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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."
And adjusted their carburetor. Now it only gets 30 Miles per gallon.
What It could happen...
Ask not what you can do for your country. Ask what your country did to you
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
My 1963 car gets 40mpg. Sure it's an 2-cylinder NSU Sport Prinz but even the 1960s Darts I've had got 25-30mpg with a slant six.
I don't understand why modern cars get such lousy mileage.
riding round the world on an old motorcycle
Let us briefly pause whilst my 1988 Mercury Grand Marquis sputters loudly with contempt.
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.
What's the conversion so that solar cars can get "MPG" of gasoline?
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.
The implication is that the achievement is not a matter of fuel/applied power efficiency alone. If the primary reason (most of these) contests exist is relegated to an afterthought, the arbitrary rules that allow for such a minimal design seem silly. Why isn't the car tested in a lab if you're going to remove it from the realm of real application anyways? What's the point if not a theoretical application of minimalism in a controlled environment? If you want a fuel efficiency competition you probably don't want it to be influenced by the rule of thumb that the mass of the car can be shrunk. When you get a 4-runner to go 1000 miles on a gallon of gas, I'll take notice. Till then, these competitions are relatively pointless imo.
Often wrong but never in doubt.
I am Jack9.
Everyone knows me.
How do you measure miles per gallon on a non-gasoline-powered vehicle?
I've heard this accusation before, but I don't grok it at all. My limited understanding was that anti-pollution devices were supposed to squelch unburned hydrocarbons emitted by inefficient engines. However, if your engine is more efficient -- if it more completely burns hydrocarbons -- then the emissions controls should be superfluous.
Could you explain this to me? In concrete terms, how are contemporary emissions controls impeding the development and release of more efficient vehicles?
Schwab
Editor, A1-AAA AmeriCaptions
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.
Just imagine walking out to your car in the morning, getting in, turning the key, and kaboom!
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
Modern cars get better mileage with the windows rolled up and the AC on than with the with the AC off and the windows rolled down. Of course the best mileage is with the AC off and the windows up, but the passengers might be done to medium-well at the end of the trip.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
Weight.
Crash test standards add weight. Power windows, power-adjustable seating, 6-disc in-dash CD changers, power moonroof, they all add weight.
Colin Chapman, the founder of Lotus, pointed out that "Adding power makes you faster on the straights. Subtracting weight makes you faster everywhere." He was going for speed, but the same thing applies to fuel economy.
Consider a car that's a lot newer than those you mention: the 1985 Honda CRX. It had a 76-horsepower engine, and it had a 9.1-second 0-60, and 32 miles to the gallon. It was able to do that because it only weighed 1860 pounds.
1860's unthinkably light by current standards. I drive a Mustang GT that has a curb weight of something like 3860 pounds, so that's more than two tons with a driver and a tank of gas. You want a performance car that's even close to that 1860lbs, you end up with...a Lotus Exige, which is about 2000 lbs. And costs a hell of a lot more than an '85 CRX.
Yeah, your guess sucks. Advances in engine technology have been utterly remarkable over the past several decades, to the point where Honda can squeeze well over 200 horsepower out of a naturally-aspirated 2-liter 4-cylinder engine. Specific power has increased by incredible amounts since the cars the poster was referring to.
Cars have gained ridiculous amounts of weight since the 1960s, but that's not because of the engines.
Also, an essential strategy for achieving high mileage is to burn the engine at optimum efficiency RPMs to quickly get to speed, and then use your mass combined with low aerodynamic and rolling losses to coast as long as possible (frequently almost to the point of stopping). This is why there are required average lap speeds and maximum speeds. Of course, this strategy could hardly be used in production vehicles or in public roads.
Well, you could measure how far it could travel before the 1 gallon of gas eventually escaped from the walls of the gas tank.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
Second, modern cars have bigger engines. Even a tiny town car in Europe often now has a 100BHP engine when 20 years ago it would have been 60. More acceleration, more wasted power, plus the bigger engine just takes more power to turn over. Third, modern fuel has a lower octane rating than older fuel, and so must use a lower compression ratio - which means lower efficiency, as you find out in basic thermodynamics. Finally, air con,power steering, all need power to operate. Even the most basic model of possibly the most basic car in Europe - the Hyundia i10- has air con, power steering, and a 60HP plus engine.
Despite this, the best modern engines are remarkably good because of advances in fuel injection (both Diesel and gas), and because the timing cycles and better valve gear result in less port wastage. The real fuel consumption of that 2007 Diesel is about 80% of my 1990 non-turbo mechanically injected model of the same weight and size, which is pretty good.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
If you read the article, the top competitor using gasline got 163.5 MPG. It does say they used Internal Combustion Engines, and it doesn't say what they did use but it's not gasoline. It doesn't say whether that 2843 MPG is miles per gallon of some other fuel of if they gave them the engergy equivalent of 1 gas of gasoline in that "some other fuel" and measured how far they went on that. Or maybe it's something else completely. The article is poor on details.
Real programmers use "copy con program.exe"
That depends on your speed. Yes, I'm pulling out MythBusters because not only did they do this experiment, they went back and repeated it because they inadvertently screwed it up the first time.
The cut off point for when to use A/C or not is 50 mph. Below that, it is more efficient to leave the windows down than it is to use the A/C. Above that speed, the reverse is true.
How did they screw this up? They went 50 mph and tried things both ways. D'oh!
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
A heavier car is less susceptible to wind gusts. And drag isn't effected by weight, so the only downside to adding more weight is the initial cost of getting the thing moving.
Quid festinatio swallonis est aetherfuga inonusti?
Africus aut Europaeus?
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/
I have a 460hp (modded) car that got 38mpg on a LA-San Diego round trip. At the same time, it gets about 2mpg at full throttle and top speed. There is nothing wrong with modern engines, but if you have a ton of power and habitually use it, you will pay in fuel.
And do not forget, modern cars are heavier because of safety requirements, noise reduction materials, power everything, air conditioners, etc...
No good deed goes unpunished...
My Dad's old Corrolla would get 44mpg. He used to track it in his little notebook every time he filled up. It was carburated, 4-cylinder, seated 4, and ran over 200K miles before he sold it. How the hell do today's manufacturers get away with boasting/advertising 25mpg?
you've probably noticed already, but these are not practical vehicles. We're talking about single-person, prone-position, ground-hugging, 10-20 MPH vehicles. Of course you can get 2000+ MPG with those conditions! The Progressive Automotive X Prize is about practical vehicles getting 100 MPG (or equivalent). Now that's a race whose outcome is interesting! Check out some of the X Prize Cars which have already been designed.
augment your senses: http://sensebridge.net/
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).
Not really. The EPA tightened the restrictions on diesel emissions last year (2007). The Diesel technology to meet those requirements already existed, but the excessive amount of sulfer in US Diesel prevented those systems from being introduced here.
Also taking place in 2007 was the change over from Low Sulfur Diesel (LSD) to Ultra Low Sulfur Diesel (ULSD). Because of the time line of the USLD conversion you could still buy LSD up until October/November of 2007, and In theory, the tanks could have a LSD/ULSD mix there after if there was still some amount of LSD in the storage tanks when the first ULSD delivery came in.
So basically, due to really crappy timing on the EPA's part (that ironically enough helped the US manufacturers who had no light duty diesel options), there was only 1 light duty diesel that could be sold in the US through 2007.
But now it's 2008. ULSD is the only Diesel now. VW, Mercedes, Jeep, hell even Honda all have new light duty diesels either already out, or coming out in the US this year.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
The reporter got it wrong (as usual). The single entry was actually running Liquefied Petroleum Gas (LPG) not as he reports "liquid petroleum gasoline". I believe the "combustion" class of which the winner was a part is plain old gasoline, just as the headline states.
Not sure if the rule have changed or what, but my university (University of Saskatchewan) got 5691 mpg in the Shell Fuelathon back in 1986, and 3086 mpg at the SAE Michigan Super Mileage Competition the same year.
The vehicle weighed 84 lbs and used a 70cc engine.
http://engrwww.usask.ca/affiliation/societies/sae/history.html
In the diesel world fuel is required to burn off trapped hydrocarbons.
On all new 2007+ truck engines a Diesel Particulate Filter is required to trap diesel 'soot'. What happens when this filter gets full is fuel is injected to heat up the the element and burn off the soot.
Also if you run your engine TOO efficiently you create NOx (Oxides of Nitrogen), which is also regulated as an emission. So if you're at a low load condition (say idle) you could get away with burning 0.1 gal/hr. But you'd be spewing NOx, so instead you burn 0.2 gal/hr so that you have 0 NOx (but higher CO2, which is unregulated).
I don't know how it works for gasoline engines.
(Disclaimer, I work for one of the 'big 3' American diesel engine makers)
And drag isn't effected by weight, so the only downside to adding more weight is the initial cost of getting the thing moving.
On a flat Earth I would agree with you. However since the real world outside the lab has hills, I would say that adding more weight has a bit more downside than you think. Oh I agree there are devices that try to "harness" the energy from the downhill runs (and deceleration) via hydraulics or pneumatics, and "boost" the engine when needed (startup, uphill). And all self respecting scientists know that you will never approach 100% efficiency (40% being the theoretical max).
But you can't escape the m part of the F = ma formula.
Seven puppies were harmed during the making of this post.
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?
The catalytic converter, which is an important part of the emissions control systems in a car, sits in between the engine and the tailpipe. It contains a honeycomb structure coated in a catalyst. For it to work at any real effectiveness, the honeycomb must have many densely-packed chambers the exhaust gasses are forced through.
The catalytic converter is therefore an impedance to the flow of exhaust gasses. In a four-stroke engine the exhaust gasses are pushed out by an up-sweep of the piston. If you restrict the exhaust, the piston "feels" the resistance. Imagine plugging the tailpipe entirely - the result isn't what you'd call "efficient."
There are also a few other complexities introduced with catalytic converters, like the fact that it's much harder to burn fuel lean.
...12,665 MPG, achived by a Swiss Eco-marathon competitor in 2005. ( http://en.wikipedia.org/wiki/Eco-Marathon )
Gotta love this quote...
Shell points out that "it would be possible for the winning Shell Eco-Marathon UK car to travel three times around the equator on the same amount of fuel that Concorde needed to reach the end of the runway.
That that is is that that that that is not is not.
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!
From the article, drivers had to weight 110lbs or more, not less.
"The past was erased, the erasure was forgotten, the lie became truth." ~1984 George Orwell
Well, I can't point you to a vehicle a tenth as efficient, but this car due out later this year comes in two models -- the Aptera Typ-1h, which gets 130mpg plus has a 40 mile all-electric range, and the Typ-1e all-electric with a 120 mile range. Since power plants have a higher thermodynamic efficiency from burning fuel than gas engines, while battery, charger, and transmission losses are very small, you're looking at almost 200mpg equivalent for the Typ-1e and for the first 40 miles of the Typ-1h's range. So, you're looking at roughly a 20th as efficient, give or take in either direction. The price is a bit steep for a two seater ($30k for the Typ-1h and $27k for the Typ-1e), but when you're nearly or completely eliminating a couple thousand dollars in money spent on gasoline per year for a hundred dollars spent on electricity, and cutting maintenance (the electric drivetrain only has the following moving parts: three wheels, one drive belt, one sealed brushless electric motor; not even a transmission), you can hit payback pretty quickly, and certainly pay off the difference over a normal car in several years. Not to mention, it's all sorts of crazy neat features like in-seatbelt airbags (like small planes use -- they don't explode toward you, but upwards to be between you and the dash, shielding your whole body), StreetDeck (a nifty nav/entertainment system), camera situational awareness displays, and so on.
They're currently moving into their production facility, and plan to offer test drives and factory tours in 30 to 60 days.
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
Thanks for the results list...but the article doesn't say anything at all about the tech behind the cars. Bah.
Obligatory blog plug: http://www.caseybanner.ca/
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.
You might want to spend some more time under a car, or at least read the wikipedia page on catalytic converters or automotive lamda sensors.
... you're on the freeway, you're still getting better mileage. In the future if you're trying to convince people of negative effects of emissions systems, you may want to focus on added weight... or added expense, since the precious metals in the cat that are the catalyzing agents have to add a good $200+ to the cost of the car.
1. The resultant back-pressure from a cat is not significantly larger than that from a stock muffler. If you have a high throughput cat-back exhaust system, you can get a high-flow cat anyway. You might want to think about that, though, 'cuz it's going to be really expensive, and your power and torque gains are going to be in the mid to low single digit percentages unless you've got a whole lot more going on in your engine, despite what fancy "tuner" car people will tell you to justify ludicrous expenditures.
2. Is there really a car made since like 1970 that uses air injection to the cat? Certainly not one with electronic fuel injection... I have a thing for old German cars, granted, so I may have biased experience, but I have *never* actually seen one. It is my understanding that certainly in a modern engine, you'll never see one. Even if there is one somewhere, the alternator resistance to drive a small electric air pump would be what... a tenth of a horse?
Bottom line, unless you're driving incredibly short distances frequently, the emissions system pays for itself in mileage. Your injection system is, indeed, wasting fuel until it's at operating temperature. After that, part of a modern emission system is keeping mileage down and storing oxygen from the exhaust stream after a rich fuel/air mix from acceleration.
Thus: in city driving, there will be no loss at all. If you're on the freeway (and not passing anyone) for a really long time, the EFI may waste a little fuel just to keep oxygen in the cat, but
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?
Probably the two most advanced "affordable" EV/PHEV projects right now are the Aptera (both the $27k Typ-1e and $30k Typ-1h) and the $25k Mitsubishi MiEV. You could probably get either by late next year, although you'll need to be tricky about it if you want it that soon (I'm getting my Aptera through a California intermediary). The Subaru R1e, also coming out in the same timeframe, doesn't cut it on range. The GM Volt will be $30-40k, with a late 2010/early 2011 timeframe. Another one to keep an eye on is the $25k VentureOne. If you don't mind tandem seating, it looks like a very fun ride. You may also want to watch Nissan-Renault and Think's offerings, and watch to see if Subaru decides to commercialize the G4e. All of these vehicles should be expected to be using long-life LiP batteries (10+ years with minimal degradation typical), with the exception of the G4e, which uses next generation, double energy density lithium vanadium oxide batteries (don't have info on their reliability yet)
:) ) for the electric-only version (not sure about the PHEV), energy efficient due to low cross-sectional area, and drives like a motorcycle -- the car automatically tilts into turns ("flying the road"). 0-60 in 7 seconds.
More detailed info on four of the less expensive models:
* Aptera: Space-age styling, lots of neat interior and safety features, 2 1/2 seater, extreme energy efficiency (~80Wh/mi; ~200 is typical for EVs). Efficient use of electricity means a smaller (and thus cheaper to replace) battery pack and faster charging on less power. Typ-1e gets 120 miles electric range while the Typ-1h goes 40 miles electric then gets 130mpg. 0-60 in 10 seconds.
* MiEV: More conventional styling, mainstream manufacturer, 4 seater, 120 mile range, lots of charging options. 0-60 in ~10 seconds (heard some conflicting info, but that should be approximately right).
* Volt: "Chopped" styling, mainstream manufacturer, 4 seater, 40 mile electric range PHEV, 50mpg after that. 0-60 in 8.5 seconds.
* VentureOne: Thin tandem two seater, 120 mile range (noticing a trend?
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
Yeah -- we're all taller than you.
Here's a photo of the winning car (the one on the right, #22), where are these 200 sq ft of solar panels you're talking about? There's also a better angle on the team's homepage here, no solar panels to be seen. Heck, that car doesn't even have 200 sq feet of surface area even if you counted the belly.
Did you know that while solar cars did compete, they were not allowed to win the grand prize?
Yeah, you're full of it. But at least you tricked a mod or two.
The enemies of Democracy are
It's just like software bloat. Car models get bigger over time. A new Honda Fit is a closer match to your 92 Civic. It's probably a little smaller outside, but it matches the old Civic for power, comfort and interior room.
BTW, the EPA adjusted the mileage test for 2008. MPG is down across the board because the old mileage test was unrealistic and didn't match up with real world (read lead-footed) driving.
http://www.fueleconomy.gov/feg/ratings2008.shtml
Honda Fit got 38 mpg highway under the old test, 34 mpg highway under the new test. If you drive it like a granny, you'd still get 38 mpg.
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)
Actually, I just looked under my 1996 Oldsmobile Ciera recently and was suprised to see that there is indeed a stainless steel air injection line running into the catalytic converter - at least I'm pretty sure that's what it does, what else could it be?
The back pressure is largely additive: its in addition to the muffler and resonator. EFI does not choke the engine like a carb; it always runs at optimum fuel mix. It just might be more fuel and less air when the engine is cold. It doesn't really "waste" it. Also, the emissions system cannot ADD to gas mileage, so it cannot pay for itself in terms of it. If you take it out, the computer will simply correct the fuel mileage.
My car, when it was new, got 38MPG(actual reading on a trip to Ohio) on the highway and generated 155Hp. You'd be VERY hard pressed to find such mileage results today.
Anyway, YES, EFI cars have far less emission control systems than older carbed cars. Less PCV and vacuum equipment, smaller or nonexistant air pumps - but the catalytic converter will always be there. The reason is that most of the the converter takes care of is not a part of the combustion of fuel- but is rather the result of what happens to the rest of the air (nitrogen and such) in the extreme heat and such. Efficiency cannot affect that - in fact, higher operating temperatures of modern cars have made it worse.
Nitrous oxides, for instance. There's no nitrogen in gasoline.
Where I live, more than half the cost of electric is in the delivery/line charge.
:)
It doesn't matter how much is in the "delivery line charge"; cost does not equal efficiency. In the US, the average transmission efficiency is 92.8%.
you lose 15% in the charger
AC Propulsion's 20kW charger is 93% efficient, while their 150kW charger is 90% efficient. That's pretty typical for non-inductive chargers.
and another 30% to the lead acid battery.
Lead-acid battery? Lol, what do you think we're talking about here, golf carts? NEVs? Even Firefly lead acid batteries are simply unsuitable for these sort of tasks. Way too short lifespan, way to inefficient, way too low energy density. We're talking about lithium ion variants. Lithium ion batteries are over 99% efficient (that's why they charge and discharge cool).
So while at the power plant rock in efficiency, it doubles in cost getting to my house
Please learn to separate the concepts of "cost" and "efficiency".
My understanding is Gas engine are 70-80% efficient
Try about 20%, give or take.
It's okay to be unfamiliar with this topic. Just educate yourself so you're more informed for future debates and we can talk some more.
I'll BUILD someone to replace you. Some kind of gamma-powered monster, with a heart as black as coal!
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?