hours. But we English don't just drive to Scotland (and Wales, that's on the same island too!), we have ferries and trains to continental Europe. People regularly drive to the continent.
I've toured Europe in a Ford Sierra (a "UK big car" or "US mid-sized car" from the 80s/90s - this was a while ago), with a family of 4 and luggage for a 3 week camping holiday. Plenty of driving for double-digit hours. It's rather trivial to accept your dare, as I've already been there and done that. I can tell you from first-hand experience of long journeys (even by US standards) that cars of that size are fine for families.
This will really freak you out: I've done the same with family of 3 in a Peugeot 205, which is what you'd probably call a subcompact. Not especially comfortable, but far from unbearable.
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