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The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

camarocarplace.com

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Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#41

Post by ForHackernews »

jerf wrote: post #38
onion2k wrote: post #36

Earlier quoted context omitted.

It does have something to do with cars - it shows that if we changed our requirements we could be driving much more efficient cars. Even if safety and comfort meant than we could only get 1/10th of the demonstration, that'd still be a good deal better than what we have now.

You need to drop a lot of the safety, grossly raise the price, or both though. I've got some family in the auto industry, and their consensus is that we are either really rapidly coming up on the point where we've got just about all the safety and fuel economy we can have without sacrificing safety, or we're already there. You're getting into the space where arguing for increased fuel economy is going to be directly…

If we have self-driving cars that are dramatically less likely to be involved in accidents, then we can start relaxing the safety requirements.

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#42

Post by sigzero »

onion2k wrote: post #40
jerf wrote: post #38

Earlier quoted context omitted.

You need to drop a lot of the safety, grossly raise the price, or both though. I've got some family in the auto industry, and their consensus is that we are either really rapidly coming up on the point where we've got just about all the safety and fuel economy we can have without sacrificing safety, or we're already there. You're getting into the space where arguing for increased fuel economy is going to be directly…

I don't have any family with a vested interested so perhaps I can be more impartial. ;) There is a very straightforward way to make cars both more efficient and safer - make them smaller and lighter. Then they'll require less energy to move around and they'll have less energy if they hit things. The challenge to overcome is that driving a small and light car is actually more dangerous while big and heavy cars are sti…

"smaller and lighter" means more deaths when not all the potential impact cars are not also "smaller and lighter".

Also, "smaller and lighter" and certainly what they used in the test isn't FAMILY practical.

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#44

Post by Jach »

001sky wrote: post #29
papa_bear wrote: post #2

Very cool car, very poor quality article. It reads like it was written by a syndication algorithm that throws in weirdly subjective statements at the end of every paragraph. Here's a slightly better one with a video: http://wonderfulengineering.com/new-car-designed-by-french-s...

Ha. Its not even a car - it's a tricycle[1] ! The distinctin may sound pedantic but legally speaking they are quite distinct: It’s lack of a four wheel, and low production volume, exempt the Morgan from most safety and emissions regulations. At least in the US...Quite Ironic. [1] see, eg> http://www.digitaltrends.com/cars/morgan-three-wheeler-is-it...

The Aptera http://en.wikipedia.org/wiki/Aptera_2_Series (RIP) may be a better example, it's generally classified as a motorcycle in US states but since it's enclosed a helmet or motorcycle license isn't necessary.

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#45

Post by jerf »

onion2k wrote: post #40
jerf wrote: post #38

Earlier quoted context omitted.

You need to drop a lot of the safety, grossly raise the price, or both though. I've got some family in the auto industry, and their consensus is that we are either really rapidly coming up on the point where we've got just about all the safety and fuel economy we can have without sacrificing safety, or we're already there. You're getting into the space where arguing for increased fuel economy is going to be directly…

I don't have any family with a vested interested so perhaps I can be more impartial. ;) There is a very straightforward way to make cars both more efficient and safer - make them smaller and lighter. Then they'll require less energy to move around and they'll have less energy if they hit things. The challenge to overcome is that driving a small and light car is actually more dangerous while big and heavy cars are sti…

I don't have a vested interest either; I don't work in the industry myself. What I have is a bit of a view into just how far down the road we are on the engineering tradeoffs already.

Small and light cars aren't a miracle cure anyhow. It's amazing how small the gains are from shrinking a car. Yes, there are gains, but we're not talking taking a 40mpg sedan (in routine manufacturing now, BTW) and turning it into an 80mpg sedan "just by shrinking it a bit". You might get it down to 50mpg, but, per other articles observing that "mpg" is the wrong way to view it and "gallons per mile" starts making more sense, a 40 to 50 mpg gain is not actually that large.

No, the environment can't be saved just by "making cars smaller". You don't win anywhere near as much as you think, because of the way drag works (it's nonlinear in speed). And you can't just start taking panels off and stripping out airbags.

From what I gather, having trimmed just about everything they can from the spare tire, they're on the verge of dropping it off entirely. That's the level of optimization we're down to. There isn't much left after that. The seats are what they are due to safety regulations. The airbags are there because of safety regulations. The bumpers are there due to safety regulations. The body panels are what they are due to safety regulations and the need to survive a certain number of years out in the elements. There's just not much freedom in car design anymore.

My family doesn't include designers in them, but they relayed the designer's complaints to me that the constraints are becoming so strong that it's becoming very difficult to differentiate between cars anymore. If it feels like they all look the same lately, excepting perhaps the exact location or shape of the lights, it's because they do look the same; the combination of safety and efficiency regulations is rapidly converging down to one solution for a given form factor. Again... this is the sign of an optimization process reaching its Pareto frontier, and that you can't get big gains anymore without big sacrifices somewhere else.

You can look out in the world and see that last bit of evidence yourself, without anyone in the automotive industry. It's the same systems optimization problem faced by any engineer, even programmers.

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#46

Post by jerf »

ForHackernews wrote: post #41
jerf wrote: post #38

Earlier quoted context omitted.

You need to drop a lot of the safety, grossly raise the price, or both though. I've got some family in the auto industry, and their consensus is that we are either really rapidly coming up on the point where we've got just about all the safety and fuel economy we can have without sacrificing safety, or we're already there. You're getting into the space where arguing for increased fuel economy is going to be directly…

If we have self-driving cars that are dramatically less likely to be involved in accidents, then we can start relaxing the safety requirements.

Yes, this truly is the phase change that will get us out of this hole. Self-driving cars could also practically use battery-switch-out technology and very rich rental models where we don't all have to own our own cars anymore, reducing the actual cost of manufacturing by making fewer cars, another big win that you simply can't optimize the current system into.

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#47

Post by fractallyte »

corin_ wrote: post #39
001sky wrote: post #29

Earlier quoted context omitted.

Ha. Its not even a car - it's a tricycle[1] ! The distinctin may sound pedantic but legally speaking they are quite distinct: It’s lack of a four wheel, and low production volume, exempt the Morgan from most safety and emissions regulations. At least in the US...Quite Ironic. [1] see, eg> http://www.digitaltrends.com/cars/morgan-three-wheeler-is-it...

There may be legal differences between types of car, but I don't see why three wheels should make it "not even a car". For example in the UK we had a mass-market three wheeler called the Reliant Robin, which was culturally considered to absolutely be a car (albeit a car worthy of having jokes made about it). http://en.wikipedia.org/wiki/Reliant_Robin

I prefer the Bond Bug as the exemplar of classic three-wheel design ;-)

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

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#48

Post by 001sky »

corin_ wrote: post #39
001sky wrote: post #29

Earlier quoted context omitted.

Ha. Its not even a car - it's a tricycle[1] ! The distinctin may sound pedantic but legally speaking they are quite distinct: It’s lack of a four wheel, and low production volume, exempt the Morgan from most safety and emissions regulations. At least in the US...Quite Ironic. [1] see, eg> http://www.digitaltrends.com/cars/morgan-three-wheeler-is-it...

There may be legal differences between types of car, but I don't see why three wheels should make it "not even a car". For example in the UK we had a mass-market three wheeler called the Reliant Robin, which was culturally considered to absolutely be a car (albeit a car worthy of having jokes made about it). http://en.wikipedia.org/wiki/Reliant_Robin

From your citation:

It is markedly different from most mainstream cars due to its fibreglass bodyshell and compact three-wheeled platform which allow it a special taxation and licensing class under British regulations.

Also, the Morgan I linked to is British and is very capable--far more so--as a piece of engineering.

My guess is that three-wheel regulations were originally set up for motor-cycles with side-car. These evolved a seperate lineage of both engineering and regulation. For modern examples, see: Can-Am Spyder.

Re: The most fuel efficient car ever built: 2072 miles with 1 liter of fuel

#49

Post by chrismcb »

utopkara wrote: post #32
nileshtrivedi wrote: post #14

Here are the detailed results of the contest (and yes, the original results are in km/l): http://s08.static-shell.com/content/dam/shell-new/local/corp...

There are more than ten contestants who beat 1000 km/l. That's a lot of contestants ignored by an article about a research contest. Without getting into a long argument about how science and collaboration works, narrow sighted articles that cover events like this do a lot of damage.

To be honest with you, even the second place was not even close to this car. In all seriousness though, the top car beat the 2nd place vehicle by 50%. While the other vehicles were impressive (even the last place one achieved 200+ mpg) this one was much more impressive than all the rest (yes it is!) I'm not sure what damage you think this article is going to do.
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