Is a Progress Bar on a Traffic Light a Good Idea?

They already have traffic lights and padestrian crossings in Manila with timers on them. As far as I can tell they don't really help there.

Pedestrian crossings with timers exist in Singapore. They are tremendously helpful for 2 reasons :
a) To help pedestrians judge if they can make it across
b) To alleviate the impatience of anyone waiting.

Sometimes all we need is to know how long more something will take to alleviate our impatience. We don't always need it to be faster.

Nooo. In racing, there are these things called light trees. Even being 24 myself, that is essentially what you're going to give to all of these young "adults" who want to destroy their car from stop light to stop light thus increasing traffic hazards. Our country will never shut off our cars for long enough or in a large enough number while only waiting for a red light to make this risk worth it. The footprint decrease would be miniscule at best. Fail DOT.

It's not a great idea to shut off the engine of a car all the time. The crankshaft is supported by a journal bearing, which relies on a thin layer of lubricant to support it. When you start the engine, there is no lubricant and momentarily there is metal on metal contact. When engineers design the crankshaft and bearings, they allow a certain amount of wear based on how often they expect the engine to be started. So they'll specify 10 000 starts over the life of the car or whatever.

Starting and shutting your engine all the time will reduce the lifespan of it.

I should add, some cars like the new Mini have been specifically design to shut off and start repeatedly. Then it is not a problem.

This is not the case with most cars.

Same with Delhi/Mumbai. Many major traffic lights have countdown timers. In a way it does help as the motorists can turn off their vehicles when the waiting time is large.
However, the last 5 seconds before the light turns green resemble the start of a NASCAR race :)

Meh, ok idea I guess. Around here the cross signals basically perform this function as most of them now count down. Even before that the flashing crosswalk signal was a pretty good way to judge how much time you had left on your red.

It's a horrible idea at all to shut off your car for a red light

One of the first things I was taught as a driver was that shutting off & turning on the engine was a waste of fuel; even if you're idling for a short span, you use less fuel than you would if you started the engine.

Otherwise it's a good idea for the sociological factor. I appreciate the crosswalk countdowns I see here, as they're also like a communication to drivers that they can turn right soon.

In India, some lights are like this. They have a number countdown. By 8, engines are revving. By 4 or 5, everyone takes off ;)

But, I don't think it's such a bad thing, because I think that it's not necessarily bad to run red lights.

Eh, sounds like an interesting idea. It sure would come in handy w/ a few of the intersections here where the light seems to take FOREVER to change.

buddhaflow, I hope you're trying to make some "over population" joke. if not, you need a swift kick to the teeth. especially with a name like BUDDHAflow and sayin that. lol

and Johnny cat, it depends on the year, make, and model of car.
Cars that are cold have a computer that increases the air fuel ratio,rpms, and timing of the valves and spark plugs. but once it warms up, it goes back to normal. THAT uses more gas. same with a lot of older carburetor cars. they pump a little ''extra" fuel into the throttle body to give it a little extra "oomph" to get it started.
Most new cars, that are AT normal operating temps would not use any more gas than if they were running the whole time. and as far as the Morzs' comment, I agree, kinda. viscosity, and the capillary effect would keep enough oil on the crank I think. but I know what you are getting at.
I dunno about that argument really. I think I'd forget, and be holding up traffic while starting my car again. lol
But I do agree that it would make our roads even more dangerous by essentially turning it into a drag strip.

In Europe the amber middle light briefly comes on before the light turns green. This gives drivers opportunity to put their manual transmission cars in gear or power up again, as required. A much simpler solution.

we have timers on out crossing lights in tallinn. and it helps loads. as someone already put it:

a) To help pedestrians judge if they can make it across
b) To alleviate the impatience of anyone waiting.

As others have already mentioned, countdown timers are common on traffic lights in heaps of countries already. I can add Thailand and China to the list. ;)

I think the biggest benefits are that people don't rush to make a light (if it's visible and near zero) and pedestrians can gauge whether they can cross 6 lanes of traffic within the limited time period.

People don't turn off their engines at stop lights. They wouldn't do it if they had a timer, either.

I swear, Americans always go for the complicated approach to something so simple.

Do like Mexico and remove the yellow light from all traffic lights. Then just flash the red or green when they are about to change.

Probably save about a billion watts a year.

is it a neat idea?
yes.

Do I want my tax dollars to pay for it?
not particularly.

I live in Baltimore, and I think I'd rather see my dollars go to fixing the bloody roads downtown than fiddling with the traffic lights...

Don't know if it would be useful here in the UK. I live in a city and drive daily, what I see is a lot of drivers setting off just before the lights change to green, as they are watching the other set of lights change from green to red. This causes a lot of near misses as the last car passes the junction.

I am guessing it would only increase the amount of people setting off in the last few seconds before the change.

Several cities in Brazil already have traffic lights that indicate how long until the green lights.

Turning the engine on and off all the time is a terrible thing. It actually consumes more fuel is the car is to be left off for less than45 seconds. Besides, starting the engine puts a lot of load in several components, because static friction is a lot higher than dynamic friction.

The chances of engine failure when the car is being turned on is much higher than when the engine is already on. Thus, if people is to turn off and on their engines at traffic lights, what we'll see is a lot of people with broken engines at stop lights.

I do, however, like the idea, because I can relax for a few seconds, knowing exactly when I'll have to be in the "ready state" for the green light.

some trafic lights here in thenetherlands either have a cound down bar or a number that shows the seconds. As far as i know there not there for turning engines off and save feul, but to reduce the number of (bikes mostly) people that run te red lights. Its kinda silly to run a red light if you only have to wait 10 seconds :P

I live in the South. Here I think drivers watch the person in front of him, not the light. It's not uncommon to wait several seconds after the light changes before the cars proceed. Not sure this would help. Folks here are still confused about the right turn on a red light being OK!

Anyone else feel like they're just trying to sell us a pile of crap by claiming it would save the environment? Yes, a timer will relieve anxiety, but lets just leave it at that. Isn't it a worthy cause? Must we also claim people can turn off their engines too? That is just a BS claim that they are using to get the funding. Really, how long are the traffic lights that you're sitting in front of? Idling at stop lights isn't even the issue. It is idling in bumper to bumper traffic, and the truck drivers who need to keep their cabins on for heat. They idle for 8 hours, not 30 seconds.

I would love some kind of contraption for yellow box junctions!

I would say 90% of the drivers here in the UK do not know what they are for. Be great if the actual yellow lines burned the wheels of those obstructing others.

How about using roundabouts or rotaries? For certain traffic flow rates, they can be quite efficient. Adds a little excitement to the drive as well. :)

Oh wow, everything is SO new..... a half-century ago in the little towns throughout the midwest we still had ancient single-light traffic lights that would, during the last 10-15 seconds, slowly change from green to red and vice-versa.

Nothing new, kiddies....

Here in Pittsburgh, some pedestrian crossings have timers, and I find it really helpful. I'd imagine that timers on traffic lights would be similarly helpful.

Going from Canada to U.S. border, there's a new stoplight installed. Sometimes the wait is around 15min-30min telling everyone behind that line to shut off their engines.

Useful.

In Boston we have what they call delayed green. This means that people who get a red as they are approaching know the others won't get a green for a few seconds so it is still okay to speed through. If the people getting the green knew the green was coming they would probably go early knowing they had a few seconds after the red. I guess the pedestrians would just have to wait for the dust to clear before proceeding.

Yep, I can just see it now. The one stopped is revving to go and will hit the gas the microsecond allowed. The one coming the opposite way is thinking, "one more bar...I can make it" Collisions ensue.

Not something new. Here in Brazil i know of at least one city with a 5 stage red and green lights, with time countdown for pedestrians.

The risk/benefit of turning off a car's engine at a stoplight was discussed by Tom and Ray in a Car Talk column five years ago -

http://www.cartalk.com/content/columns/Archive/2004/June/04.html

why not get rid of all petrol cars and make electric cars the only thing allowed on the road. ?

if the law is made it will happen, just like seat belts, air bags etc.

We dont need this in NYC.. already have it, it's called watch the lights change on the perpendicular street. If you cant see the overhanging lights because of a bad angle then watch the pedestrian crossing lights. When the orange hand starts blinking "get ready". When it stops blinking "get set". +/-7 seconds later, "go"!

PLUS, combined with people running yellow lights, people jumping the gun on this timer lite will lead to alot of "no-fault" accidents.

iwashere - because electric cars are not the best choice for many people. For instance, with our cars now, I can make it to my parents in 6.5 hours or my in-laws in 4.5 hours (due to distance, not traffic). If I had to use an electric car, these day-long trips would take an extra day or two as I would have to stop for many hours to recharge the batteries at least once or twice.

Hybrids might work better, but most of them are too small.

iwashere : where does your electricity come from : oil power plants? :p :)

as for the red timer : great thing for drag racing!!!

Why not create something that will really save gas!!!??? Timed stoplights are stupid. How about smart-stop-lights??? Something that has an eye and can see down the road and change if there are no cars coming from the cross sectioned streets. How much gas is really wasted during non-busy times with timed stoplights when you have to stop for absolutely NO reason???

we don't have these where I live but if you're at an intersection with walk lights it's easy to see when the light's about to change--when the don't walk sign is blinking

They have walk light timers pretty much all over the Canadian city that i live in. You can read the time remaining from about a block away and I use them to gauge whether or not I'll be able to make the light or if I should slow down and be ready to stop. It also makes waiting for the light to change a little less irritating, I think.

In some german Cities as Hamburg, Düsseldorf and Bochum you can find such trafficlights :

http://de.wikipedia.org/w/index.php?title=Datei:Hh-ampel.jpg&filetimestamp=20060709105731