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Hybrid Drivers Provide Real-World Mileage Data
The hot-selling Toyota Prius averages 48 miles per gallon among over 150 cars from across the country, with most drivers achieving between 45 and 51. The V-6 Honda Accord Hybrid delivers 30 miles per gallon while Ford's Escape Hybrid SUV averages 28. All hybrid owners are encouraged to post their data for these and other cars on the Internet's largest hybrid mileage database.
Reliable fuel economy figures are increasingly important as consumers explore their options in an emerging hybrid car market. Hybrids, like the new Lexus RX 400h, pair combustion engines with electric motors that recharge while driving to improve gas efficiency. "Until lately," said GreenHybrid creator Jason Siegel, "consumers have associated hybrid vehicles with a small niche of fuel-conscious environmentalists, but today's hybrids offer the best combination of high performance, great mileage and luxury features of any cars on the market."
I guess they didn't have enough charge in their electric batteries... Wait for it, once their done braking there should be a little bit left! Oh wait, they didn't fill up on gas because prices are so high... oh well.
nyudlink: here.
Before anyone gets confused, I just want to point out that the Accord hybrid is not supposed to be super-efficient like the Prius. It's the top-of-the-line Accord, and the hybrid power is mostly used to increase performance while retaining similar fuel economy to the slower models. It's quite zippy; IIRC it has better 0-60 times than a V6 Mustang.
It's hard to be religious when certain people are never incinerated by bolts of lightning.
Turbo-Diesel owners have been seeing numbers in this range, or better, for years.
Seems what the market needs is a diesel/electric hybrid to get numbers that will impress any diesel owners.
Otherwise most TDI Volkswagens have been able to outshine these numbers for years. Plus you can't run a Prius on used cooking oil.
Which is exactly why the speed limit when from 70 to 55 durring the oil crisis. Someone will correct me, but wind resistance is cubed every time you double your speed. Our old '84 caddilac with trip computer got 25mpg at 64mph, but got 17-19mpg at 70mph. Closer to 28mpg at 55mph.
moox. for a new generation.
There are many dealerships that do not add a markup. If the one near you does, just say "Sorry, but I refuse to pay your luxury tax. You have lost any future business from me." and go somewhere else.
Call all the Toyota dealers near you, even 200-300 miles away, I can almost guarantee that you'll find one in stock, at MSRP. (I only had to wait 2 days for mine. And it wasn't even 'ordering', it was calling all the dealers on Saturday, getting on their 'lists', and getting a call back on Monday saying they had 2 in stock that met my requirements (Blue, Tan, or Green, 2004 Packages 7 or 9, which are now called 5 and 6.) I drove a Blue package 7 Prius off the lot a mere 2 days after starting my search. (I could have had a top-of-the-line package 9, but it was in 'Tideland Pearl', which I mistakenly thought was green, it's more of an olive drab. So I picked the lesser-package 7 in blue, because I actually liked that color, and the extra features weren't important enough for me to want to wait.)
Another non-functioning site was "uncertainty.microsoft.com."
The purpose of that site was not known.
Really sorry, guys. Slashdot sent me so many referrals the whole server went down! I won't be able to get ahold of my host for 2 hours, so please sit tight. Very sorry.
Jason Siegel
GreenHybrid.com
I know I get much worse mileage driving at 80-90 than I do at 60-70.
:-P
That's because most transmissions in production cars have their highest geared tuned so that the engine's in its RPM sweet-spot around 60-70mph; after that, the amount of gas per RPM starts to increase considerably more.
I'm curious as to just how high the grandparent kept his RPMs when he got similiar gas mileage driving timidly and agressively. Also, where has anyone heard stopping slowly increases mileage? Maybe in a car with regenerative breaking, but certainly not in a good ol' ICE powered car. If your foot's not on the gas, only idle gas is going to the engine (unless the computer is doing something, but it shouldn't affect that much). Unless I'm missing something, I can't see how slowing down gradually will increase anything beside the frustration of the driver behind you because you're not getting to a stop light quicker
We now have confirmed reports from an informed Orange County minister that Ethel is still an active communist.
I get 42mpg in my daily drive, but not batteries to keep charged!
Below 55, your gas mileage gets better the faster you go. After 55 it starts to drop off. There's a neat graph here.
You probably implied why, but just to make sure, let's state why: The air drag your car feels is proportional to the square of speed. Stick your palm out the window to test. At 1 mph almost none of the gas is spent on fighting air, because the air has time to get behind you. At such speed your gas goes to fight friction in the tires bending and relaxing, and the pistons, cylinders, gears rubbing up against each other inside the engine. But at 90 mph a very significant portion is spent on air drag friction on top of the tire and internal engine friction. The actual formula is
F=1/2 * A * Cd * r * V^2
where
F - is the force pulling your car or your palm back
A - cross sectional area of your palm or car
Cd - is the drag coefficient dependent on shape of your car or palm - i.e. do you look like a parachute or a bullet to the incoming wind, because even if you have the same square footage area facing the wind, its shape matters
r - air density, dependent on temperature, humidity, barometric pressure/altitude
V^2 - your velocity squared
Using air conditioning is supposed to make a difference, but last autumn I drove the same route for a week and noticed that my MPG was higher during a week where I was using air conditioning compared to one where I only had the windows open or the fan on.
You may also want to check out How Stuff Works's site.
I haven't noticed any significant deviation in my gas mileage depending on how I drive. The two things that seem to make a difference are a) highway speeds and b) type of roads travelled on. Back when I drove mainly to school 3 miles away (with stops approx. 1/4 - 1 mi between eachother), I got 16-17mpg, but now that I drive to work 8 miles away (on streches of road mainly with 1-3 mi between stops), I get 19-20mpg. Driving agressively (not to the point where I floor it usually, but close) makes no apparent difference.
I drive a 1989 Chevrolet Cavalier with a V6 engine.
Major Sucker Retail Price. Sorry for the shameless plug, but I found the tips at carbuyingtips.com helpful.
And I drove my Civic Hybrid from the dealer with the dealer getting a fair 5% profit.
--You will rephrase your request for me to go to hell. Goto statements are not acceptable programming constructs
wind resistance is cubed every time you double your speed.
;-)
Squared.
Someone will correct me
Glad to help.
The only reason stopping slowly helps MPG is actually similar to the concept of regenerative braking, albiet vaguely.
When you stop abruptly, you will arrive at the stoplight more quickly (higher speed for longer) therefore there is a greater probability of it still being red when you arrive at it, therefore you are more likely to be at ~0MPH, thus requiring to accelerate your car from 0 to whatever your cruising speed is (hence more energy and fule needed.)
If you ease off the accellerator when you first see the red light, you are a) not burning as much gas on your approach to the light, b) less likely to come to a full stop, and thus will have a smaller overall change in speed, less power required to return to cruising speed, less gas used. On the flip side, with this technique your chance of slowing down at a light is near 100% whereas in zero traffic, the abrupt stop method does give you a chance of zero change in speed, but you can only rely on that if you know the light timing and there's no traffic ahead to make you slow down anyway.
Incidentally, when I slow down earlier, and roll up to the red light at 20mph, still at speed when it turns, vs hitting it at 45 a few seconds sooner and needing to stop all the way, I find by a block past the light I've passed virtually everyone who was stopped at it, and so in addition to being energy efficient I've increased my average speed too.
Make sense?
Re: last line of parent: There is no benefit, as described above, to "getting to a stop light quicker" if it is red; hence the driver behind you has no real reason to be annoyed. But yeah, I'm sure he will be. Ignorance here is less than bliss.
Please see http://www.planettran.com/press/NYT-05022004.htm which talks about Andrew Grant, the taxi driver. He noted that reliability was actually higher in the Prius and credits this due to the fact that the engine doesn't idle, and regenerative braking limits wear on the mechanical brakes. Apparently, he's on his third Prius now.
Of course, this is a special case since a taxi would get atypical usage.
You're on the right track, but you also need to remember that when velocity is doubled, aerodynamic drag is quadrupled. At steady highway speeds, other sources of drag are almost negligible.
You mean other sources of loss, not drag. And that's not true - aerodynamic losses start taking over at highway speeds, but other sources are certainly not negligible.
And anyway, fuel efficiency for an engine can drop very rapidly when you fall out of the power band. Doesn't matter if you reduce your aerodynamic drag by 40% (probably reducing your total overall losses by 20-30%) if your engine efficiency drops by 50% as well.
Well, at the risk of sounding like a Toyota ad, the Prius is built using 90% recyclable materials. For the soundproofing, they literally use shredded material from old cars. They use a tenth of the lead and a tenth of the PVC they were using in their cars in 1996. They even use plant-derived bioplastic for the floor mats.
http://www.toyota.co.jp/en/news/03/0901a.html
GCHQ Quantum Insert installed. If only our tongues were made of glass, how much more careful we would be when we speak
For an engineer's analysis:
"The Bottomless Well:
The Twilight of Fuel, the Virtue of Waste, and Why We Will Never Run Out of Energy"
by Peter W. Huber,Mark P. Mills.
Available at all the usual book outlets.
I didn't desert Windows; Windows deserted me: BSOD
How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
As I own one, and live in California.
Cali DMV:
" Currently, smog inspections are required for all vehicles except diesel powered vehicles, electric, natural gas powered vehicles over 14,000 lbs, hybrids, motorcycles, trailers, or vehicles 1975 and older. "
I bought my vehicle out of state and took it in to Cali, so I don't know about any of the new purchase requirements... but it's been registered in CA for a few years with no problems.
Mike
At highway speeds, running the air conditioner is almost always going to be more fuel efficient than putting the windows down.
At slower speeds where wind resistance doesn't really come into play. cruising down residential streets at 25 MPH or stuck in stop-n-go traffic, the AC will burn more fuel than having your windows down.
Adjust your cooling accordingly.
One of the things I learned when dealing with wind turbines is that double the wind-speed roughly equals eight times the power. Order n cubed. This doesn't work at very high or very low wind speeds because of turbulence and cavitation and similar effects, and goes completely wonky again near the speed of sound in the medium, but for highway-type speeds it's bang on. It may also be different for (mostly) non-rotating cars, but it is indeed worse than n squared once you get above about 50km/h.
Got time? Spend some of it coding or testing
That's the force, but the thing you really want to know if you're talking about mileage is the power (energy per unit time), which goes as V^3.
Since aluminum manufacturing consumes a notoriously large amount of energy, let's assume cars are made of 100% aluminum.
The energy required to produce aluminum is about 15 KWh/Kg.
Assuming the average car weighs 2 tons, that's 1814 Kg of aluminum.
1814 Kg * 15 KWh/Kg comes out to 27,210 KWh. At 5 cents per KWh (industrial prices), that's $1500 worth of energy to smelt our aluminum. As far as materials costs go, that sounds about right.
Fine, now a gallon of gasoline contains 125,000 Btu of energy. That's about 37 KWh.
If your car's getting 40 mpg, and if you're driving it 10,000 miles per year, you're using 250 gallons of gasoline a year. 250 * 37 KWh is 9,250 KWh per year.
Drive your car for three years and you've used more energy than it took to build. If we wanted to compare the "theoretical maximum" amount of energy that can be extracted (at 50% efficiency) from gasoline, you're only looking at a year and a half. Any car built in the last ten years should last five to ten times that long.
"I assumed blithely that there were no elves out there in the darkness"
Are you that ignorant?
BP Ultimate fuel questions
Q. Why five tankfuls to clean up a dirty engine?
A. With increased detergency, Amoco Ultimate from BP will clean up engines with deposits in about 1,500 miles of use at an average of 300 miles per tank. Those five tankfuls will restore the engine to its previous level of performance, and with continuous use, Amoco Ultimate will keep that engine running cleanly.
Q. Why don't you apply the increased detergent additive in all three grades?
A. We offer customers a choice. Many customers have told us they want the enhanced performance that is possible in a premium gasoline.
Castrol Motor Oil basics
Additives
Base oil alone is not enough to properly protect your engine. Motor oil needs to perform a wide variety of functions under a wide range of engine operating conditions. Therefore several additives are incorporated into the formulation:
Detergent/dispersant additives - used to maintain engine cleanliness, keeping the various contaminants in a fine suspension and preventing them from settling out on vital engine components.
If I point out that you are incorrect, making me a foe does not make you any more correct.
I am referring to American gallons in my numbers-
-sirket
You should review your freshman physics, in particular, kenetic energy; E=½mv×v. While no car is ideal, there is no fundamental reason that a car should be less efficient at lower power levels. At any RPM, there should be an optimally-efficient power output, so anything other than that will produce sub-optimal efficiency.
Of course, if you are driving on the freeway all the time, all of your fuel use will go to fighting resistance and changing altitude.
Finally, in a world of ideal engines but with friction, the faster you accelerate the less energy it takes to get up to speed; if you accelerate instantly, you are 100% efficient at getting up to speed; if you accelerate slowly, you expend that same energy to get up to speed, but you also expend energy to overcome friction over the distance you traveled.
Sorry, not any car. Being in a hybrid article I feel no problem posting this: at least for low speeds, you're dead wrong. I can accelerate aggressively from the light, and reach 40 mph, let go of the gas, and drive on battery for the rest of the 16 seconds, meanwhile if I accelerate slowly up to 40, assuming the gas engine is on during acceleration, I'll end up using more gas.
My assumption, which you may not be making, is that you're also factoring in the fact that you can be operating at idle/no engine for the remainder of whatever time you'd otherwise be accelerating. If you take in to account ONLY the time it takes to get to your target speed, then perhaps you are right. If you take the slowest you can accelerate up to a given speed X, and then take the fastest and then coast for the remainder of the time, you are 1) much closer to your eventual destination, costing less time.. and if your engine is on at that speed, then less time with an idling engine, and 2) not putting stress on the engine for as long of time. Acceleration is where horsepower is needed, not coasting. Minimize the time that the engine is needing serious usage.
I welcome your challenge to these claims.
Excellent point. I have a Honda Jazz GLi (in Japan, it is called the "Fit") and on a recent trip to the NSW south coast from Canberra, I got 4.2 L/100km down there and a total trip usage of 4.6 L/100km. By accelerating and slowing down slowly, I was able to cut my previous trip usage by a full litre per 100 km.
The Jazz has a 1.3 L dual spark ignition motor coupled with a CVT (Continuously Variable Transmission). It costs about 1/2 to 2/3 of a Prius. It doesn't seem to be available in in the US. Here is more info http://www.honda.com.au/jazz/gli/index.htm
PS Google tells me that 4.2 L/100km = 56 mpg.
Slashdot: Where nerds gather to pool their ignorance
Dunno about his sources, but I get 2 million *possible* drivers. Before anyone attacks that number, note it comes from an immigrant activist site
Another state says there are one million driving currently.
There were 24.1 million licensed drivers in 2003. So that makes illegals at most 8.3% of the drivers in California.
That's quite significant.
I tried every decent and legal way I could think of to resolve the issue w/the business before I rented the chicken suit
I'm glad to notice you are considering wind resistance as well as the difference in stopm and go trafic verses continuous highway driving. The bigest factor in speed verses fuel usage would be resistance.
.5 to 1 mpg more fuels econemy then without using it. One mpg doesn't seem like much but it adds up. Especialy if you are getting lower mpg.
Wind resistance, starting to move resistance, going up hills resistance, and the difference the weight has on thse resistance play a crucial role in gas miliage. I have a van and with it fully loaded with camping and hunting gear i average around 1 or 2 miles per gallong less. A slight breeze will drop my miliage another 1 or so miles per gallon on the same 200 mile trip. If it is realy windy, i can expect a little more drop. Newer stream lined cars wouldn't see as dramitc effect as i do on the wind but might see more of an effect on the weight because thier engines typicaly are smaller. Going up some hills, I tend to pull away from other trafic even when pulling a boat or 4 wheelers. I can also get better miliage in town when my tanks are half full (less then 20 gallons compared to 45 gallons total full) with the same cargo. My overdrive in town causes me to use more gass too. I think it is because the high gearing requires more fuel to maintain the same power ratio to the ground.
On the same note, While in fith gear, if you are having to depress the excelorator more to maintain your speed then you would in fourth gear, you might actualy use more gass then if you increased the RPMS and ran at a lower gearing.
When i drove a class 8 tractor trailor the manufacturers of the engines (detroit deisel) gave us training on fuel econemy. Some basic bullet points were that the engines have a peak power to torque ratio were when the rpm making the most power croses the rpms making the most torque resulted in the best fuel econemy. The transmisions and rearends were geared with this in mind alng with the rated top speed. Granted with a deisel engine the RPMs were alot lower and basicaly limited to around 2200 - 2300. We usualy shifted and attempted to keep them around 1700-1800 rpms.
Without idle time (as you mentioned earlier) I could average about 8-9 miles per gallon running at gross (79-80,000 lb). This was up from 4.5 to 5 miles per gallon before we had our little talk. That was acording to the little engine computer read out on the dash. Durring real windy times i actualy get better miliage at slower speed but could run 70 - 80 mph most the time were the speed limit allwed. On a calm day the lower speed would be less then 1 half a mile per gallon because of the gearing. If you could place your car on a dino and check the torque and power rats, you might find an ideal range to drive long trips and realize a big fuel savings.
Another point was the electronic cruise control. Running with the cruise control allowed engines computer to caculate the exact amount of fuel needed to maintain speed were driving by foot would cause speed to fluctuate enough that the driver would over compensate the throttle and apply too much power to maintain speed. My buick's cruise control saves fuel on long trips much the same but my van's cruise is too old to have much difference (rebuilt and pumped '84 chevy 350). My semi truck would see around
From http://john1701a.com/ (lots of Prius info!):
SMOG, which consists of NOx (Nitrogen Oxides) and HC (Hydrocarbons) plus a little bit of CO (Carbon Monoxide), is the type of vehicle emission that is harder to quantify, since MPG makes no difference. This pollution contributes to that nasty orange haze floating above most all of the major metro areas throughout the United States, which leads to breathing complications for young children and the elderly.
The "SULEV" emission rating was created to identify vehicles that were specially designed to reduce SMOG related emissions. The classic Prius achieves that criteria. The 2004 Prius actually exceeds it (having earned the "AT-PZEV" rating). Some traditional vehicles actually are SULEV too, believe it or not; but unfortunately they are only available in California and their MPG is very disappointing (even lower than their polluting counterpart). Lastly, not to put down the other hybrids, but... not every type offers SULEV cleanness; some are only ULEV, which is 72% dirtier with respect to SMOG related emissions. So don't just assume the highest efficiency equates to the lowest emissions.
The Prius is designed to run the engine at a point where it produces the least pollution, which is not always the best mileage. Sometimes, the engine will produce more power than is needed with the excess charging the batteries.
Actually, modern EFI engines turn off the injectors when at zero throttle opening above some RPM level.
My car, turns off the injectors when coasting until engine speed drops to 1500RPM - theres a very faint-but-detectable jolt when they are turned back on. This doesn't hurt your engine because there's no fuel to burn at all compared to a lean mix.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
"There is a limit as to how fast you can safely travel which is mainly governed by how quickly you can stop. Sport Compact Car magazine recently reviewed a race-ready Mitsubishi Evolution 8 with upgraded everything including a beefed up braking system."
But I have to share the road with big trucks, sports cars, SUVs, School Busses, hybrids, etc. The road has a mix of brand new cars to cars that are 30 or 40 years old along with busses and trucks. Drivers vary from people who are about to die of old age who are missing spots in their vision to people who just got their permit, to 25 year old frat party animals to soccer moms, professional drivers (of all types), etc.
How fast I can stop is a factor including my reflexes, vehicle, tires, road conditions, weight in tow, etc. Put 10 cars behind each other, and one or two guys with too much testosterone weaving through, and although it might be safe for the guys with the muscle car, the fast reflexes, and the adrenaline, it's the guy who slams on the brakes and gets hit by the Mac truck behind him that's going to be paralyzed from the waist down.
There are so many factors to take into account, but it's not rocket science. Crashes happen because people make bad choices without understanding or caring about the consequences. They know those choices are wrong. Rarely are the choices that cause crashes and death are the ones made by the road engineers or car engineers. Equipment failure shouldn't always be the cause of death... These things are designed with room to spare on safety, but people gobble up those design constraints through bad choices.
Wow, 40% heavier and still gets the same mileage! Any other person would say this was a major improvement.
AND, the Prius is a 5 passenger car with AT-PZEV emissions. One lawn mower session puts out more emissions than a Prius after driving 500 miles. Think about the summation of health costs saved with cleaner air, besides just oil.
And take a look at this picture of your 31.4 cu.ft space Metro. I don't see a huge cargo space behind the back seats, so it must come from folding down the seats.
If you get to do that, you get to do that with the Prius too, which means > 16.1 cu ft of space. Probably closer to 54, if you added 16.1 + rear legroom plus some hand waving.
Your specs say the Metro is a 151 x 62.7 x 53.5 = roughly ~506521.95 cu.in compared to the Prius's 175 x 67.9 x 58.1 = roughly ~690373 cu.in.
Although I see your point about 15 years of innovation and we not CLOSER to 100MPG!
Anyways, so dunno what you're talking about how the Metro is better. QED.
Virtually every accident I have witnessed that was clear caused serious property damange, injury and death (seen a few of those, unfortunately)... nearly 100% of those, if not 100% were people trying to swerve around slower or stopped traffic.
Why is that? People in the US are not taught how to control a car, they are only taught how to interact with other cars on the road. Watch someone who is a professional or amateur race driver (who understands vehicle dynamics at the limit) in those situations -- they react totally differently. Threshold brake, keep the ABS from engaging, and stay in a straight line. If you can't scrub the speed to the point where the impact will be a non-event (5mph), you were following WAY WAY too closely. Better to hit the car softly than risk oversteering into it, or worse understeering off the road or into another traffic lane. Once a car starts to lose traction, it takes a very skilled driver to make it go where they want it to.
If you don't know the reasons going 100mph is unsafe for most drivers no matter what the road conditions, you're not in the "knowledgable driver" camp. 100mph is dangerous in any situation in 99% of the cars on the road. Its not how the car and driver can handle expected situations, its how that car and driver can handle an unexpected one. In virtually every case, at 100mph they can't.
Two speed limits isn't the answer. Requiring something more than ten hours of on the road driving and 30 hours of classroom time is the answer. Require limited traction training the way many european countries do. Or maybe just even mention the concept of a traction cirle to young drivers and explain why their lives may depend on them understanding it. A properly trained driver can be in just as much control of a car with four wheel sliding as a badly trained driver on dry pavement.
I have to point out that AT WORST my mileage on a '98 Jetta TDI (read: diesel) has been 46 mpg.
/. noted that the VW TDI's were getting >= miles per gallon than the hybrids. So, this post is just me giving back.
The average is a steady 48 mpg.
I was an avid follower of hybrids until an article on
Before I part with'em: two pennies weigh ~4.996+/-0.014g, have a zinc core, and the face of Lincoln. You can keep 'em.
Wrong. Please get a grip on basic physics.
Indeed.
Going back to the person who said that damage increases linearly with speed... What? A car going 55 MPH is moving at the same speed as a car dropped from 101 feet. A car going 75 MPH, or 36% faster, hits with the same speed as a car dropped from 188 feet! Now maybe you have a different idea of what kind of damage can result in free-fall, but basically, when falling, damage caused on impact with a stationary object (the ground) increases linearly with height .
From this, we can see that going 36% faster increases the damage on impact by 87%!