Future Audis may time traffic lights for you

Here's a trick efficiency-chasing hypermilers have been using for years: spotting the cycles of stoplights from 100 to 200 yards out and letting the car coast up to the light just before it turns green, then carrying on without ever letting the car come to a complete stop. These hypermilers, along with professional truck drivers, do this because they know that accelerating from a standstill burns the greatest amount of fuel, and because letting a car coast up to the light with the automatic transmission downshifting by itself is easier on the transmission than stomping on the brakes right beneath the stoplight. Oh, and it's easier on the brake pads as well.

Now, if only there was a way to always keep track of traffic light changes and plan accordingly...

It seems Audi is on to this little gas-saving trick, to the point that they've developed a system that doesn't require the driver to have 20/20 vision to spot stoplights from afar. The Audi Online traffic light information system links up with a city's traffic light network, and can tell you the optimum speed in order to make the next green light. And when you're sitting at a red light, the system counts down to the second that the light will turn green. Furthermore, the system knows how long the light will stay red, so it will make the car's start/stop system shut down the engine until 5 seconds before the light turns green again.

Audi
The system will tell you ahead of time whether you'll have a red or a green light.

Audi predicts that the system will not only save time, but also result in a 15 percent reduction in CO2 emissions. The system is basically production-ready and pending an, ahem, green light from the relevant government agencies. Currently, Audi is testing it in real world condition in a number of cities including Berlin and Las Vegas. Of course, the system depends on a city's electronic infrastructure as it needs a live connection to a traffic light computer, so a hamlet in rural Vermont with two stoplights is unlikely to tell your Audi anything.

Audi exhibited this system in prototype form at the Consumer Electronics Shows in Las Vegas in January of this year, though at the time the company did not say when we can expect it in production cars.

By Jay Ramey