If you commute down the same long street every day, you might eventually start to crack the code of the traffic signals: At the right speed, depending on the time of day, you can keep hitting green lights. But it’s a tricky thing to do on unfamiliar roads or with less predictable lights. New tech from Audi may soon be available to help tell you what the next light is going to do—both making drives a little less stressful and cutting pollution.
Audi’s Traffic Light Assist uses Wi-Fi in a car to hook up with a city’s smart traffic light system and then displays the speed you should be driving to make the next light. Though it may seem like a small change, this driving behavior can actually save a lot of gas. "You’re going to be able to avoid racing to get to the stoplight, missing it, and then sitting there burning off all that extra fuel," says Bradley Stertz, corporate communications manager for Audi.
If you do get stuck at a light, the system will automatically turn off your car—saving even more gas—and then turn back on a few seconds before the light turns green. A display on the dash will tell you how much time you have to wait.
In theory, the system could also be used to tell a light to change when you're the only one there, using the same method that emergency vehicles use to keep lights green, but that would depend on what a city is willing to allow. City laws and infrastructure are the biggest challenge to using the technology at all.
"The technology is there, it's just a matter of whether the infrastructure is ready," says Stertz. "Some cities aren't equipped yet, but if there is a traffic congestion benefit and lower emissions—especially in areas where there might be smog problems, we think it's something that will get good consideration."
In total, the system could reduce a car's CO2 emissions by 15%, according to Audi. If everyone in Germany used the system, it would save about 900 million liters of fuel.
It isn't the first system to try to give drivers access to traffic light info; a few cities have electronic roadside signs displaying the recommended speed to catch a green light, though they tend to be expensive and hard to maintain. Another system, from researchers at MIT and Princeton University, uses smartphones mounted on windshields to crowdsource info about lights through the cameras on the phones. Though that app, called the SignalGuru, has the advantage of not relying on infrastructure, it also has several technological challenges. Audi's system may be most likely to actually make it into everyday use.
The company is currently testing it in Berlin and in Verona, Italy, and plans to test it in the U.S. soon.