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An app that predicts traffic lights for better mpg

articles says they got a 20% bump in mpg by having the app time the lights so you can slow down or speed up to catch the green lights.

What’s going to happen to the world when/if the internet/cell phone services goes down?

While I would expect some improvement, frankly I doubt if it is going to be anything like 20%. Of course that is based on my driving style, yours may be different.

Good Luck

I didn’t see what vehicle(s) they tested, but a large truck might come close to that 20%; A 15mpg vehicle getting 17mpg using the app

Looks to me like just another thing to distract the driver from the road ahead.

How would this help with the people who stupidly accelerate up to each red light or stop sign?

I would take that 20% figure with a grain of salt.
Stopping suddenly to avoid catching a red light can also be a bit dangerous. Not too long ago I started to brake at a right turn when the light suddenly went to yellow.
Since it was one of those split second decisions I chose to make the turn and luckily for me I did. All I saw in the rear view as a turned was a Dodge 4 x 4 pickup whizzing by. If I had stopped suddenly I’d have been shoved clean through the intersection.

The traffic lights here are the worst I’ve ever seen about synchronization and they’ve been that way for decades. On more than one occassion, especially at night, I get tired of sitting and just go on red provided there is nothing approaching.
The lights are all set up to stop traffic block by block and very seldom can anyone go a few hundred yards without touching the brake pedal.

Why would someone brake suddenly to avoid stopping at a red? Hard accel and brake does not help w/ fuel efficiency. Gentle accel and braking is the key. The idea of this app is to promote gentle braking, or coating, up to a red and avoid stopping. In fact, slowing down over a longer distance is more predictable.

Doesn’t everyone pay attention to the timing of traffic lights on routes they take regularly and set their speed to avoid stopping? Why is an app needed?

Many traffic lights are not timed. Around me my clue is the don’t walk light will flash 11 times before the signal turns yellow. In MN, they have yellow flashing lights, that start flashing, maybe 1000 ft before the signal. I love those, and they are very reliable. If the light is flashing plan on stopping as you will not make the green light you see!

There are a LOT of apps that are just plain STUPID or don’t work at all or as they claimed.

I agree Mike, this is just plain dumb. I can only imagine one car going through town in a flow of cars regulating his/her speed based upon the timing of the trafic lights, all in order to save some miniscule amount of gas.

20% my buttocks, traffic flows base upon where the drivers are going, not the traffic light timing. People making left turns, parallel parking, backing out of “heads in” parking spots, tractor trailers making turns, and a thousand other variables. The key to the best fuel mileage is as smoth a flow as possible considering all the variables. That’s also key to safety. This ap would disrupt that flow. It would also take attention away from the task of driving.

Hopefully this thing will never gain traction.