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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."
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!
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
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
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.
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
How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
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"
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
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.