There are two drawbacks to that idea. One is the cost to the consumer and the other is the cost on the nerves.

First, most of the wear and tear on an engine is when it is started. Granted, if the stop and restart cycle time is short, oil is still coating parts, but it doesn't take long before the engine looses lubrication advantages. One way is to have an electric pump prime the engine with oil on critical parts before the engine even starts to turn, however, virtulally no cars have such a system. Any fuel saved by doing stoping the engine at lights would most likely be erased with the cost of engine wear over time.

Second, if everyone turns off their car at the light, then there is a delay waiting for the cars in front of you to get started, so by the time it is your turn the light is turning red again.

Finally, a better solution (and cheaper) is to synchonize traffic lights on major roads so that the probability of having to stop at a light is much, much lower. This is a win-win because you save even more gas and you get to your destination faster and with less traffic congestion.

So, why don't cities do this? Cost. It costs money to synchronize lights and city budgets are not that rich. However, the actual cost to do this is less than the total amount of cost drivers pay in extra gas, but nobody wants to pay more taxes, so it is a lose-lose situation, but that may change.

Hi

Synchonisation of traffic lights can be expensive if you want to force the lights to follow the traffic. However an earleir system that has been tried in a number of places is to get the traffic to follow a light pattern. One early example, Slough, England, set a Town's through traffic to 30 mph so that if you travelled at 30 mph you would sail through. This worked a charm; the timing was such that if you hit a red, when it turned to green you were back on sequence. It worked brilliantly.

Obviously if you travelled too fast you would hit a red and had to stop, but, as above after the restart if you stayed at 30 mph you would sail through the rest.

Enjoy

Sleepy

Not sure where that experiment led to - I am talking about 1950!!

Think the other way. Traffic adjusts to the lights. Your speed is regulated to whatever the township wants (i.e., speed limit).

So, we agree!!

Sleepy

I like what they have in Detroit in some places. Not sure what they call it. The inside lane accesses a u-turn in the median. If you want to turn left you must u-turn, merge and then turn right. I found it quicker than waiting for a light. Especially when a light does not have an advanced left turn.

No lights therefore no stopping traffic flow.

I found round-abouts to be an even better approach. There are not very many in most parts of the US, but when I traveled in Europe there were many. I thought they were very useful and resulted in minimal delays.

I gotta tell ya, here in Arizona we are starting to install roundabouts and after seeing these people deal with a new concept - I want to put cameras up and sell the films.

I must say I agree. When I lived in Florida they put one in and some people started calling it the devils circle. I really could not understand what was so hard. I guess it was just different. When I was in Europe, you had to remember where you were so you knew who had the right of way.

Oh, the freekin' round-abouts in the UK. Totally screws up your sense of direction. You figure out which way you need to go, then then they spin you around, (in the wrong direction, as your driving on the wrong side of the road), then you come out the other side, not knowing which way is up.

We did away with rotaries year ago. Just build a bridge. Driving in circles is not a solution.

Did away with rotaries???

Hingham Rt. 3-A

Bourne, Cape Cod

Chatham, Cape Cod

Right in your own backyard in Worsta'

Cheers!!

Ouch!, BSR, you are correct! I guess they've been TALKING about getting ride of them for years. They got ride of the one at Lincoln Sq, in Wista, and I believe the one at the Sagamore bridge is gone too. There are several more I can think of here in The People's Republic. There's one at Rt. 2 and Rt 91, at the start of the Mohawk Trail. And another at Rt. 91 and, hum, let me think, perhaps Rt. 5 somewhere around Holyjoke...

The last photo is Washington Sq, at Union Station, in Wormtown.

A quick trivia question: Who's statue in at the center of Washington Sq?

This was done very effectively on 19th Ave in San Francisco. I lived on the left coast for a few years back in the mid-eighties and I remember making the trip from the Presidio to the airport fairly frequently and 19th Ave. was on that route. If you went the speed limit, you would hit maybe one red light along the route. If you went faster, you just had to stop and wait for lights to change. It worked remarkably well.

The wear on engines due to starts is generally due to cold starts. Starting a warm engine, especially an engine designed for this (which a company like Mercedes would do) is not bad. And the reduced idling time would probably reduce engine wear and increase the time between required maintenance.

I would hope that the start time and acceleration would also have been addressed. It is a basic understanding that a change like this must be seamless to the consumer or it would not make it past the first stages. Besides, whenever I'm 3 or 4 cars back from a light I always get stuck behind some 90 yr old grandma that takes the entire green just to get through the intersection anyway.

I am a fan of traffic light synching (nothing worst than driving through a fresh green and stop 10 feet later).

Synching falls apart under heaver traffic since the traffic has to go somewhere and there's always going to be little slowdowns along the way and eventually there are other kinds of bottlenecks like construction, breakdowns etc.

The other danger in synching is 'everyone cruising through' at 30mph and someone arriving at an intersection slightly too soon, expecting the light to change, and someone else sneaking through after the yellow goes red. Suddenly you're dealing with accidents which include cards moving at their full road speed and drivers expecting to just keep moving. (My sister and her husband were T-boned at an intersection where they were crossing just as it turned yellow and someone perpendicular had set their cruise control and already jumped a couple lights...arriving several seconds too soon to pass through safely).

[brainstorm]

Since lights are essentially a binary system (GO or STOP) I think the answer is in lighting and signage that allow for the adaptation of cars' speed BEFORE they arrive. For example. We've all seen the arrows above lanes saying which are open (green arrows) or closed (red X). What if these sort of signs could be connected with a system that monitors the flow rate of vehicles. In case of a lane blockage due to a stall, it could stop the immediately blocked lane, slow the adjacent lanes and speed up the lanes further away (even a bit over the normal limit), maintaining the flow rate of the original lanes full of cars going a reasonable speed with safe spacing.

I picture the routing of traffic around the obstruction like the flow of water around a square block placed in a shallow flow. The stagnation immediately in front of the block would be the Red X arrows, normal flow as single arrows and the accelerated flow around the block as something easily recognizable like double arrows?

This same model could be employed on both the local level (i.e. lanes on road) or on a larger scale (i.e. flow between the different roads if there is resistance on one).

I think the network of lights and traffic flow sensors could be deployed as independent modules where the lights contain the sensors. The algorithm for what the sign would announce be announced as a function of the base speed for the road

• Base speed for normal use,
• Base speed plus a 'lower' bias for areas adjacent to problem areas
• Base speed plus a 'higher' bias for areas a BIT further away to maintain flow rates
• Base speed for roads that are not near to a problem.

To allow for a safe 'higher bias' the base speed would have to be a touch low but many people would gladly drive a bit slower if the traffic network allowed them to keep moving along and guide them along paths of least resistance.

Local light/sensor groups would have to have a regional network connection to upload/download info about nearby roads and also a bias for environmental things like weather (big downward bias if ice/snow is involved...upward if roads are dry and warm), rush hour (upward bias on main roads with lots of lanes, lower on smaller sideroads).

A new protocol for the communication of traffic biases would be created so in-vehicle GPS units could route according to the recent flow of roads instead of the theoretical maximum with a small blacklist of roads under construction or hindered by traffic.

A lot of logistics, I know, but I can't help but think about the possibility. Just watch water in a river sometime. While the inertia of the moving water plays a global role in where the water goes and how it forms the shape of the 'infrustructure' that carries it, the small changes in the riverbed (ledges, bumps, logs, rocks etc) all have an influence on the local flows...all while not preventing the overall flow.

I think a computer simulation called for...if it had a significant impact on the amount of cars just sitting around idling in traffic then perhaps some environmental grants from the gov't would be accessible...

[/brainstorm]

Sounds like they are trying any way they can to meet the governments demand for better fuel economy. With out any consideration to the consumer. Most starters and there switches are not designed for that type of duty. Which will decrease the life of the system. Which will increase maintenance cost.

Some states in US have regulations about turning your vehicle off in traffic the restart impedes flow. Less of a chance that the vehicle will be broken down if the starter failed if the engine was left running.

They talk it up because it appears to save fuel. Won't the manufacture of all the additional parts use fuel. Won't the vehicles behind these cars burn addition fuel waiting for it to restart and get going.

What about using 'roundabouts' as used in Scotland and Ireland. They are probably used elsewhere, but these are the only ones I have experienced when vacationing there. They seemed to keep the traffic flowing nicely.

Here in South Africa , there is space in many instances where "big roundabouts" would be the cheapest and best. Unfortunately, only one town-management namely Welkom "Welcome" has only installed only these traffic-circles.

Our Provincial=Administration is still to backward to have propper insight and stil use "robots" [As traffic lights are called here] where-ever possible.

To my mind, huge traffic circles bring the speed down but the traffic keeps moving. This saves time, feul, money, air polution, vehicle-clutches, brakes, electricity, upkeep etc. If traffic is kept moving the amount of money saved would be tremendous!!!!!!!!!!!! How do one get this in their thick scull's?

I think this is a great idea. Imagine being stuck on the freeway in a sea of cars that are not running instead of spewing emissions.

But I wonder how the system would handle start-stop traffic.

Introducing something like this into real world applications is difficult. And a hard sell.

Still think it is better not to have to stop in the first place.

I don't disagree. But changing infrastructure is difficult, expensive and would cause a lot of stopped traffic during the construction.

Similar to the roundabout mentioned, ring highways work well. In Winnipeg the highway allows access all around the city without stopping.

Looking at an issue one small component at a time never seems to work. From a bigger perspective many ideas coordinated could affect fuel and energy consumption greatly. But it seems the only body in place for this is government and we all know where that leads us.

I don't know. How much effort is involved with upgrading existing traffic lights to programmable ones that are synchronized?

My guess, whatever the cost, communities look for the cheapest initial cost system and disregard long term savings.

So what are you trying to promote here? Some type of system, (that costs money), that's going to save me several drops of gas, that will pay for itself over exactly how much time. So, for the 5 seconds I'm stopped at a red light, my engine shuts down. Does the radio stop? Does the heater stop? Do my lights go out? Then, when the engine starts up again, do I have to recharge the battery? Have you accounted for the extra wear and tear on the starter, and the extra drain on my electrical system?

I don't want one. My truck is complex enough. Your grabbing at straws here. This type of system won't pay for itself in 100 years.

I think parts of Canada have been doing this for years. Maybe they rescinded that now.

Parts of Canada?!? Automotive wise we've been hangnig on to the coat tails of the 'big 3' so they'll keep their plants open in Canada. If you don't see this in the states then I HIGHLY doubt anyone is turning off their engine in Canada. There's only 3-4 months of the year you could get away with this and not need an auxiliary heater of some sort to keep from freezing or, at the very least, the windows from fogging up.

Perhaps in BC where the climate is quite different because of the mountains.

I have heard of a motor that restarts easily because at least one cylinder is already compressed and a direct injection of some fuel and a spark is all it takes to start the engine. No fancy belts, pulleys, starters or huge batteries necessary...just direct injection. A typical gas engine requires the started to be engaged to get the valves opening so fuel can get in...direct injection is more complicated but allows fuel to be misted straight into compressed air in the cylinder...add a pinch of spark and BAM! A running engine.

I think I'm still leery about the whole idea of stopping engines. I don't think I'd buy one until all the kinks with gasoline direct injection, oil starvation (since the oil pump can potentially be stopped quite a bit) and overheating (the cooling system also stops often).

One thing about recharging the battery, is yes we have to drain the electrical system but the engine is more efficient and creates less smog when it is running at operating speed compared to running at idle. Hopefully we can agree, the engine can charge the battery and use less fuel and make less pollution at moderate rpm than at idle.

The heater is based on coolant temp and will work just fine at a stoplight. The lights, heater fan, radio and other electronics will work and drain the battery. The battery will be charged later. The efficiency gain for a passenger car is said to be 4-6% with a start stop system and this is probably modeled on a city stoplight filled street. It would not save anything on country roads or long highway driving cycles.

YES, the system is setup to save several drops of gas. Their are not a lot of giant gains in fuel economy ready to go. This is an incremental step toward better fuel ecomony. Your right it is not free and it will have a terribly long payback. The push for this technology is coming from Washington D.C. and not people buying cars. The new cafe requirements require 35mpg for the whole fleet by 2020 (current average is about 26mpg). New pollution standards require less pollution so turning off the engine is a simple way of saving a few puffs of smoke to help incrementally get under the requirements. Until we get another giant discovery to uncover more fuel efficient, less polluting, and cheap engines this is what we have to live with. It is labeled progress and thanks to Washington WE all have to pay for it.

I like it. It makes use of old technology (starter/generator) to simplify design and improves it.

On a smaller vehicle I see no issues with the generator driving the car and creating the compression in the engine for starts. It works now if you leave a standard transmission in gear. (I ran out of gas)

Batteries will be more expensive when you have to replace them but they will probably be a better battery than the crappy ones in cars now. They will have to be to handle the loads and discharges. And hopefully live longer. And if a battery like this becomes main stream then we can all build an EV because the batteries will be cheap.

I disagree that heat should go electric. ICE's produce so much waste heat anyways it is foolish to use motive power to create heat via resistive elements for cabin comfort.

As for A/C, adding an electric motor and it's drive electronics also appears foolish given the readily available and efficient power from the ICE that's already running. The drive losses on a serpentine belt is about 5%. An expensive 3p BLDC or PMSM with the requisite inverter will at best get you 80% efficiency especially when you figure in the efficiency losses of the alternator-rectifier, then the charge-discharge cycle of the battery, and the efficiency loss of the inverter and then the efficiency loss of the compressor motor. A typical A/C compressor will consume about 1.5kW of power or about 2 hp. That would require about 1.9kW of input power to get the cooling.

Now from an emotional standpoint, some may want to pay the premium in both purchase cost and efficiency to make a statement. To each his own. For me and my driving profile, a hybrid does not make sense or cents.

I'm not saying that we shouldn't have start-stop systems. It's just that if you want comfort, it's better to leave the engine running. Perhaps if you spent most of your driving in stop-and-go city traffic, it might work. But for most of us, it's just not there yet. It will be interesting to see if the engines in start-stop systems exhibit shorter bearing life as the years rack up. I'd say in about 10 years we will see. Does anyone know if these systems use an auxiliary oil pump to keep the bearings lubed?

Of the start-stop systems, I tend to prefer the start-stop system that uses the flywheel as a rotor with embedded permanent magnets and the coils in the flywheel housing. That is a set-up that can generate prodigious amounts of torque, has no belts or drives to break or wear out and fits nicely with existing technologies and tooling. This system may eliminate a part by combining the starter and alternator into one, BUT it adds a complex, high-power four-quadrant converter/inverter to the system. That will be a reliability issue.

In the broad spectrum of things, for the city commuter an electric with a plug at both ends is not a bad short-term solution.

And the social solution *car sharing* is damned clever.

And there is always Budget when you have to go out of town.

Aw Bricktop

If you think your truck is complex you should see the headlight switch sequence for the wife's Grand Vitara (Suzuki).

A bloody matrix in the the owners manual

I'll post tomorrow - just amazing

Okay like everything else this is a good idea if they have all their homework done right. European car manufacturers (Audi definitely has) have been dealing with direct injection since the 1990's, and honestly I don't know a whole lot about the system but if the simple injection of fuel and spark in an already compressed chamber starts the engine or at least could, heck do it. I love german engineered vehicles, but thats just a personal preference.

As for the whole stop light sequencing that was mentioned earlier. My old roommate is a civil engineer for MODOT in St. Louis, the BS traffic lights that are out of sync are a pain to all everyday drivers. Some lights use pressure sensors in the road to change on account of vehicles present, but during the day in heavy traffic, I hate these, always a mess and because they don't care to have a civil engineer to change it or they don't want to invest in a similar system for this. My old roommate has done a lot of time studies on certain main streets in St. Louis and they use that data to keep the traffic lights in sync, if possible. Now back home, you could drive 35 through Charleston and hit every light green, well when they installed two new lights, good luck, always hit a red at least once, unless you drive at variable speeds after each light.

But what I want to know is, whats the use shutting a vehicle off for a few seconds, let alone a minute, you burn more fuel at start up than at idle, unless you have a very big and thursty V-8, 10, or 12. But with the whole direct injection deal, that might not be the case.

Even today I can drive Colorado Blvd in Denver from one end of the city to the other, a separate sign tells you what speed the lights are timed for. Never got much farther.

But I can tell you from an interview in the local paper for Mesa Arizona - the traffic manager said they mis-time the lights to slow traffic down for the high preponderance of elderly drivers.

At a railroad/railway crossing it makes a lot of sense. At a signal controlled traffic intersection it makes no sense at at...and portends a significant traffic hazard!

The fallacy comes in that the adherent of the stop-start advise will be perceived to be only that person (in which case...one person killing and starting their engine would not have noticeable effect on other vehicles or traffic.) But when it is perceived that each and every driver would be "one person killing and starting...", Then one must take into account what happens when a host of vehicles, each pursuing its own aim and each attempting to respond rapidly and dynamically to traffic signals, finds itself (collectively) in various states of (un- or poorly coordinated) vehicle operabliity and non-operability at the same time.

Then there's also the fact that, in many jurisdictions (and barring unusual circumstances such as gridlock), it would be a cit-able offense to voluntarily disable a vehicle at an intersection; that is, it is typically prohibited to stop a vehicle in a moving lane of traffic. (At a train crossing, a lane of traffic would be deemed to be blocked; hence not a moving traffic land. A traffic lane controlled by a signal would not be deemed a blocked lane but, rather, a moving traffic lane.)