TouchDown
Is it Friday yet?
It's a serious consipracy against all who are Redneck. Where's the GD T-Tops anyway?
Why does it take a hybrid to get 45 mpg these days
- Thread starter JoeysVee
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rdbse
Research Fellow
Actually, that is a great idea. We would see a revolution in hybrid technology.
TouchDown
Is it Friday yet?
Al Gore's son was pulled over going 100+ in a hybrid... you might be onto something...
msnbc article
Even better - what if they were powered by hydrogen fuel cells, and when there was a wreck, the cars would explode??? Kinda like NASCAR mixed with a little Mad Max beyond Thunderdome.
msnbc article
Even better - what if they were powered by hydrogen fuel cells, and when there was a wreck, the cars would explode??? Kinda like NASCAR mixed with a little Mad Max beyond Thunderdome.
G
grover
http://www.autoweek.com/apps/pbcs.dll/arti.../THISWEEKSISSUE
Also, looks like ethis might be his website, but it's not working for me: http://www.sixstroke.com/
I have a hard time picturing this going 200,000 miles, too. The "catch" is that you have to fill up with equal parts water and gas at each fill-up, which largely negates the bonus of not needing a radiator. I don't see that metellurgy couldn't produce a corrosion-resistant combustion chamber that could stand up to the steam. Piston rings capable of sealing against exhaust gasses should seal against steam, too. Heat expansion might be an issue; that many heat/cool cycles has to wreak havoc with fatigue.
G
grover
hahaha... can you imagine the fans arguing over whether Toyota or Honda built a better NASCAR?SapperPE said:
Would the complete elimination of pit-stops make a 500 mile race less fun to watch, though?
J
JohnNevets
Isn't IRL or Cart running on 100% ethanol or something like that. Granted they were already running on another type of alcohol before (I believe Methanol), but it shows it could be done.
I never popped into this forum since I'm not an ME, but I'm glad I found this very interesting thread. Since I've lived near Detroit all my life it's hard not to keep up on what's going on in the auto industry. Forgive me if I'm repeating a lot of what's already being said, but I'd like to get my 2 cents in.
I personally think the auto industry has done a good job of "increasing" fuel mileage over the years, given everything else that's happened. I'll get back to this point later, but first I have a few other points to make.
1. Many of the vehicles that made great fuel mileage in the past were diesels. For many reasons diesels have been on the sidelines for U.S. passenger cars for quite a while. One is the unappealing sound and smell of the old diesels. Another is pollution concerns--sulfur emmissions (a contributor to acid rain) and particulate matter. A lot of advancement has been made on diesel technology, and they are all the rage in Europe, but they haven't made it over here yet. From what I've read, a big reason for that is the EPA still doesn't like the pollution. I guess they've come up with some super-duper catalytic converters for the sulfur but the PM is still a problem. I've heard of using an exhaust filter to get rid of the particulate, but the EPA doesn't like this because it the filter would eventually clog up and it would be too easy for the consumer to just remove the filter rather than clean/replace it. But given the potential here, I think we'll eventually see a comeback of diesels in the U.S.
2. Power. The horsepower in American vehicles has risen significantly in the past couple decades--not because Detroit is forcing it on us, but because that's what consumers are demanding. My daily driver is a 2006 Chevy Aveo that makes a whopping 100 hp, and someone usually wants to run me over coming off a traffic light. I see this as a pointless waste of energy. Don't get me wrong--I like to go fast too (I have a motorcycle for this specific purpose), but do you really have to do it at every single stoplight? Anyway, my point is that VW Rabbit probably made very little horsepower, which would be unacceptable to the average American consumer these days, when it seems the average vehicle is well over 200 hp.
3. Speed. People are driving a lot faster than they used to. Again, I'm not an ME and I don't remember the exact relationship between speed and drag but I thought drag was proportional to the square of speed--which means speed has a big effect on fuel economy. Remember that the national speed limit was reduced to 55 mph by Nixon to increase fuel economy. Again, I think this would be unacceptable to the average American these days. Back in the 80's, most cars were designed to be most efficient at 55 mph. A case in point: in the early 90's, a friend used to drive around in his mom's Pontiac 6000, and I swear that car wouldn't go more than 75 mph; conversely, my Aveo is perfectly happy at 80 mph. How fast could that VW Rabbit go?
4. Weight. As has already been said here, cars are heavier than they used to be for a number of reasons. I think some of it may be due to structural safety improvements, but there are also all the gadgets like power windows and locks, ABS, air bags, DVD systems and maybe even A/C that the 80's cars didn't have. My welter-weight Aveo weighs in at just under 2000 pounds, and I'll bet that Rabbit is much lighter. (Note that the Aveo has a steel block).
Taking all of this into account, I'll bet if you took 80's technology and tried to build a car with the same performance and weight of the average sedan of today, it would get much lower fuel economy. But still there's obviously a lot more that can be done, especially with diesels and ligher-weight advanced materials, but that will take more R&D (time and money). The fastest way to increase fuel economy would be to break our addiction to speed and power. I've found one way to do this but it's not the most practical thing--I mainly drive the Aveo, but I've got the motorcycle when I feel the need for speed, and I have a 1996 Ford Bronco when I have the need for big or 4wd.
Finally, I'll be curious to see how the UAW contracts work out over the next few months, but that's a whole other story.
I personally think the auto industry has done a good job of "increasing" fuel mileage over the years, given everything else that's happened. I'll get back to this point later, but first I have a few other points to make.
1. Many of the vehicles that made great fuel mileage in the past were diesels. For many reasons diesels have been on the sidelines for U.S. passenger cars for quite a while. One is the unappealing sound and smell of the old diesels. Another is pollution concerns--sulfur emmissions (a contributor to acid rain) and particulate matter. A lot of advancement has been made on diesel technology, and they are all the rage in Europe, but they haven't made it over here yet. From what I've read, a big reason for that is the EPA still doesn't like the pollution. I guess they've come up with some super-duper catalytic converters for the sulfur but the PM is still a problem. I've heard of using an exhaust filter to get rid of the particulate, but the EPA doesn't like this because it the filter would eventually clog up and it would be too easy for the consumer to just remove the filter rather than clean/replace it. But given the potential here, I think we'll eventually see a comeback of diesels in the U.S.
2. Power. The horsepower in American vehicles has risen significantly in the past couple decades--not because Detroit is forcing it on us, but because that's what consumers are demanding. My daily driver is a 2006 Chevy Aveo that makes a whopping 100 hp, and someone usually wants to run me over coming off a traffic light. I see this as a pointless waste of energy. Don't get me wrong--I like to go fast too (I have a motorcycle for this specific purpose), but do you really have to do it at every single stoplight? Anyway, my point is that VW Rabbit probably made very little horsepower, which would be unacceptable to the average American consumer these days, when it seems the average vehicle is well over 200 hp.
3. Speed. People are driving a lot faster than they used to. Again, I'm not an ME and I don't remember the exact relationship between speed and drag but I thought drag was proportional to the square of speed--which means speed has a big effect on fuel economy. Remember that the national speed limit was reduced to 55 mph by Nixon to increase fuel economy. Again, I think this would be unacceptable to the average American these days. Back in the 80's, most cars were designed to be most efficient at 55 mph. A case in point: in the early 90's, a friend used to drive around in his mom's Pontiac 6000, and I swear that car wouldn't go more than 75 mph; conversely, my Aveo is perfectly happy at 80 mph. How fast could that VW Rabbit go?
4. Weight. As has already been said here, cars are heavier than they used to be for a number of reasons. I think some of it may be due to structural safety improvements, but there are also all the gadgets like power windows and locks, ABS, air bags, DVD systems and maybe even A/C that the 80's cars didn't have. My welter-weight Aveo weighs in at just under 2000 pounds, and I'll bet that Rabbit is much lighter. (Note that the Aveo has a steel block).
Taking all of this into account, I'll bet if you took 80's technology and tried to build a car with the same performance and weight of the average sedan of today, it would get much lower fuel economy. But still there's obviously a lot more that can be done, especially with diesels and ligher-weight advanced materials, but that will take more R&D (time and money). The fastest way to increase fuel economy would be to break our addiction to speed and power. I've found one way to do this but it's not the most practical thing--I mainly drive the Aveo, but I've got the motorcycle when I feel the need for speed, and I have a 1996 Ford Bronco when I have the need for big or 4wd.
Finally, I'll be curious to see how the UAW contracts work out over the next few months, but that's a whole other story.
TouchDown
Is it Friday yet?
I wish Ford would take their Escape Hybrid platform and develop a truck out of it that gets 35MPG, with the feel of a V6 under the hood.
It would compete with the Tacoma, Colorado, and Frontier and get 2x+ gas mileage.
Does anyone know of a hybrid truck that will get in the 30's in MPG? I've seen the Chevy Silverado get's a boost of about 5MPG from 13 to 18MPG on it's hybrid.
It would compete with the Tacoma, Colorado, and Frontier and get 2x+ gas mileage.
Does anyone know of a hybrid truck that will get in the 30's in MPG? I've seen the Chevy Silverado get's a boost of about 5MPG from 13 to 18MPG on it's hybrid.
Nothing personal, but I think it's high time to give up on all vehicles that get less than 40-50 mpg. There is simply no stopping the rising demand of oil, now that China's growth has gone beyond critical mass. Demand from China is predicted to more than double in the next 5-10 years, so you can expect oil prices to be high from now on. And sooner or later, supply will begin dropping. Perhaps sooner than later - when I worked in the oil field in the early 1990s, the industry was predicting supply to begin declining in 20-25 years (2015-ish). I think this date has been pushed back now with a handful of new discoveries and better (more expensive) extraction technologies, but demand has increased significantly as well. It's a finite resource and no one (in the know) has ever denied that we will eventually run out of it.
At any rate, I think it's time to give up on the over-sized SUVs and trucks, unless something other than oil is powering them.
At any rate, I think it's time to give up on the over-sized SUVs and trucks, unless something other than oil is powering them.
Road Guy
Well-known member
If we all bought a hybrid tomorrow, we would see the same rise in gas prices due to folks buying less gas and the oil folks wanting to keep their gold plated yachts, would just charge more. This is overly cynical but I really think there will be some sort of email to the President when we get to within 5-7 years of oil supply left and then some alternative mode will be created, Americans are sort of last minute shoppers you know.
in the 2 years that we have had our hybrid we have really seen a drop in the MPG, she used to get mid 50's on the interstate and now she has dropped to high 40's, maybe low 50's if she drives 60 mph constantly, plus its been keyed a bunch of times cause I gues most people that own the Prius are assholes I reckon
in the 2 years that we have had our hybrid we have really seen a drop in the MPG, she used to get mid 50's on the interstate and now she has dropped to high 40's, maybe low 50's if she drives 60 mph constantly, plus its been keyed a bunch of times cause I gues most people that own the Prius are assholes I reckon
G
Guest
I have noticed the same trend with my state's hybrid fleet vehicles. They seem to start off efficient and those efficiency gains seem to be quickly lost with each year they are in service. There is an even greater efficiency loss for highway travel (e.g. > 60 MPH) which comprises the primary use of those vehicles.
JR
To be only sligthly less cynical, oil prices are what they are due to the vaguaries of supply and demand, not to mention instability and war. The point I was trying to make is that world demand for oil is way, way higher than it was even just in 2000. I read in the Economist last week that China's demand has risen something like five-fold in that time period, and is expected to more than double again in the next few years. Thus, I agree that the price of oil isn't going to drop if we all start driving Priuses. But, if we stop using so much oil, we can affect the demand equation, and also delay the inevitable drop in supply. So, over the long run, we very well could pay less for oil if we all started driving Priuses today ... not to mention we would be buying less to begin with.If we all bought a hybrid tomorrow, we would see the same rise in gas prices due to folks buying less gas and the oil folks wanting to keep their gold plated yachts, would just charge more. This is overly cynical but I really think there will be some sort of email to the President when we get to within 5-7 years of oil supply left and then some alternative mode will be created, Americans are sort of last minute shoppers you know.
in the 2 years that we have had our hybrid we have really seen a drop in the MPG, she used to get mid 50's on the interstate and now she has dropped to high 40's, maybe low 50's if she drives 60 mph constantly, plus its been keyed a bunch of times cause I gues most people that own the Prius are assholes I reckon
TouchDown
Is it Friday yet?
I know this comment isn't going to go over that well, but I for one don't think gas prices are high enough. The average American bitches and moans about how high prices are to fill up their cars but they don't want to take it upon themselves to actually help out their own cause. And no, I'm not advocating that everybody needs to go out and buy hybrids. Most people can save money on gas by just being mindful of their driving habits. Don't accelerate like a bat out of hell when the light turns green just to race towards the next red light, slam on your brakes just to repeat the process. I'm not saying that people reading this do that, but I see so many people on my drive to and from work doing just that. It wastes fuel. You aren't a NASCAR driver, it isn't a race, you aren't trying to beat anyone to that next traffic light. 9 times out of 10 I catch right back up to you and a lot of times I actually go straigh by you since I'm paying attention to when the traffic light will turn green and I never actually stop (and I cruise right on by without ever having to touch the break). It just ticks me off to hear these same people piss and moan that someone (else) should make gas prices lower. These same people could be saving themselves money if they would only use their brains.
Like what has previously been stated, there have been dramatic gains in fuel economy over the last 20 years, but that gain hasn't been seen as an increase in miles per gallon but rather it's been seen as an increase in horsepower, because that's what the average consumer has wanted (I'm guilty of this too). Higher gas prices may force people to consider vehicles that get better fuel economy instead of power. Only time will tell.
I don't drive a super fuel efficient vehicle, but by just paying a little attention to my driving habits and making sure that my car is in tip-top shape I do pretty well at the pump.
Like what has previously been stated, there have been dramatic gains in fuel economy over the last 20 years, but that gain hasn't been seen as an increase in miles per gallon but rather it's been seen as an increase in horsepower, because that's what the average consumer has wanted (I'm guilty of this too). Higher gas prices may force people to consider vehicles that get better fuel economy instead of power. Only time will tell.
I don't drive a super fuel efficient vehicle, but by just paying a little attention to my driving habits and making sure that my car is in tip-top shape I do pretty well at the pump.
maryannette
Wise One
^^^ Very appropriate for earth day post.
csb
Well-known member
Mine got keyed too. I blame on the guy with the giant truck who always parks next to me in the lot. It happened AT work.in the 2 years that we have had our hybrid we have really seen a drop in the MPG, she used to get mid 50's on the interstate and now she has dropped to high 40's, maybe low 50's if she drives 60 mph constantly, plus its been keyed a bunch of times cause I gues most people that own the Prius are assholes I reckon
I'm feeling old when I say, "Back in 2002, I bought gas for $1.55 and I thought that was EXPENSIVE." That was only six years ago! I would just about kill to pay $1.55 for gas. My 15 gallon tank is now a $50 fill up. Bah.
TouchDown
Is it Friday yet?
RW - I agree. Our infrastructure has been built around the auto. When I was in Singapore 4 years ago, the cost of gas was about 3X here in US, and I've heard that Europe is similar. Eventually, the cost will force us into a change of habits. Up until now, we have been pretty tolerant because the absorbed cost for the changes has been low enough... Not anymore. As Mary has pointed out, carpooling, or others have pointed out even riding bikes... I wish mass transit was more of an option in many areas, but it's just not an option everywhere.
Tire pressure and accel / decel rates, new air filters... all can improve your existing vehicle.
Agree as well that hybrids are not the answer, they will use coal fire electricity to offset dependency on foreign oil, but still require energy generation.
I know a few hourly workers who talk about their 50 mile 1 way trip to work every day and I don't know how they can afford to work for $20/hr. Since they drive a truck, the gas bill eats up 1 hour of your daily pay or about 12%.
Definitely no easy answers.
Tire pressure and accel / decel rates, new air filters... all can improve your existing vehicle.
Agree as well that hybrids are not the answer, they will use coal fire electricity to offset dependency on foreign oil, but still require energy generation.
I know a few hourly workers who talk about their 50 mile 1 way trip to work every day and I don't know how they can afford to work for $20/hr. Since they drive a truck, the gas bill eats up 1 hour of your daily pay or about 12%.
Definitely no easy answers.
I think you guys are all still missing the big picture. Even this morning on NPR, there was some executive from Shell stating that his company's projections are that global oil supply will plateau around 2015-2020 (I guess those earlier projections were correct). With the ever-rising demand from China and other developing nations, Shell is predicting not only continually increasing prices, but major global unrest as well, once the major economies of the world start grasping for control of what's left. Hybrids or not, we're all going to have to learn how to use less oil, and it's going to have to start pretty soon.
And that, my friends, is my Earth Day message. It goes far, far beyond the "environment."
And that, my friends, is my Earth Day message. It goes far, far beyond the "environment."
Katiebug
Well-known member
The much-vaunted "hydrogen economy" only works long-term if you have a non-fossil fuel means of generating that hydrogen. You can either use fossil fuels, or electricity generated from fossil fuels, nuclear, or renewable energy sources to crack water. A PEM fuel cell bus with a built-in reformer will take regular gas, all right - but the reformer takes a half hour to get up and running, and you STILL have to put gas in the thing!
I took a fuel cell engineering course in 2002 as an undergrad, and when we did the calculations out for PEM fuel cells in every car existing on the planet today, it required roughly 3X more platinum (for the catalyst) than exists in the world. Water management is also an issue for PEM cells. That's aside from the issue of how the heck to generate hydrogen fuel without using fossil fuels in the process (either raw materials or power). Biohydrogen is promising but still in the early stages.
I'm a fan of nuclear power. We should be building new reactors, of newer and safer design than what are operating today. Give us pebble-bed reactors and other technology for safe nuclear power! Nukes can generate electricity for electric cars, or to crack water for hydrogen fuel. It has more pros than cons, IMO.
That leaves us with alternative fuels or hybrids. I like the idea of a hybrid, but they're not miracles - hybrids get better mileage in-town than IC engines, because the regenerative braking charging the battery each time you hit a stoplight or stop sign. For the soccer mom toting the kids around town, a hybrid might make sense. For the worker with a long highway-based commute, maybe not. I'm intrigued by plug-in hybrids - VERY intrigued. From a cost standpoint and on a large scale, battery-operated cars and plug-in hybrids make more sense than an IC hybrid.
I like diesels...Europe has really brought diesels a long way. VW's TDI engine is pretty spiffy. I have two friends with TDI Jettas who have been very pleased. They don't smell and the mileage is very nice.
My sister-in-law drives a Chevy Tahoe and that thing just sucks gas down like you wouldn't believe. It's not like she NEEDS a full-sized SUV, either - a social worker with one baby and a dog simply doesn't require that kind of cargo capacity. So many people these days have an SUV or van to drive around their one or two kids. When I was a child, my parents drove two kids and a cocker spaniel in a Chevette! We never had anything but compact or mid-size sedans and station wagons when I was a kid. My brother is single and does not need to haul anything - yet he wants to trade in his Neon for a full sized pickup truck, "just because" he wants one. People seem to want bigger, more powerful vehicles these days, yet they complain when it costs a fortune to fuel them! Mr. Bug and I figure that our Toyota Camry and VW New Beetle will be perfectly fine vehicles unless we have more than 2 kids - by which time we'd need new cars anyways. Yes, I'd like an SUV - but I don't need one, and it doesn't make sense to get one and spend so much more in gas if I don't have a darned good reason.
I took a fuel cell engineering course in 2002 as an undergrad, and when we did the calculations out for PEM fuel cells in every car existing on the planet today, it required roughly 3X more platinum (for the catalyst) than exists in the world. Water management is also an issue for PEM cells. That's aside from the issue of how the heck to generate hydrogen fuel without using fossil fuels in the process (either raw materials or power). Biohydrogen is promising but still in the early stages.
I'm a fan of nuclear power. We should be building new reactors, of newer and safer design than what are operating today. Give us pebble-bed reactors and other technology for safe nuclear power! Nukes can generate electricity for electric cars, or to crack water for hydrogen fuel. It has more pros than cons, IMO.
That leaves us with alternative fuels or hybrids. I like the idea of a hybrid, but they're not miracles - hybrids get better mileage in-town than IC engines, because the regenerative braking charging the battery each time you hit a stoplight or stop sign. For the soccer mom toting the kids around town, a hybrid might make sense. For the worker with a long highway-based commute, maybe not. I'm intrigued by plug-in hybrids - VERY intrigued. From a cost standpoint and on a large scale, battery-operated cars and plug-in hybrids make more sense than an IC hybrid.
I like diesels...Europe has really brought diesels a long way. VW's TDI engine is pretty spiffy. I have two friends with TDI Jettas who have been very pleased. They don't smell and the mileage is very nice.
My sister-in-law drives a Chevy Tahoe and that thing just sucks gas down like you wouldn't believe. It's not like she NEEDS a full-sized SUV, either - a social worker with one baby and a dog simply doesn't require that kind of cargo capacity. So many people these days have an SUV or van to drive around their one or two kids. When I was a child, my parents drove two kids and a cocker spaniel in a Chevette! We never had anything but compact or mid-size sedans and station wagons when I was a kid. My brother is single and does not need to haul anything - yet he wants to trade in his Neon for a full sized pickup truck, "just because" he wants one. People seem to want bigger, more powerful vehicles these days, yet they complain when it costs a fortune to fuel them! Mr. Bug and I figure that our Toyota Camry and VW New Beetle will be perfectly fine vehicles unless we have more than 2 kids - by which time we'd need new cars anyways. Yes, I'd like an SUV - but I don't need one, and it doesn't make sense to get one and spend so much more in gas if I don't have a darned good reason.
