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Eco-Marathon Team Hits 2,843 mpg
At this year's Shell Eco-marathon Americas event the team from Mater Dei High School shattered last year's record by traveling 2,843.4 miles on a single gallon of gasoline. "How did the Evansville, Ind., team come up with its winning airfoil-meets-teardrop design and beat out its largely collegiate competitors? "It comes from trial and error, seeing what works and what doesn't," an unidentified student and team member told a local newscaster Friday. Those top three vehicles, like most in the competition (25 out of 33 total), used internal combustion engines. The goal for all entrants was to travel as far as possible using as little fuel as possible. Vehicles--sans driver--couldn't weigh more than 160 kilograms (352 pounds), while drivers had to weigh at least 50 kilograms."
It's not supposed to be for production, numb-nuts. Forumla 1 racers don't have AM radios, either, nor power windows. They must suck, eh?
Anyhow, I was wondering why there is an upper limit on weight in this contest? It seems like it's harder to get good mileage in a heavier car, so what gives with that?
Currently hooked on AMP
I don't understand why modern cars get such lousy mileage.
Air conditioning, for one thing.
If I have been able to see further than others, it is because I bought a pair of binoculars.
it's easier to claim thousands of miles per gallon on such small vehicles than it is for a typical car. "we got 3,000 miles per gallon!" sounds far more impressive than "we got 100 miles per gallon" even though 100 mpg is amazing in of its self they are looking for overkill.
Sigs are too short to say anything truly profound so read the above post instead.
How do you measure miles per gallon on a non-gasoline-powered vehicle?
Because both vehicles' power can be measure in watts, e.g. a gallon of gas contains around 60 kilowatt-hours of chemical energy.
I said no... but I missed and it came out yes.
According to this video that's almost 10 times farther than a person could walk on a gallon of gasoline... if a person could metabolize gasoline, of course.
- Greg
Start a happiness pandemic
Well, to start with, the anti-pollution devices don't make the engine more efficient. They eliminate unburned hydrocarbons and nitrous oxides. Sometimes these anti-pollution systems actually use available horsepower to do their jobs. In some cases they reduce the efficiency of the engine, in order to reduce emissions.
One good example is the catalytic converter. It is in the exhaust stream, post combustion (usually mounted under the floor of the car). It works by catalytically combining oxygen, often pumped in, with any unburned hydrocarbon (CO, for example). Having the catalytic converter in the exhaust system acts as a restriction. So, it requires power to pump the oxygen it needs to do it's job, and it reduces the engines efficiency by increasing back-pressure.
I think you get the idea. I've read that the pollution control hardware costs the typical vehicle a couple of miles-per-gallon in efficiency
As to no longer needing them, once you improve the efficiency... Well, now that the laws are in place requiring the emission control systems to be included, it's always harder to undo a law, so there will be very little effort in that reguard. No politician wants to be known as the one who submitted the bill to remove the emission control devices. Particularly in today's political climate. In fact, the trend is to go the other way: If the engine becomes more efficient then the emission control system should be able to remove even more unburned hydrocarbons and nitrous oxides; and, the requirements therefore become stricter.
How about a contest where the results can actually benefit a normal car?
http://www.progressiveautoxprize.org/
And adjusted their carburetor. Now it only gets 30 Miles per gallon.
Don't you mean the EPA showed up and made them meet air quality controls?
You're right, the weight that cars have gained has not been because of the engines, but the other poster never said that it was. He said that engine sizes have increased, and he's right. The additional weight has resulted in a significant increase in the sizes of the engines to compensate for the added weight while maintaining or increasing performance. So yes, the increased fuel consumption is because of bigger engines. The bigger engines, in turn, are because of the increased weight.
So I wouldn't say his guess sucks. It sounds like it was right on, he just neglected to boil it down to the root cause. You're both right.
Random and weird software I've written.
That may be true, but it's still a pretty meaningless number if you're not actually consuming gasoline. I could measure the power consumption based off the number of candles it takes to power a steam-based generator, but that would be equally stupid. Like the ongoing "Libraries of Congress" thing.
If you're going to use an indirect unit of measure to determine the vehicle's efficiency, surely you'd be better off with pounds of CO2 as a waste-product of the energy production to power the vehicle for an hour. Or something like that.
How are sites slashdotted when nobody reads TFAs?
There are many ways to be more efficient - more complete combustion is only one. Better heat transfer, less wind resistance, less weight, etc. all make a more "efficient" vehicle without necessarily more complete combustion. This is why a Hummer may pass a emissions test getting 10 mpg while an old Civic fails getting 30 mpg. The Hummer removes all the unburnt hydrocarbons and passes while the old Civic releases them into the air and fails - even if the Hummer actually produced more. They are not testing efficiency, only how well the vehicle handles its emissions (and only a few - if they measured CO2 output then the Civic would perform much better than the Hummer). The necessary components required to scrub the exhaust adds weight and reduces power output (as does a muffler - but I think those are here to stay).
Why waste time building it?
Because we LEARN. How many great scientific/engineering breakthroughs were preceeded by someone saying "don't waste your time on that"?
"Strange how much human accomplishment and progress comes from contemplation of the irrelevant."
- Scott Kim
Can we get a "-1 Wrong" moderation option?
It's fundamentally not a fair comparison. For example, per kilogram, hydrogen has a lot more energy than gasoline. And fuel cells are more efficient than internal combustion engines. Of course, to make that hydrogen, a lot more energy was wasted than when making gasoline. And that hydrogen is bulky, hitting range. But that wouldn't hurt it here; by your rules, hydrogen vehicles would win easily.
Anyways: to those who think these vehicles are whimsical and whose tech can't readily be applied to streetlegal cars: As I posted over on Autobloggreen.com, compare This eco-marathon winner with this car due out this fall.
Of course, you see the problems with commercializing these eco-racers as-is. They're not stable enough for high speeds (hence Aptera's need to broaden the front wheelbase, increasing the drag coeff, as well as wider tires for better handling), there's too much ground turbulence at high speeds (hence the higher body), they're not comfortable for passengers (hence the larger cross section), and they're not streetlegal (hence things like the truncated, not-completely-tapered tail). Also, there's the fact that by their very nature, things like "normal driving cycles" and "highway speeds" greatly increase drag. And all of this adds weight, too. Hence, "thousands of miles per gallon" turns into "130 miles per gallon" (in the Typ-1h). Still impressive, mind you.
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
It depends on a lot more then vehicle speed. Inaccurate blanket statements are an issue with mythbusters. Their conclusion is obviously constrained by several parameters including, but not limited to, wind spd, wind dir, vehicle geometry, AC size, AC COPR, AC control, temp, humidity, etc. Many of these may very well change the conclusion by less than 10%, while others have a serious influence. In any event, five 5 percents add up. That's my problem with mythbusters, they take the most laborious(boring) yet critical component out of experimentation: defining the problem & methodology. This is a good example because the conclusion is essentially worthless. Rather then celebrate science, they completely miss the point.
Its Shell sponsoring it, of course non-gasoline vehicles weren't eligible for the grand prize...
Damn corporate scams for cheap publicity and easy recruitment.
Hey, now, let's put this conspiracy theory through it's paces. So, Shell is hosting this competition for cheap publicity and easy recruitment, right? Then why would they rig the race -- the ultimate example of trying to earn bad publicity and discouraging recruitment? Or, if the rigging was hoping to promote gasoline while they still get cheap publicity and easy recruitment, by trying to imply that gasoline always wins or something (I'm trying to help your theory out here), then why did they allow other fuels compete at all? To make gasoline look bad so that they can then refuse to award them the prize?
It just doesn't make sense.
Look, oil companies have done a lot of bad things in the world -- some intentional, most unintentional, but still bad. But pretending that *everything* they do must have some sort of evil hidden motive to keep the world addicted to gasoline is just ridiculous. The other day, I sat down on a park bench that had a small plaque on the side that it had been donated by Shell. Clearly, that bench was an insidious attempt to get Americans to stop walking so that they become fat and lazy and need big SUVs to support their exercise-averse lifestyle, right?
Things like this serve many purposes. Some of them can get tax deductions. Some of them are an attempt to earn good PR or recruit. Some of them are, to be quite honest, a way to allow execs to feel all warm and fuzzy that they're doing good things in the world while they keep the oil flowing. But the concept that everything they do must be a plot to keep us hooked on gasoline is just dumb.
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
I want some technical details. Instructions on how to build my own. Hell it didn't even say how fast they were going. Where the juicy information?
Right, it's because of McDonald's drive-throughs that cars are heavier. Well, when people are *in* them.
Random Thoughts From A Diseased Mind (Not For Dummies)
Troll is full of shit? CORRECT.
The enemies of Democracy are
You can't outright discount gasoline, though. Gasoline engine innovations are quite important right now, where relatively few reliable sources for on-the-go alternative energy exist.
Given that the distribution systems for gasoline are already well in place, an efficient petrol-burner may end up being a far better ecological and conservational option than even a more efficient alternative-energy car. If a car can't fit into the budget and lifestyle of a large enough group of people-- as well as be successfully marketed and sold as such-- it won't have the adoption to support its production, and have as little real impact as if it was never made.
Information wants to be free.
Entertainment wants to be paid.
You just want to be cheap.
You sir, I point to xkcd.
Mmmmm... Zombie Feynman.
Are you a physicist, perchance?