55 MPH: It's time to bring it back.

Make the cars less powerful at the same time! Cars that can do an easy 150mph accelerate effortlessly to 70-80-90, which would explain why drivers get so frustrated at the thought of going a bit slower.

Only ways to make people drive slower is with a carbon tax or through a coercive authoritarian police state. Take your pick.

"Design loads and lane widths could be adapted to the smaller vehicles. Three lane highways might become four lane; more capacity for the price of a can of paint."

Not while big rigs are still used to transport goods cross country which won't stop any time soon.

I'm all for sustainabliity in all other realms, but for the record, I'm all for driving 90mph while traveling cross country via interstate (which I do in an `86 VW diesel on veg oil).

Not gonna work. The benefit has to be encapsulated....not one of us is thinking about bridges when merging onto a highway during our morning commute.

I remember 55....and that everyone continued to drive 70-75. And my car gets 29mpg highway whether I drive 55 or 70....ECU-controlled ignition systems map air-fuel mix for optimal efficiency the way our old carbeurated engines (or early fuel injection systems) ever could. I drive a sensible, safe European car.

I say, build the train anyway. I'd love to ride Boston to Chicago, Washington or Seattle at 200 mph.

And smaller, lighter cars....good. Way good. As long as they can keep me safe for when my neighbor clobbers me in his Bummer or Ford Excretion.

Speed does not kill, it is very sudden acceleration or deceleration which does!

Either way when I am in the Ozark Mountains, I am a NYer, I drive 55 over the immense distances it takes to go anywhere just to save gas, it really does help.

Of course a jeep is an areo dynamic brick so results may very.

A better idea might be the "Is this trip necessary?" kind of campaign, although retail stores would be angry at that.

Perhaps government grants to software developers to create a trip-planning portal that integrates information about shopping and attractions based on distance.

People are wired to drive at 75-80. 55 if fatiguing and irritating for me.

I agree-- the speed limit should be lowered to 55. The only time going 5 miles per hour faster makes a difference is when you are traveling for many many hours. When you're traveling locally (as most people in their cars do) you'll only get somewhere 1 to 2 mins faster. Not worth the effects on the environment (or my wallet with gas costs) if you ask me.

I have always wonder why in Canada, the highest speed limit we have is 100km/h but we the goveners on our cars don't kick in until like 175 I believe. Why not make that 110 or max 120 km/h? There is certannly no need for anyone to do faster then 120 km/h.

If the automative industry has to goveren all engines out at 120, whats the point of making one that can do 200?

I think that would be a better approach then changing the speed limits, although speed limits are not a big issue for me, as I often don't break them on my fixed geared bike...

Bad idea! I would rather drive less to save that 5% of fuel than drive slower. I think the suggestion alone is dangerous because so many Americans already feel like they have no spare time left at the end of the day from such busy lifestyles that asking them to donate more time in traffic for the environment would just make them resent environmental ideas and solutions even more and give them the false impression that these ideas are inherently unreasonable.

As someone who works for a Fortune 50 company that has a lot of eco-friendly initiatives and sustainability on the mind, I can tell you that there is a lot of low hanging fruit we need to tackle first, things that people can feel good about without compromising that will change their minds and help the environment before we even begin to ask for sacrifice.

Why not start by everyone proposing LED streetlights at their caucuses and pushing hard for that? It can save taxpayers money on their state's electricity bill (less than a 4 year ROI,) make a profound environmental difference, and provide a more attractive and higher quality light? If we focus on an easy change like that, where you have very little resistance after explaining why we should do it, we can get people thinking green and feeling good about it in no time! Change doesn't need to be painful!

(And just for the record, I offset with a TerraPass to alleviative some of the guilt over speeding home every day)

I will admit that it is very easy to get used to driving at 75mph but I have found that when I drive a slower 65mph my commute is much more relaxing. I would have no problem with the NJ Turnpike going back to 55mph. My commut would become so leisurely I could read a magazine while driving!

You obviously don't live out in the west where states are 400 miles across and it takes over 5 hours to cross one at 75MPH. Take speeds back down to 55, and you increase that number to over 7 hours.

Stop trying for "one size fits all" solutions to our problems.

55mph - actually more like 50mph - is the most efficient speed for most vehicles. I've seen this in practice while driving my own vehicle that has a couple different instantaneous/average fuel efficiency readouts. It's quite dramatic how much your mpg drop with an added 10mph.

I'm also a sailor and know that wind power increases exponentially with speed, so the faster you drive, the more work the engine has to do to overcome wind resistance. Above ~50mph is where this becomes increasingly more difficult.

blueshift says: "my car gets 29mpg highway whether I drive 55 or 70"

Ummm.... just because the sticker says "29mpg highway" doesn't mean.... you can't be serious.

Some places could use a reduction in speed limit just to help keep people from crashing into someone while racing to get their Starbucks (*cough*San Diego*cough*). However, I don't think a change in speed limit would make much of a difference in places like Los Angeles where most people spend a lot of their commute time creeping along because the highway's packed. Speed limits are actually a very regional thing. I think I would have torn all my hair out if I'd have had to drive the length of I-40 at 55 miles per hour. I think time and energy could be better spent on other campaigns first.

The answer is not with law enforcement -- everyone hates being told what to do, and being stopped by the police blows hard enough that increased enforcement will always be unpopular. The answer is on the supply side -- simply mandate mpg requirements, but enforce those requirements across all speeds. That way, if a gas guzzler can't meet the requirements when going 70mph, make the car companies put a speed limiting device on the car to make it impossible to drive faster than 55mph. On the other hand, if an electric car can go 120mph with zero emissions and no gasoline, more power to it. It would be the ideal incentive for people to buy electric cars -- the ability to drive faster.

I'm sure law enforcement wants it... more tickets!!! $$$

What about a less noticeable, less extreme (to the general populace and politicians, that is) limit of 70 mph or 65 mph. Sure, it wouldn't save nearly as much fuel, but it would save some, and it would ease the public into conserving more than the drastic shift to a 55 mph limit.

I think smart urban design and smart car design and smart transportation design are more important than speed limit.

randykato's triplepost argues the need for a better comment system. Are you listening, treehugger?

LA: people who have the typekey accounts can do their own approval. When I get around to it I remove the duplicates, and have done so.

Rob says:

People are wired to drive at 75-80. 55 if fatiguing and irritating for me.

No they're not. If they were, then the fatality rate wouldn't go up 38% at that speed. If anything, people are wired to drive at about 20 MPH. Maybe 35. Beyond that, our slow reflexes and enormous capacity for making mistakes becomes dangerous to ourselves and the people around us. Otherwise freeways wouldn't even be necessary, we could just build roads however we like and not worry about the consequences of putting that many cars driving in opposite directions in such close proximity.

Something else that people are wired for, is impatience. *That* is what you're complaining about. If we could teleport ourselves instantly over thousands of miles like in Star Trek, travelling interstate at 80MPH would seem astoundingly tedious. People always *want* to go as fast as they can, whether or not they can actually handle it.

Driving 55mph is stupid and I am all for green, but time is money and we don't have enough of it. Adding 10 or 20 minutes to my drive home is time I give up with people and things I care about. My car gets better or equal gas milage at 55-70 anyway so what am I saving? Not Gas, Not Money, Not Time
I'd use public transit if it was economical, efficiant, and on time. Not likely to ever happen with the idiots running it in Orlando.

If it is illegal to speed, why is it legal to build and market cars that do? You can't expect people to drive at or below the speed limit, they simply aren't mature enough to handle driving slowly - a side effect of the 'instant and disposable' culture. I would love to see the speed limit and the top speed of cars both reduced. I'd even favor more draconian punishment. 3 strikes, bye-bye car and license. Driving is a privilege, not a right.

Not enough time to drive slowly? That's almost original, but everyone has the same amount of time. It's how we manage it that differs.

Don't mix your data... Raising speed limits may increase the number of fatalities PER accident, but it lowers the actual number of accidents:

http://www.ibiblio.org/rdu/sl-irrel.html

"Accidents at the 58 experimental sites where speed limits were lowered increased by 5.4 percent."

"Accidents at the 41 experimental sites where speed limits were raised decreased by 6.7 percent."

Furthermore, our road systems are significantly more crowded now than they ever have been. By reducing speed limits, they will become even more congested.

Trains... we need decent frigg'n trains... and we need to stop shipping so much stuff via trucks. Its cheaper to ship by train but shipping companies are forced to use trucks because of regulations enforced by labor unions. It's nuts...

How about updating our highway system? Having a consistent speed limit throughout the day seems inefficient. There needs to be better infrastructure to allow for a continuous update of traffic conditions around urban areas.

When roads are less congested, say during 7pm-6am have the speed limit be 65-75mph. During heavier traffic times, decrease the speed limit to 30-45mph.

Think about how traffic works in regards to congestion. During rush hour times drivers usually drive bumper-bumper in a white knuckle stress period trying to get home with the rest of the crowd. This usually involves heavy acceleration and when the car in front of them brakes they are forced to brake heavily to slow the car in time as to not cause an accident.

Now what if there were a gap between these drivers? More gap means more reaction time to slow down in time to prevent hitting the driver ahead of them. Creating a gap between two drivers means not mashing down the gas pedal thus saving fuel.

If drivers could go in this way there would be less bumper to bumper traffic and an increased flow. Instead of driving at 60mph to 5mph to 35mph there can be a consistent 30-40mph driving on a highway. Less traffic and less stress results in happier drivers and lighter feet on the pedals.

If we mandate our speed limit back to 55mph then we could be moving back technologically! The trade off in fuel economy is less efficiency in transportation and nobody is happy when their UPS/FedEx truck does not come when scheduled. What's the balance between fuel economy and our normal economy?

Our vehicles have come a long way in regards to safety and speed. Let's keep pushing forward with updated, reliable, and efficient technology.

I've always wanted to see a toll road that charged people by the kinetic energy they realized during their trip -- that is to say, by some function of their vehicle's size and speed. But now that I think about it, isn't that exactly what a gas tax would do? And why isn't a gas tax a reasonable alternative to a 55mph speed limit. Lord knows 55mph is the one proposal that makes a gas tax seem appealing.

I think anyone who has the view "I don't want/need/believe in consensual activity X, therefore X should be illegal" is far, far more dangerous than a >55mph speed limit.

First, I'd like to comment on the statements of some saying that they get the same gas mileage whether they drive 55 or 75. That is simply IMPOSSIBLE. It goes against the laws of physics as we know them. A mass moving at a certain speed has a certain energy. That same mass moving at a higher speed (even if it is just an itsy-bitsy higher speed) has a HIGHER energy. And that higher energy means higher gasoline consumption (and more serious car crashes). It is IMPOSSIBLE for a car to get the same gas mileage at 50 as at 70. It is IMPOSSIBLE ALSO for a car to get 'basically' the same mileage at 50 as at 70.

Second, I'd like to second these comments:

'When you're traveling locally (as most people in their cars do) you'll only get somewhere 1 to 2 mins faster. Not worth the effects on the environment (or my wallet with gas costs) if you ask me.'

'Cars that can do an easy 150mph accelerate effortlessly to 70-80-90, which would explain why drivers get so frustrated at the thought of going a bit slower. '

'Something else that people are wired for, is impatience. *That* is what you're complaining about. If we could teleport ourselves instantly over thousands of miles like in Star Trek, travelling interstate at 80MPH would seem astoundingly tedious. People always *want* to go as fast as they can, whether or not they can actually handle it.'

'Driving is a privilege, not a right.'

'Not enough time to drive slowly? That's almost original, but everyone has the same amount of time. It's how we manage it that differs.'

The last four quotes are in my opinion the only things worth remembering about all the comments posted here - the only nuggets of wisdom. Most of the rest was just unabashedly self-serving BS.

55 mph

ahahahahah

no way

this is the year 2008 there is no way we should or will lower driving speeds

cars are designed to go very fast very safely these days

there are many many other ways to reduce fuel consumption but slowing down drivers is insane. Has the poster ever driven on a modern highway ????
If anything we need to abolish speed limits and raise CAFE standards past the pathetic 35 mpg puhlease!

I drive a 1984 car that gets better gas mileage than most cars today.

the pace of life has not slowed in the last 25 years

Sure newer cars are made to handle the speeds but one also must remember that wind resistance (drag) increases with velocity.

So you are likely only getting similar millage from 55-70mph because of your car's design not because you are not expending more energy! (In other words, you're wasting gas going 55 in a car made to go 70.) Cars made before 95, like mine, are designed to go 60 so I get about the same millage from 50-60 and I get half that if I drive 65-75.

FYI: Roads built for higher speeds and weights cost significantly more. Perhaps we shouldn't have undermined trains for shipping stuff?

Really, if you think about it, the speed limits should be RAISED. This is from a purely civics stand point, not environmental. In democracy's the laws should be set at what the citizens desire, not dictations by a higher authority. Every second a HUGE percentage of of drivers are speeding, well aware of the consequences of breaking the law. In other words they are continually committing civil disobedience. Since such a great percentage of citizens obviously disagree with the speed limit by driving faster then it, the laws should be changed to reflect the will of the public they are supposed to be made for/by. Safety, insurance premiums blah, blah, blah, the people practicing civil disobedience are surely aware of the consequences of accidents in the form of death or raised insurance but continue to disobey the law anyway. Government shouldn't take the role of parent or protector making sure we are "safe."

One way I've always postulated speeds could be reduced was through the use of "Pace Cars". Literally a car would be driven by a civil servant (perhaps a police officer) at the speed limit with poles extended from the car to prevent other cars from passing.

About commuters: lowering the speed limit would actually reduce their commute time. Its a weird phenomenom but I'll try to explain it:

In computer chips, there is a phenomenon whereby the time it takes to address an operation increases exponentially while the number of operations in queue increases linearly. Researchers at Bell Labs first noticed it in the late 60s if I recall.

A similar effect happens in traffic, and I've witnessed it personally. You'll be cruising along at say 60mph in dense (but moving) traffic. Someone ten cars up brakes lightly and then the car after that brakes and then the car after that and so on. Each car brakes slightly harder (human nature to over react) until the whole freeway has suddenly slowed down dramatically. This is similar to forcing too many operations (cars) and a computer chip (road) at once. The address (commute) time increases exponentially (sorta).

Dropping the speed limit to 35mph on the Stevenson expressway in Chicago (I90) or on I4 in Orlando would, IMO, cut commute times in half.

"Dropping the speed limit to 35mph on the Stevenson expressway in Chicago (I90) or on I4 in Orlando would, IMO, cut commute times in half."

First off the Stevenson is I55. Secondly, what good would a 35mph speed limit be @ 10pm when there is virtually NO traffic?

"Dropping the speed limit to 35mph on the Stevenson expressway in Chicago (I90) or on I4 in Orlando would, IMO, cut commute times in half."

First off the Stevenson is I55. Secondly, what good would a 35mph speed limit be @ 10pm when there is virtually NO traffic?

It's easy to confuse efficiency with economy. In a modern car, it is entirely possible to get the same MPG at 55 and 70 MPH. This is because gasoline internal combustion engines are least efficient at low throttle openings. Since the horsepower wars of recent years have yielded cars that are ridiculously overpowered for day-to-day driving, a steady cruise at 55MPH has the engine working near the bottom of its power curve. At 70MPH the throttle is wider and the engine is working harder, breathing better, and making more power per unit of fuel. So even though aerodynamic drag has increased exponentially with the increased speed, it's quite possible that the increased engine efficiency (power output per gallon) compensates, resulting in similar overall economy (miles per gallon).
All of this argues for smaller cars (less mass, less drag) powered by smaller engines (which will tend to operate higher up the power curve, i.e., more efficiently), all of which will yield better fuel economy.

I would however respectfully disagree with people who think we can tax our way into lower fuel consumption. Americans have proven that our thirst for gas is a pretty inelastic demand; otherwise we'd be using 50% less gas than when gas was $1.50. What would happen is that poor and working-class people would just get shafted even harder, since they're the ones with fewest options as to where to live and where and when to work.

Also -- if you're driving a steady 70 on a highway where everyone is driving a steady 70, you can maintain good fuel economy. But if you're weaving and dodging, sprinting and braking to do 55 where everyone's doing 40, then your mileage will suck. Fuel economy has more to do with driving style than absolute speed.

Proposals that are likely to be percieved as inconveniencing people are a bad idea as they are likely to cause major setbacks in the perception of the green movement. Environmentalists must avoid lengthening people's work commutes or risk being completely marginalized.

It would however not be so bad to limit vehicles weighing over 6,000 pounds to 55mph, as those are work vehicles, not commuter vehicles so the limit would not effect anyone's daily commute. Furthermore the chances of killing someone in another vehicle increase dramatically with the weight of the vehicle. Thus any federal restriction on speed should be limited to heavy vehicles. Truck drivers might even benefit from such a restriction by decreased fuel costs while remaining competitive in shipping speed with other truckers.

For an example of unintended consequences, a while back they decided to regulate the amount of water consumed per flush by toilets. The result was that for several years it was impossible to legally buy a new toilet that didn't need to be flushed multiple times do do its job, wasting a lot of water. These sorts of regulatory steps do far more harm than good by creating ill will towards environmentalism at large.

The 55 mph speed limit could have similar unintended consequences. Lower maximum speeds mean more cars on the road at a given time, which means an increase in the frequency of gridlock traffic, which could ultimately result in a great deal of wasted gas.

The ideal solution is actually an oil import tariff, as it targets the nonrenewable portion of fuel in a straightforward manner. This would result in the heavy vehicles that damage the roads the most being taxed in proportion with the damage that they do. With an oil tax no fuel could masquerade as renewable while actually using substantial oil inputs, nor would a truly renewable fuel be taxed simply by virtue of not having been popularized at the time the tax code was written (ie. biobutanol or oil from TDP). Increasing the costs of oil in a predictable and permanent way would greatly encourage the development of renewable sources of both fuel and materials. Any such oil or fuel tax should transparently be given back to the people evenly, for example by using the money from a $10/barrel import tariff to exempt the first $20000 in income from social security taxes. This way people who don't drive a lot will see the new oil tax as an opportunity to actually lower their tax burden.

John B got it right, houston was half right. When 2 bricks are traveling at 50mph, the force to move them is equal. when one increases to 70mph, the force to move it also increases based on friction (wind, rotational mass, and others).

However, if an egg and a brick travel at 50mph, the force to move the egg is far less due to a lower air friction co. Let's apply this:

My '90 Protege at 60mph will net 35mpg. My '02 Grand Prix at 60mph nets 30mpg. Seems a crock doesn't it? let's increase the speed.

At interstate speeds (70mph) the Protege nets 31.6mpg. At the exact same time I tested the Protege, my girlfriend was driving the Grand Prix. It obtained 34.5mpg over the same stretch. The GP was in front, breaking the wind for the Protege, which followed 3-4 car lengths behind over the course of 500 miles; Portland to Cour De' Lane.

Can we assume that Houston's other statements are bunk because he/she didn't understand physics in complete? no. But I do wish they hadn't claimed to understand the "law of physics as we know them." I'm afraid that makes you seem ignorant, because "we" as in "we the car manufacturers" understand them in a greater detail than you.

The radio button states "Post an intelligent and civil comment." Please be sure to follow both criteria next time. Thank you for your understanding.

1) What about stricter driver education and testing first? We all know there are people out there who should not be behind the wheel. Sure, they can pass a computer test and parallel park a Dodge Omni, but can they handle typical speeds and situations? It's a serious endeavor.

2) Go Autobahn style and get the slow folks out of the fast lane and enforce left lane passing. "Drive right, pass left."

3) Enforce lane signaling. Basic communication.

4) Breathalyzers on all cars.

It's pathologically insane how people drive faster because they're in a hurry to get to work to make money to be able to afford things like their car and gasoline so they can drive faster. So they work harder, spend less time with family, pay taxes to support our defense spending so that our troops who are separated from their families can secure our oil interests and die or get injured in the process so that we can drive faster and die or get injured in the process. Count the fatalities on our roadways and I'd say it's War out there!

I love the delusion some people live in.

I don't mind driving slower. Hell, I don't mind walking when the weather is nice. There are a lot of nice places to see.

I say make roads and cities pedestrian friendly. Heck, put in a bike path or two.

I'm a strict vegetarian who doesn't drink sodas. So, I don't need an SUV or Hemi to cart around my fat ass around with my burger, fries, soda and ice cream.

You can't legislate sense into people (although they try). People will still drive as fast as they fell they can go. And it will be dangerous for those who obey the 55 mile/hour law because everyone will be zooming past them

The better alternative is to build more mass transit and more fuel efficient vehicles. I welcome the price of high gasoline because that will spur these developments.

"First, I'd like to comment on the statements of some saying that they get the same gas mileage whether they drive 55 or 75. That is simply IMPOSSIBLE. It goes against the laws of physics as we know them. A mass moving at a certain speed has a certain energy. That same mass moving at a higher speed (even if it is just an itsy-bitsy higher speed) has a HIGHER energy. And that higher energy means higher gasoline consumption (and more serious car crashes). It is IMPOSSIBLE for a car to get the same gas mileage at 50 as at 70. It is IMPOSSIBLE ALSO for a car to get 'basically' the same mileage at 50 as at 70."

Others have addressed this so I'll just skim this. Mileage is affected by driving habits but also by vehicle design. I used to have a 1972 Oldmobile Delta 88 (Land yacht, longer, wider, and heavier than a Chevy Suburban) and the faster I went the better the mileage. Why? Because the engine how more effeicent at higher speeds and at low speeds I was just wasting fuel, you'll find the same issue with most SUVs and trucks today where there is very little mileage difference between 55 and 70 because at 55 energy is just being wasted by the larger motor.

Now I speed, I will freely admit it, in fact I was just pulled over for 80 in a 65 the other day. However I do find that I get much better overall milage when I'm not having to constantly jocke