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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?"
Because they're afraid they'll be crushed to a fine pulp when they get hit by a big honking SUV.
People are still buying SUVs, and really, I still prefer the idea of an SUV than a minivan or station wagon to try and haul people/stuff around. Maybe I'd feel different if I had a few children to get in and out, but I don't see the SUV going away anytime soon. Plus why not just make a lighter SUV?
I will shred my adversaries. Pull their eyes out just enough to turn them towards their mewing, mutilated faces. Illyria
... but how many coconuts can an SUV carry?
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.
I'm just saying...
It might be helpful.
So aerodynamics and weight make a difference when trying to propel an object?!
This is going to revolutionize everything!
Maybe if we drove cars in space we wouldn't have those pesky problems.
I have spoken'eth.
I like bigger autos. I'm 6'3" with a family history of back problems. I DON'T want a car, I want a fuel-efficient pickup/SUV/Crossover that doesn't bounce around like a jeep and I don't have to deal with the up-and-down motion of getting in and out of. I like hauling crap around. I like being able to see OVER traffic.
GM is on the right path with the Hybrid Silverado they are making, but I would like to see something a little smaller, along the lines of a Ranger or S-10/Sonoma (I LOVED the 1994 Sonoma I drove through college). Americans are going to buy small cars in the near future, but the REAL money will be made when we can drive larger SUV's and trucks that get 30+ MPG's.
Lighter cars use less gas? What's next? Telling people that they shouldn't live 200 miles from where they work? I heard a kind of a funny fact this morning on BBC, average energy consumption per capita in North America is double that in Europe. It's not like the standard of living or climate is that much different, it's all about the culture.
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.
Hybrids get their benefits in two ways: reclaiming power that would otherwise be lost during braking, and the fact that electric motors have a flat torque band. You generally can't do either that with an internal combustion engine alone.
However, there are a few ways to do both the above without an electric motor. One way is to have a flywheel connected to a CVT on the drive shaft. When you hit the brakes, the flywheel spins up. You can then release that power again when you accelerate. The flywheel will also act as a gyroscope, so you need to have some way of tilting it so you can go through corners with it spun up (which has the side effect of increasing handling). This method is being put on F1 cars soon.
The other way is to have an air compressor, which again is run off the drive shaft when you hit the brakes. On acceleration, the compressed air could either run the drive shaft, be dumped into the intake to increase boost, or dumped into the exhaust manifold to eliminate turbo lag. This is probably easier to design than a tilting-flywheel system, though it won't make handling better.
The compressor could also run off turbines using inlets around the car's body that are opened when braking. This particular use is probably illegal for F1 and other types of race cars (which often ban variable body shape systems), but could easily be used in road cars.
Both the above don't require any particularly exotic materials (though carbon fiber or nanotubes would be nice for the flywheel), and shouldn't be as heavy as an electric motor/battery system.
Not a typewriter
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.
I bike commute to work, and the only close shave I've had is with the new Gillette Fusion(r) Power razor. Truly, the best a man can get.
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
These comments are my own and do not necessarily reflect the views or opinions of my employer or colleagues...
- One that I only drive to and from work, maybe grab a 12-pak of Diet Dr Pepper®
- One that has ONE seat, maybe 2 in tandem for carpooling, thus a narrower front for lower drag coefficient, maybe a tripod
- One that gets a55-load MPG, on regular gas
- One that is enclosed against rain, maybe even snow.
- save weight by removing the automatic transmission, power steering, power brakes, Bose Stereo, the GPS, the air bags, spare tire. Make the tank small enough to weigh little and still get me through the work week without refilling
- Actually, remove ALL safety features except the brakes and the brake lights! Save weight. no OnStar, no Lojack, no side curtains.
- Cut us some slack on emissions. Yes, commuters are the bulk of the problem, but not if we are burning half of the fuel that we would have been.
- it has to be CHEAP! Like $2000. Cheap to insure. Cheap to replace panels if we bump each other. Easy to park.
- if you want to get REALLY froggy, give us tax breaks, or our own LANE on the freeway. Watch people buy em like hotcakes.
Ok, so I just described a 1982 Suzuki, full face helmet and a rain suit, except for the 3-wheel stance.My point is really this. We need a small, commuter-only vehicle, unfettered from the legal burdens that add weight and reduce gas mileage. And yet still capable of highway speed and 200 mile range. Take an F1 car, make it 3-wheeled with a Jet cockpit. End of problem. It's not rocket science...
What about not driving absolutely everywhere? I see a lot of people drive from my apartment complex to the convenience store next to it. Total time to walk is about 2 minutes. When you add up going to the underground parking, starting your car, exiting the underground parking, waiting for traffic to turn onto the main road, drive down 30 feet of road, and then wait for traffic again as you drive into the parking lot of the store. It takes more time to just get to the store than if you walk. Sure that short drive isn't going to cost too much in gas, or cause too much harm to the environment, but the whole attitude of having to drive absolute everywhere is just terrible.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
I don't know about you but most of the SUVs I've ever seen have carried little more than the drivers fattened ass and a few sacks of groceries.
Dedicated Cthulhu Cultist since 4523 BC.
And of course you're inferring a causal relation from a correlation. None of those quoted statements take into account specific circumstances. Do people speed more in smaller cars than in large SUVs, thus leading to more accidents? Are people more likely to switch lanes more quickly in smaller cars than in large ones? Smaller cars also accelerate faster than SUVs, so at intersections the small cars will be the first into the intersection after a light turns green. None of these things are taken into account.
If you want to give up weight in cars.
a) get rid of the catalytic converter
b) shorten the tailpipe and shrink the muffler
c) get rid of airbags
d) get rid of power heated super seats
e) get rid of side impact safety beams
that right there gets you some good weight savings.
This is my sig.
"A closed mind is a good thing to lose"
Main Website: http://waterpoweredcar.com/
Videos:
Genius US Inventor (water car): http://www.youtube.com/watch?v=KZOsOB3z3IE
From Australia: http://www.youtube.com/watch?v=IXzK-zrWDgI&feature=related
Water Car Inventor Murdered -news channel report: http://www.youtube.com/watch?v=L6yRn4IAsrU&feature=related
Ford Conversion: http://www.youtube.com/watch?v=-piMEZ2WcQU&feature=related
From Japan: http://www.youtube.com/watch?v=E1OWDcWoXHs&feature=related
Company selling water cars: http://www.youtube.com/watch?v=C4mz7MPSquU&feature=related
WAKE UP AMERICA, your government lies to you! Well, ok, so does every other government, but this particular issue (water car) is worth fighting for.
No trees were killed in the making of this post; however, many trillions of electrons were horribly inconvenienced.
SUV are much, much worse at avoiding collisions, and are more likely to be involved in accidents per driver miles.
..........FULL STOP.
Playing somewhat of the devil's advocate here, but it's been pointed out several times that increases in vehicle weight are directly caused by extra safety features. I'd say this is a prime example of correlation not equaling causation. What you're looking at is lighter vehicles that are lighter due to being older and lacking safety features, thus being less safe. Higher death rates aren't a function of weight, but a function of safety features (that is, the lack thereof). It simply happens that those safety features make a vehicle heavier, hence the correlation of lighter = less safe.
That doesn't mean that lack of weight is fundamentally unsafe, just that we need to reduce the weight of all those safety features (and the rest of the car, while we're at it) without compromising, uh, safety. Probably a tall order tho.
Nobody expects the British Columbia Human Rights Tribunal.
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.
Smart car crash test...
http://pl.youtube.com/watch?v=Y1NHXiGd0rQ
Which driver suffered more?
No sig today...
In case anyone actually believes this: http://en.wikipedia.org/wiki/Waterpowered_car Sorry to spoil your fun.
-Xoltri
I can assure you, living in the SE of the US, like in New Orleans, AC is not a luxury...pretty much a necessity if you wish to arrive at work, or anywhere else, and not look like a sweat soaked beggar. Most professional offices kind of frown on that.
Hell, down here...you turn on the AC at home basically in early April...and it really doesn't go off again till November.
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
problem is, this guy has no knowledge of real world driving, formula one cars spend all there energy accelerating and decelerating like crazy and have ridiculously low drag coefficients. Because of this weight effects them tremendously. Many times more than any average car.
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.