ddrueding
Fixture
There is a flaw in this assumption as well. There will be more people on the roads because there will be more people. This is the problem we most desperately need to fix.
Why C.A.F.E Standards are Dumb
- Thread starter Clocker
- Start date
There is a flaw in this assumption as well. There will be more people on the roads because there will be more people. This is the problem we most desperately need to fix.
Howell
Storage? I am Storage!
Those two are almost comparable...
Why doesn't the gov't rework our roads so people don't spend time stopped at traffic lights or in stop and go traffic wasting gas? Cars get much better fuel economy running at a constant speed instead of constantly accelerating. They could save more oil by improving the flow of traffic than by changing the C.A.F.E. standards to 35MPG and the effect would take place much sooner, and for all vehicles on the roads, not just the new cars that C.A.F.E. standard affects.
You can't be serious about this. You can do what you suggest. Just get on the interstate and drive until you have had enough. The rest of us are actually trying to go somewhere.
Howell
Storage? I am Storage!
Why not just produce a vehicle with adequate proportions of the three?
ddrueding
Fixture
You can't be serious about this. You can do what you suggest. Just get on the interstate and drive until you have had enough. The rest of us are actually trying to go somewhere.Those two are almost comparable...
Why doesn't the gov't rework our roads so people don't spend time stopped at traffic lights or in stop and go traffic wasting gas? Cars get much better fuel economy running at a constant speed instead of constantly accelerating. They could save more oil by improving the flow of traffic than by changing the C.A.F.E. standards to 35MPG and the effect would take place much sooner, and for all vehicles on the roads, not just the new cars that C.A.F.E. standard affects.
Howell, I have to assume that you are misinterpreting to make a point? If so, I don't get it.
I live 1 mile from the freeway. On that mile there are about 10 traffic signals. I burn many times more fuel idling and accelerating 10 times than I would driving the mile directly. Optimization of the network would certainly help, and it would benefit all existing cars as well as new more efficient cars.
Stereodude
Not really a
Stereodude
Not really a
Isn't that what we have now in your standard average mid size car? Note they don't get 35MPG though. Which are you willing to give up to get to 35MPG or better?
Stereodude
Not really a
How come no one suggested lowering the speed limit? That would be the easiest and have the most immediate effect on fuel consumption. And, all the local towns could watch their revenues skyrocket on tickets.
http://www.storageforum.net/forum/showpost.php?p=96922&postcount=47
Gotcha covered. ;-) Safety would improve too.
jtr1962
Storage? I am Storage!
Been there, done that. The 55 mph limit was both unenforceable and a massive failure. Enforcement cost more fuel than it saved. It also cost lives, both in car chases and from people falling asleep at the wheel. In all honestly, if we had higher limits like Europe that would lead to more efficient cars. An SUV even at 60 mph gets poor economy. Imagine one at 100 mph, assuming that it even had the power to reach that speed (doubtful given the boxy shape). It wouldn't have the stability, either. My guess is people would willingly give up size to be able to legally go faster.
Howell
Storage? I am Storage!
I would never live in a place where that was routine.
ddrueding
Fixture
Re: Speed limit.
I fail to see how making more people spend more time being unproductive can be done in the name of efficiency.
I fail to see how making more people spend more time being unproductive can be done in the name of efficiency.
fb
Storage is cool
Well, it might not happen the same week as the road opens, but it'll change quite fast. There are plenty of studies made about the subject, as jtr1962 mentioned.
Gas mileage is significantly improved at lower speeds.
http://www.grc.nasa.gov/WWW/K-12/airplane/drageq.html
Stereodude
Not really a
Why not? They've done all sorts of other crazy things in the name of efficiency? Gas Guzzler tax? JTR wants to make gas $6 a gallon in the name of efficiency. The feds are going to raise the C.A.F.E. limit and drive the US automakers out of business in the name of efficiency. Why is the speed limit off limits?
Stereodude
Not really a
Well, I didn't suggest we change only one road. I'm talking about changing all the roads. If you change only one then people will move from their congested road to the new uncongested road until there is some sort of equilibrium. However, if you changed all the roads then in theory you could remove all the congestion from all the roads and there wouldn't be a need for people to change their routes.
Howell
Storage? I am Storage!
I not sure I'd have to give up anything.
http://articles.moneycentral.msn.com/SavingandDebt/SaveonaCar/The100mpgCarIsComing.aspx
Stereodude
Not really a
I would wager there probably isn't a single production SUV that can't go over 100MPH. Most cars can do about 110 or more. Often they can do better, but are limited. My car will do about ~150MPH and it's not small, it's not light, it's not a sports car, and it doesn't have 400HP either.
People wouldn't need to trade anything to go faster.
Personally, I'd love to get my hands on some of the turbo diesels they have in Europe, but the CO2 nazis are going to stop that from happening.
Cars like:
http://www.egmcartech.com/2007/06/26/bmw-6-series-gets-282hp-twin-turbo-diesel-engine/
http://www.egmcartech.com/2007/06/26/bmw-1-series-gets-201hp-twin-turbo-diesel-543mpg/
Stereodude
Not really a
100MPG? That's a big fat lie. If you turn a hybrid into a plug in electric car it's not really fair to rate it in MPG because it's not relying on the burning of gas to move. However, if you want to rate it that way... Heck I'll drive an electric golf cart around that gets infinite MPG.
Howell
Storage? I am Storage!
That Chevy Volt is hot! I hope it comes out soon.
ddrueding
Fixture
Enforcing speed limits and forcing auto makers to make more efficient vehicles is too narrow a scope. Let's restate the problem we are trying to solve:
Petroleum is a limited resource, the consumption of which is bad for the environment.
True?
Why are we so worked up about exactly how we could reduce consumption by a specific market? Shouldn't we be reducing consumption wherever it is most easily reduced?
By making every barrel of oil cost more as it comes out of the ground, we apply pressure in every market for the resource. Those markets where an alternative is more cost effective will be the first to switch. Gasoline's most notable property is it's really high energy density, this makes it very effective in devices that need to carry their own fuel (cars, planes, etc). Why are we still using oil for power plants? Or to heat homes?
Everything that uses oil should cost more. How much more? No idea, but this cost should include factors such as pollution cleanup and impending scarcity. Add on enough to cover cleanup of all pollution to date and research of the technologies to replace it and you are about there.
I'm all for making gas $10/gallon. I'm all for making people pay for what they use.
Not OK? Making it illegal for someone to use a product they bought they way they want. I can buy a hundred gallons of gas, fill a bathtub in my backyard, and let it burn til it's gone. I can do this every day without violating any laws. If this gas costs $10/gallon I'm less likely to do it.
If you want to ration gas, that would be a middle ground. But don't let me buy gas for an artificially low price and then attempt to restrict only some of the possible uses for the product.
jtr1962
Storage? I am Storage!
Let's assume the weight is 6000 pounds, the frontal area is 30 square feet, and the drag coefficient is 0.7 (about right for the box that most SUVs are).
Rolling resistance = 0.015*6000 = 90 pounds
Tire flex drag = 0.0001*speed*weight = 0.0001*100*6000 = 60 pounds
Aero drag = 0.0026*frontal area*Cd*speed² = 546 pounds
Total drag @ 100 mph = 696 pounds
Horsepower = drag*speed/375 = 185.6 HP
Horsepower at engine (90% transmission efficiency) = 185.6/0.9 = 206.2 HP
How many mid-size SUVs have 206 HP (actually you probably need closer to 225 HP once you count the other loads on the engine)? I'm sure there are some that don't. Car & Driver posts top-speed results in its tests. That might be a good source to look this up.
The same calculations give 57.3 HP at 60 mph. That basically means if the SUV gets 12 mpg at a steady 60 mph it will get only 5.6 mpg at 100 mph. And it'll need at least 206 HP to even reach 100 mph. Even if hypothetically an SUV could reach 100 mph, driving it at that speed would be ridiculously expensive. Something like an Escalade might need 250 HP, a Hummer 300 HP. You might as well tow a fuel tanker behind you if you want to do 100 mph in any of those.
Interestingly, GMs defunct EV1 managed 186 mph on a little 65 HP electric motor with only the addition of wheel covers.
ddrueding
Fixture
I can testify to a 1997 Chevy Suburban towing a sailboat bouncing off the speed limiter at ~107mph 
jtr1962
Storage? I am Storage!
jtr1962
Storage? I am Storage!
Yep, as Clocker said earlier the automotive transportation sector is only a small part of the picture. It may be one place to start but there are loads of other areas we have to deal with:
1) Railroads in the US are by far the biggest consumer of diesel fuel. Diesel fuel has already past the price point where it costs less long term to electrify on many Class 1 freight railroads (Union Pacific, BNSF, CSX, Conrail, Norfolk Southern,to name a few). The problem is that RR executives are among the most shortsighted. They can't see past the next quarter, so they won't invest the million dollars or so per mile that electrification will cost because the payback time will exceed their tenure. Maybe some forcing of their hands here, coupled with tax incentives or subsidies, might be a good thing to get these railroads electrified. And as a plus, the faster possible service might take some priority freight off the roads. And those who live along the tracks will welcome the relative silence of the electric locomotives compared to the racket from the diesels.
2) Power generation. Why are we using coal and oil to make some of our electricity? Nuclear can cover anything not already covered by wind, solar, or hydroelectric. And geothermal is a vast, untapped resource here. Why not give some incentives to try that?
3) Aeroplanes are another huge fuel consumer. Electrification of freight lines will make faster passenger service possible. Building dedicated high-speed lines can reduce domestic air travel substantially while offering equal or better door-to-door speed on trips under up to 1000 miles. We can't get rid of air travel, but we can pretty much offer comparable alternatives for everything except overseas travel. The maglev in a tube idea will work longer term, but that's a huge investment. We can do the other things right now.
4) Ships definitely are huge consumers of diesel fuel. The large ones can be converted to nuclear power easily. The nuclear navy proves it can be done safely. Why not go this route?
5) Energy conservation in homes. More efficient appliances are all good and well but lighting is a huge power drain. LEDs promise to reduce that substantially and look poised to make incandescents obsolete within 5 years, fluorescents within ten to fifteen. If possible accelerate these trends, and outlaw inefficient lighting once LEDs can do the job. Since PCs were mentioned, maybe we should start offering green PCs. We can build low-power 1 to 1.5 GHz machines which as a bonus can be passively cooled (i.e. totally silent). They will still be fast enough for most home uses, except maybe cutting edge gaming. Why aren't these made now? I might buy one. The silence appeals to me more than the low power usage. SSDs promise to reduce power consumption still further.
There's a lot more, but I'm tired of typing. :crap:
fb
Storage is cool
It doesn't really matter if you improve five or 1000 roads in a large city, the traffic will increase until the main roads are congested again. It's exactly the same with buses and trains. If you build it, people will eventually travel with it even if there was no initial demand.
Stereodude
Not really a
Probably all of them, hence my earlier comment.
Stereodude
Not really a
Stereodude
Not really a
Because the same people who are upset about global warming and the burning of fossil fuels are vehemently opposed nuclear power.
Apparently we're supposed to go back to the mid 1800's ride horses and not use electricity.
ddrueding
Fixture
But they put out methane! We'll need to retrofit a filtration device (I'm sure they'll love that).
Stereodude
Not really a
But the environment was so much better back then!But they put out methane! We'll need to retrofit a filtration device (I'm sure they'll love that).
or was it?
ddrueding
Fixture
This is important. It was better back then because there were less people. If there are only a million people on the planet, they can be doing pretty much whatever they want for as long as they want. The more people, the less each can pollute/consume. At some point, less people is going to be easier than more efficient.
Howell
Storage? I am Storage!
But they put out methane! We'll need to retrofit a filtration device (I'm sure they'll love that).
I'll handle filtration if you handle collection.
Stereodude
Not really a
So, why aren't all the greenies killing themselves off?
Stereodude
Not really a
C'mon even an H2 has a Cd of .57...
Stereodude
Not really a
As soon as they come up with a fuel for the reactor that can't be used or converted into something that can make nuclear weapons I'm all for it. However, I think that's probably a ways off.
Chevy Tahoe is 0.363
jtr1962
Storage? I am Storage!
I'll defer to your knowledge since this is your field of expertise, but I'll admit to finding that a little hard to believe. Something pretty well streamlined like the EV1 is 0.19. What is basically a box with a few rounded corners is not even twice that? :scratch: For reference a diesel locomotive, which is pretty much a box with a nose on it, is widely accepted to have a Cd of 1. I thought I was being very charitable with my 0.7 estimate. I had actually planned to use 0.9.
Any idea what the Cd for the Scion is? Among the comments I've heard about that vehicle are "Nice box. Now where's the car that came in it?" :bglaugh:
Cd is an oft abused term. You should probably use cdA (A = area). For two vehicles with nominally similar cd, this looks good on paper, but if one is a mini-car and the other is AN SUV, the SUV will have much more drag to overcome == more fuel, which mean more power == larger power plant, heavier construction to support larger loads == more weight == larger power plant == more fuel, and so it goes...
It's not simple
It's not simple