Efficiency? Think Racing Cars, Not Hybrids 1320
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?"
Two things (Score:3, Informative)
Re:Seriously? (Score:4, Informative)
Re:In the US no one wants to buy light cars (Score:5, Informative)
Re:Seriously? (Score:3, Informative)
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.
Why the safety assumption? (Score:1, Informative)
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.
Lotus Elise (Score:5, Informative)
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 it's actually better (Score:4, Informative)
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.
Re:Who knew? (Score:4, Informative)
Kammback (Score:5, Informative)
Re:The Saturn Philiosophy (Score:1, Informative)
Re:Two things (Score:4, Informative)
For comparison, the drag coefficient of a water droplet is 0.04, a Honda Prius is 0.24, an H2 Hummer is 0.57 and an open parachute is 1.75. Smaller numbers represent less drag, obviously.
Here are a couple articles about cars that have been designed to be shaped like water droplets, one from Mechanical Engineering Magazine [memagazine.org] and one from from Popular Science [popsci.com]
Re:In the US no one wants to buy light cars (Score:2, Informative)
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?
Re:In the US no one wants to buy light cars (Score:5, Informative)
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...
Re:In the US no one wants to buy light cars (Score:5, Informative)
Re:In the US no one wants to buy light cars (Score:2, Informative)
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.
Re:Why the safety assumption? (Score:5, Informative)
Unfortunately it's not a myth, and it wasn't created by marketing.
The crash compatibility topic (big car vs. small car) was first brought up by the Insurance Institute for Highway Safety in a 1998 news release that stated:
The basic findings reinforce whatâ(TM)s long been known about vehicle size and occupant death rates. As vehicle weight decreases, the number of occupants killed in crashes increases.
and
Lighter vehicles have higher occupant death rates in two-vehicle crashes, and within each weight class, cars and pickups have similar occupant death rates.
Here is the link http://www.iihs.org/news/1998/iihs_news_021098.pdf [iihs.org]
Re:Regenerative Brakes (Score:1, Informative)
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).
Re:Regenerative Brakes (Score:2, Informative)
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.
Re:In the US no one wants to buy light cars (Score:5, Informative)
he's an F1 designer (Score:3, Informative)
Re:Why the safety assumption? (Score:4, Informative)
Re:In the US no one wants to buy light cars (Score:3, Informative)
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?
Re:In the US no one wants to buy light cars (Score:3, Informative)
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)
Re:In the US no one wants to buy light cars (Score:1, Informative)
*Laws vary from state to state, but most states have a law that says that bikes have the same rights/responsibilitys as cars.
Re:Create a new thing: A Commuter Car (Score:2, Informative)
Re:Two things (Score:4, Informative)
Actually, the Kammback [wikipedia.org] is better than a teardrop, aerodynamically and functionally. It's more aerodynamic, because it still has the same smooth flow as a teardrop, but it doesn't have all the surface drag. It's more functional because it's shaped more like a box.
We're already seeing lots of them. Expect more.
Re:In the US no one wants to buy light cars (Score:5, Informative)
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.
Re:In the US no one wants to buy light cars (Score:5, Informative)
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.
Re:In the US no one wants to buy light cars (Score:3, Informative)
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
Re:Two things (Score:1, Informative)
You are quite wrong.
Sincerely,
Someone who knows aerodynamics.
P.S. On a bicycle, at 20mph, 80% of the work done by the cyclist is done to fight aerodynamic drag. The other 20% goes to inefficiencies and rolling resistance. More goes to fighting weight(due to gravity) on uphill slopes.
Aerodynamic drag is huge on a car. At 35mph, where is the power going? Rolling resistance? Friction in the drive system? It mostly goes to drag. The only other large factor is weight, which takes effect mostly during acceleration.
Center of mass, manuverabilty (Score:4, Informative)
Re:In the US no one wants to buy light cars (Score:5, Informative)
Re:Who knew? (Score:1, Informative)
From Weather.com
Average weather in Washington DC
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/USDC0001?from=search [weather.com]
Yearly spread - 61 degrees farenheit
Average weather in Chicago Illinois
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/USIL0225?from=search [weather.com]
Yearly spread - 66 degrees farenheit
Average weather in KC Kansas
http://www.weather.com/weather/wxclimatology/monthly/graph/USKS0298?from=36hr_bottomnav_undeclared [weather.com]
Yearly spread - 69 degrees farenheit
Average weather in Dallas Texas
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/USTX0327?from=search [weather.com]
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 [weather.com]
Yearly spread - 41 degrees farenheit
Average weather in Berlin, Germany
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/GMXX0007?from=search [weather.com]
Yearly spread - 48 degrees farenheit
Average weather in Madrid, Spain
http://www.weather.com/outlook/travel/businesstraveler/wxclimatology/monthly/graph/SPXX0050?from=search [weather.com]
Yearly spread - 58 degrees farenheit
(No average information available for London, UK)
ABIL
Re:In the US no one wants to buy light cars (Score:5, Informative)
Not only that, but Murray also worked to finalize the design of the (already nearly complete) Caparo T1 [wikipedia.org], which is even quicker (0-60 in 2.5 seconds), and with less horsepower than the F1. How? It weighs about half a ton.
Re:In the US no one wants to buy light cars (Score:2, Informative)
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.
Flawed basis for a conclusion. (Score:3, Informative)
(newer study: http://www.iihs.org/sr/pdfs/sr4003.pdf [iihs.org])
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.
Re:In the US no one wants to buy light cars (Score:5, Informative)
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.
Re:In the US no one wants to buy light cars (Score:3, Informative)
Re:In the US no one wants to buy light cars (Score:2, Informative)
A different hybrid drive train can lower weight (Score:5, Informative)
Re:In the US no one wants to buy light cars (Score:3, Informative)
Re:SUV's not going anywhere (Score:3, Informative)
Something like one of these: http://www.citroen.co.uk/new-vans [citroen.co.uk] -- probably from the first two rows.
Re:In the US no one wants to buy light cars (Score:1, Informative)
Re:Partially right... (Score:1, Informative)
Sadly, nearly everyone thinks that [wikipedia.org].
You're still blocking everyone else's line of sight.
Re:A different hybrid drive train can lower weight (Score:5, Informative)
I'd size it a little bigger than that, unless you can really cut down on weight. 70mph up a 15% grade is 4.7m/s of vertical lift. If the car weighs 1000kg, that's 61hp [google.com], not counting air drag or rolling resistance.
Re:Water Powered Car - no joke! (Score:4, Informative)
Re:A different hybrid drive train can lower weight (Score:5, Informative)
Re:In the US no one wants to buy light cars (Score:3, Informative)
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.
Re:In the US no one wants to buy light cars (Score:3, Informative)
Re:In the US no one wants to buy light cars (Score:5, Informative)
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 [youtube.com] of Formula 1 Car vs Ferrari 550 Maranello vs Fiat road car.
Re:In the US no one wants to buy light cars (Score:4, Informative)
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.
Re:In the US no one wants to buy light cars (Score:5, Informative)
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.
And then watch this... (Score:3, Informative)
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.
Bigger Car does not mean less g-force (Score:3, Informative)
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.
Geo metro only has a 51 Hp engine (Score:4, Informative)
Now imagine making it lighter and hybrid. No Doubt 20 Hp is sufficient.
Re:Comparing Apples to Oranges (Score:3, Informative)
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.