Networked Traffic Lights Could Save Time, Fuel, and Lives


Photo: Flickr, CC
Dumb Traffic Lights are so Passé
After smart grids, smart sewage and smart lights, here comes the smart traffic lights. To be fair, many lights already have some sensors and can adjust their cycles based on feedback from the road, but what I'm talking about here is on a whole other level. BMW and Siemens unveiled a system of networked traffic lights that can communicate with nearby cars to warn them about road conditions, help them better use anti-idling features, but that can also learn about traffic patterns from those cars and adjust cycling times to optimize traffic flow, saving time and fuel.

Photo: Flickr, CC
Dave, the Car Ahead is Warning Me About...
Such a system could also be expended to have cars talk directly to each other ("Car2Car" instead of "Car2Infrastructure"). This could mean that a car slipping on black ice could warn cars behind it about the traction conditions so they could know to slow down and be careful.

But back to the traffic lights: If a car is equipped with anti-idling technology (aka stop-start), the fuel-saving potential can be maximized by knowing about the light's cycle.

The function presently switches the engine off as soon as the car is stationary and the driver releases the clutch, with the engine restarting when the clutch is depressed. If there are only a few seconds between stopping and starting, however, it is more energy efficient to let the engine run.

At the same time, vehicles could send back information to the traffic light, e.g. position, direction and speed of the car, which can be used to optimize the traffic flow and to adapt the cycle time of the traffic light.

Reducing Friction on the Road - It Adds Up
Making traffic flow more efficient by having traffic lights that are constantly adapting and talking to each other so that vehicles get as many green lights in a row as possible, that might sound like a small thing, but if you multiply the time and fuel saved for each car by the number of cars on the road, that's pretty huge. Same for the number of lives saved by making cars and intersections safer.

If this gets combined with the kind of augmented reality windshields and onboard computers that automakers are working on (see here for example), all this information could be given to drivers in a very intuitive and non-intrusive way. You might not even have to take your eyes off the road.

Only a Small Part of the Solution
Of course all of this is just working on a symptom. The real way to save fuel and make roads safer is to rely a lot less on cars. Walkable cities, quality bike paths, fast rapid transit. All of these things are badly needed. But there's no harm in also making car-related infrastructure more efficient and safer.

Via Green Car Congress
More on Greener Traffic Lights
Energy-Saving LED Traffic Lights Potentially Dangerous in Snow Storms
Gary Lauder on the Social and Environmental Impact of Stop Signs and Roundabouts (Video)
Fix those Traffic Lights to Reduce Congestion (And Emissions)

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