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Old 09-15-2012, 04:44 PM   #1 (permalink)
redpoint5
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Join Date: Aug 2010
Location: Oregon
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Best Ecomod I Could Make

My nighttime commute home at 1am includes two very inefficient traffic lights. I've included the scenarios below, but understanding them is not important to my main idea.

Scenario 1. On a major road with a 50mph speed limit, there is a 3-way stoplight to allow traffic from a freeway off-ramp to enter. This freeway traffic can either turn left or right at the light. 95% of traffic makes the right turn. The problem is, the light turns red for the main direction of traffic as the adjoining vehicle arrives at the light. This causes main traffic to come to a stop from 50mph just to let someone who is likely turning right (and can turn on a red) to go first. Everyone stops!

This is what the 3-way intersection looks like. Arrows indicate direction of travel.

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Scenario 2. A left-turn traffic light is triggered well in advance of the stop line. This is good, except that it triggers only the lights that go straight through the intersection, and not the left turn lane that I am in. Main traffic is then stopped while nobody travels through the intersection. Main traffic is then given a green light for approximately 5 seconds, and then it is stopped again to finally allow the left turn.

If I approach the left turn light at very high speed and then stomp on the brakes at the last moment, I can get to the second sensor just in time to get the left turn light to change along with the straight light. As we all know, slamming on the brakes is inefficient.

Don't know if this makes sense, but arrows indicate direction of travel, and the curved lines in the middle are the left turn lanes. Ignore the dots; they were required to maintain spacing.

. . . .v . . ^
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<===||((||==<
>===||))||==>
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. . . .v . . ^

Conclusion Each of the two inefficient traffic lights that I encounter on my 7 mile commute likely waste hundreds of gallons of fuel per year. If I am concerned with using finite resources efficiently (which I am), then the greatest ecomod I could make is to change the way the traffic lights behave. Given that these are just 2 lights on my 7-mile commute, it stands to reason that there are hundreds of thousands of lights that could be optimized to decrease traffic congestion, decrease commute times, and decrease fuel consumption. If smarter people than I were put in charge of this, I could imagine a national fuel savings of 5%.

Question Who do I need to contact to discuss traffic control improvements? I travel in both Oregon and Washington states on a regular basis. It seems silly to me that I can come up with better traffic management design when it isn't my area of study or profession. I suppose everyone makes mistakes.

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Last edited by redpoint5; 09-15-2012 at 05:36 PM..
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