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A National Speed Limit

July 3, 2008 - by Donny Shaw

Yet another idea to reduce gas prices being kicked around in Congress, the Associated Press reports:

>Sen. John Warner, R-Va., asked Energy Secretary Samuel Bodman to look into what speed limit would provide optimum gasoline efficiency given current technology. He said he wants to know if the administration might support efforts in Congress to require a lower speed limit.
>Congress in 1974 set a national 55 mph speed limit because of energy shortages caused by the Arab oil embargo. The speed limit was repealed in 1995 when crude oil dipped to $17 a barrel and gasoline cost $1.10 a gallon.
>Warner cited studies that showed the 55 mph speed limit saved 167,000 barrels of oil a day, or 2 percent of the country’s highway fuel consumption, while avoiding up to 4,000 traffic deaths a year.
>"Given the significant increase in the number of vehicles on America’s highway system from 1974 to 2008, one could assume that the amount of fuel that could be conserved today is far greater," Warner wrote Bodman.
>Warner asked the department to determine at what speeds vehicles would be most fuel efficient, how much fuel savings would be achieved, and whether it would be reasonable to assume there would be a reduction in prices at the pump if the speed limit were lowered.

Detroit News does the math in an earlier article, figuring that a rational person would have to value their time at less than $12/hour to voluntarily choose to slow down:

>It is classic time-is-money tradeoff, said David Greene, a researcher for the U.S. Department of Energy based in Tennessee. A motorist can save $12 in gas by going 10 mph slower over 500 miles. But it adds an hour to the trip.
>"For a lot of people, their time is still more valuable than the fuel savings," Greene said.

Of course, driving 55 on the highway is annoying enough that a mandate, not rational decision making, would be needed for people to actually begin slowing down. And there’s also a safety issue that such a mandate would solve:

>Police and others say slowing down too much can be dangerous. Some folks are tempting fate by dipping below 55 mph, said Jim Rink, a spokesperson for AAA Michigan. If most traffic is going 70 to 75 mph, the slow car becomes a danger, he said. “It’s a recipe for a potential crash,” he said.

Photo of U.S. 50, “the loneliest highway in the world,” by kla4067 used under a Creative Commons license.

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  • Anonymous 07/05/2008 12:24pm

    national speed limit? yeah, thanks, that’ll fix everything. It’s not like people trading oil as a commodity and intentionally pushing prices higher are a large part of the problem or anything…

  • Anonymous 07/05/2008 2:14pm

    How about enforcing the current speed limits instead??

  • Anonymous 07/06/2008 5:00am

    Air and water cars.

  • chatmandu 07/07/2008 11:57am

    The speed limit should be 60 mph. This would save gas and lives. If 60 mph was the limit then someone doing 60 mph would not be dangerous. Stupid argument about your time being only worth $12 an hour at 55 mph.

  • Anonymous 07/20/2008 5:38am

    What’s so stupid about your time not being worth $12.00? People pay people for services at a much higher rate all the time. For instance if you take your car in for repairs, the rate is at least $70.00 per hour. You pay at least $15.00 for a haircut that takes 15 minutes. What is stupid is us having to do this debate all over again. Your time may not be worth $12.00 per hour, but most people feel differently.

  • Anonymous 10/07/2008 3:32pm

    the answer is simple. slower traffic keep right.
    If people want to drive slower, they can, in the SLOW lane. if they want to drive faster, let them, in the FAST lane. I would even vote for an increased limit in some places.
    keep in mind, in 1910, the national speed limit was 12mph. vehicles are much more efficient now, safer too. maybe it is time to raise the limit in the fast lane?

  • Anonymous 10/07/2008 4:49pm

    I agree with increasing the limit. If you want to drive slow, stay in the right lane.
    My big truck, I drive in the right lane, has a computer and tells me the mpg doesnt change from 55 to 62.
    I set cruise control and go. My daily route is flat, with 1 hill, and no stops in between, my mileage varies less than 1/2 gal/tank, not3.
    I checked this in our newer car, driving on the flatlands, in 2 different states and it actually got better mpg going faster than slower. (80mph limit in Arizona, 35mpg vs the 70mph in California 34mpg.)
    I don’t know what conditions or type of car, the detroit news tested, but I drive alot, Real world experience with a newer vehicle, the difference is not that much
    gas is $4 a gallon here I would have to either let it sit idling or flooring it on the green lights, to use the $12 difference in fuel (3 gallons) per 500 miles. The numbers on this website are more likely. .0018 difference.

  • Anonymous 10/20/2008 4:11am

    i hope you did’nt spend $12.00 wasting your time on this conversation.

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