Stop-Start Technology on Buses

[DD12]

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Bus Manufacturer News & Discussion

I'm sure a thread like this was created before, however i had a look and can no longer find it. The purpose of this thread is to post news and updates regarding bus manufacturers based in the UK such as ADL, Optare and Wright. Builders like Mellor Coachcraft who do the minibus van bodies are...

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Could anyone update me please, about STOP-START engines (and transmissions) for buses ?

For a very long time, I have not seen any references anywhere, to this technology, -- has it been abandoned due to the move towards electric and hydrogen-electric buses ?? ( - Also, I haven't seen any mention of it for new cars either).

 

[Jordan Adam]

Could anyone update me please, about STOP-START engines (and transmissions) for buses ?

For a very long time, I have not seen any references anywhere, to this technology, -- has it been abandoned due to the move towards electric and hydrogen-electric buses ?? ( - Also, I haven't seen any mention of it for new cars either).

Sorry if this has been discussed before, - please redirect me if it has ( - thanks).

Moderators:- Please do not delete this question, - please move it or start a new thread if necessary ( - thanks).

Most new buses have stop-start systems, although they're not that good imo.

 

[Goldfish62]

Could anyone update me please, about STOP-START engines (and transmissions) for buses ?

For a very long time, I have not seen any references anywhere, to this technology, -- has it been abandoned due to the move towards electric and hydrogen-electric buses ?? ( - Also, I haven't seen any mention of it for new cars either).

Sorry if this has been discussed before, - please redirect me if it has ( - thanks).

Moderators:- Please do not delete this question, - please move it or start a new thread if necessary ( - thanks).

ADL offer stop/start as part of their Smartpack option for diesel buses.

 

[507021]

Could anyone update me please, about STOP-START engines (and transmissions) for buses ?

For a very long time, I have not seen any references anywhere, to this technology, -- has it been abandoned due to the move towards electric and hydrogen-electric buses ?? ( - Also, I haven't seen any mention of it for new cars either).

Sorry if this has been discussed before, - please redirect me if it has ( - thanks).

Moderators:- Please do not delete this question, - please move it or start a new thread if necessary ( - thanks).

Stop-start isn't brilliant. A batch of Enviro400s featuring this technology was bought for Arriva Merseyside's route 55 in 2017, but it was very quickly found they were struggling to keep to time because of the stop-start. It wasn't long after this when Bootle depot redeployed them onto more suitable routes.

 

[DD12]

Thanks everyone !!

I have one or two things in mind about this topic, and inter-linking stuff, like --

- Are the emissions from the latest Euro6 engines, still too harmful, - and what percentage of the worst concentrations of harmful atmospheric toxins would buses create if all buses were the latest Euro 6 spec ? ( - Stop-Start ?)

- In the latest edition of Route One magazine there is an article about dual dosing of Ad-Blue, and it's possible contribution to an even cleaner Euro 7 spec. ( - stop-start?)

I very much admire all the development in diesel engines in the last 20 years or so, and I like the "magic" that allows them to power a low-floor double-decker without taking away too many downstairs seats !!

 

[Snow1964]

I think start-stop is offered as an option.
There are various disadvantages, principally delay, and bit of jerkiness on a quick pull away.

There is now an alternative fuel saving, mini (or micro) hybrid. Basically it uses energy which would be wasted when slowing to charge batteries to run the auxiliaries (fans, lights etc) rather than use the engine to power them. Unlike a full hybrid cannot be used to move the bus without engine on.

Although Diesel engines have developed, there are now questions about if they actually meet euroVI when poorly serviced and filters are a bit clogged. There are many tales of buses in de-rate or limp mode (which means they aren’t running cleanly). The vehicle inspectorate is very poor (overstretched and understaffed) at enforcing roadside emissions checks.

 

[DD12]

I think start-stop is offered as an option.
There are various disadvantages, principally delay, and bit of jerkiness on a quick pull away.

There is now an alternative fuel saving, mini (or micro) hybrid. Basically it uses energy which would be wasted when slowing to charge batteries to run the auxiliaries (fans, lights etc) rather than use the engine to power them. Unlike a full hybrid cannot be used to move the bus without engine on.

Although Diesel engines have developed, there are now questions about if they actually meet euroVI when poorly serviced and filters are a bit clogged. There are many tales of buses in de-rate or limp mode (which means they aren’t running cleanly). The vehicle inspectorate is very poor (overstretched and understaffed) at enforcing roadside emissions checks.

That's very interesting, thanks Snow1964.

 

[py_megapixel]

I was on an Enviro 200 MMC yesterday and the engine seemed to stop running a number of times when the bus was stopped.
Are these vehicles fitted with some kind of technology which automatically turns off the engine when not moving (in cars it's usually called stop/start technology), or was the driver manually doing it? Whichever it was it seemed a bit over-the-top; it was stopping even for pauses of just a few seconds to drop off a single passenger!

Surely it can't be good for the battery to do this - and it's certainly slightly annoying as a passenger as usually the MMCs are pretty good at idling without juddering the whole bus (more than can be said for the older Enviros or an Optare for example!) but with this you get the judder as the engine starts every time you leave a stop.

 

[L401CJF]

It's stop start technology, a right slow system it is too! I drove the demo stop start E400 MMC at Stagecoach Wirral when it was on loan. Got to a set of lights and cut out, went to pull off and wouldn't restart! Had to do a full reset at a busy junction!!

 

[GaryMcEwan]

Yeah they do have Stop/Start technology for fuel efficiency.

Not entirely sure if the driver can override it and turn it off though.

 

[hexagon789]

I was on an Enviro 200 MMC yesterday and the engine seemed to stop running a number of times when the bus was stopped.
Are these vehicles fitted with some kind of technology which automatically turns off the engine when not moving (in cars it's usually called stop/start technology), or was the driver manually doing it? Whichever it was it seemed a bit over-the-top; it was stopping even for pauses of just a few seconds to drop off a single passenger!

Surely it can't be good for the battery to do this - and it's certainly slightly annoying as a passenger as usually the MMCs are pretty good at idling without juddering the whole bus (more than can be said for the older Enviros or an Optare for example!) but with this you get the judder as the engine starts every time you leave a stop.

Sounds like the system used on the newer buses used on First Glasgow no. 38. The engine cuts out for stupidly short times sometimes when boarding/alighting passengers. Weirdly it never seems to stop when in traffic held at red lights when it could actually be stopped for about 90 seconds sometimes rather than about 9!

 

[GaryMcEwan]

Sounds like the system used on the newer buses used on First Glasgow no. 38. The engine cuts out for stupidly short times sometimes when boarding/alighting passengers. Weirdly it never seems to stop when in traffic held at red lights when it could actually be stopped for about 90 seconds sometimes rather than about 9!

I think it's set up for the engine to stop when the doors are opened and vice versa.

 

[hexagon789]

I think it's set up for the engine to stop when the doors are opened and vice versa.

If that is indeed the case, that seems rather stupid. Surely being linked to the station brake would make more sense? Then it would be off when stopped at traffic lights (which is generally for a much longer duration) as well as bus stops.

 

[Robertj21a]

I think it's set up for the engine to stop when the doors are opened and vice versa.

Yes, should only happen when doors open. Many drivers know how to avoid it happening.

 

[cnjb8]

I'm sure ADL put out some thing about stop start technology saving some number tonnes of CO2.

 

[kez19]

I noticed that if it’s in park ie driver stepped off for a breather it switches itself back on (supposedly there is a way to switch that off?)

Xplore Dundee are the same, sometimes the stop/start will switch off at some stops but not at others.

 

[Bletchleyite]

Most new buses have stop-start systems, although they're not that good imo.

Arriva MK's newer buses have it, it appears just to be connected to the handbrake.

 

[geoffk]

Stagecoach buses in Exeter stop their engines when the doors open at most stops, maybe not all stops or all types of bus but I'll check next time!

 

[Bletchleyite]

If that is indeed the case, that seems rather stupid. Surely being linked to the station brake would make more sense? Then it would be off when stopped at traffic lights (which is generally for a much longer duration) as well as bus stops.

Does seem to be the handbrake on the Arriva MK Sapphire vehicles (I forget what they are), it stops before the door is opened.

It restarting when on layover could be because of the battery voltage dropping? On my car the battery is a bit borderline (but not yet worth replacing) so it only stays stopped for about 30 seconds or so so as not to run the battery down.

 

[whoosh]

Surely it can't be good for the battery to do this....

My old car:
Scrapped at 14 years old, still with the original factory fitted battery.

My current car:
Stop/start technology, original battery needed replacing at four years old.


I wonder if the stop/start technology offsets the pollution of having a new battery made, and delivered to a shop, and me fetch it. I bet it doesn't.

 

[Bluebirdscot66]

Yes, should only happen when doors open. Many drivers know how to avoid it happening.

By putting hazards on

 

[christopher]

On the MMCs there's a switch to change it to either be when the doors are open or whenever the handbrake is applied.

 

[Jordan Adam]

Arriva MK's newer buses have it, it appears just to be connected to the handbrake.

It depends when built, earlier examples have it connected to the handbrake, but later they changed it to the doors due to issues with buses cutting off at junctions right as they needed to set off.

 

[Applepie356]

Stagecoach London have E400MMC Smart hybrids, can’t say the stop start is very effective though.

In the early months it would activate when the handbrake is pulled, then they changed it so it only activates when the front doors are opened.

I guess part of the reason for that change is the ESS cocking up every now and then and not restarting the engine when it’s supposed to, forcing drivers to restart the bus.

The engine only stops when the front doors are open, so unless lots of passengers are boarding the engine is stopped for like 5s. Also now that the buses are 2-3yrs old they stop-start a lot less frequently and some even restart the engine like 1s after stopping. I’d be surprised if the ESS system contributes to less emissions on buses as it seems more like a gimmick.

 

[DD12]

My old car:
Scrapped at 14 years old, still with the original factory fitted battery.

My current car:
Stop/start technology, original battery needed replacing at four years old.


I wonder if the stop/start technology offsets the pollution of having a new battery made, and delivered to a shop, and me fetch it. I bet it doesn't.

Thanks for that, whoosh -- I agree, -- a whole-life assessment and passport (etc) for pollution and costs seems to be needed !

 

[hexagon789]

The engine only stops when the front doors are open, so unless lots of passengers are boarding the engine is stopped for like 5s. Also now that the buses are 2-3yrs old they stop-start a lot less frequently and some even restart the engine like 1s after stopping. I’d be surprised if the ESS system contributes to less emissions on buses as it seems more like a gimmick.

I definitely seems more of a gimmick, I would really love to see how much fuel (if any) it saves after the buses have 'worn in' a bit

 

[Gloster]

Southern Vectis’ new buses have software that immediately switches off the engine if the door is opened or the bus knelt when the handbrake is on. All well and good, but sometimes when people are getting off the engine has to be restarted after only a few seconds (less than five at times). Is this really as environmentally friendly as it is claimed? And what about the wear and tear on the engine and starter-motor? (Note: I am strongly in favour of anything that will help the environment, but get annoyed by things that are more to give an image of being environmentally friendly than actually doing anything.)

 

[Eyersey468]

Southern Vectis’ new buses have software that immediately switches off the engine if the door is opened or the bus knelt when the handbrake is on. All well and good, but sometimes when people are getting off the engine has to be restarted after only a few seconds (less than five at times). Is this really as environmentally friendly as it is claimed? And what about the wear and tear on the engine and starter-motor? (Note: I am strongly in favour of anything that will help the environment, but get annoyed by things that are more to give an image of being environmentally friendly than actually doing anything.)

It will be the stop start thing that a lot of modern buses have now, I'm unconvinced that it really does save any fuel if its restarted after only a few seconds

 

[Trainman40083]

Southern Vectis’ new buses have software that immediately switches off the engine if the door is opened or the bus knelt when the handbrake is on. All well and good, but sometimes when people are getting off the engine has to be restarted after only a few seconds (less than five at times). Is this really as environmentally friendly as it is claimed? And what about the wear and tear on the engine and starter-motor? (Note: I am strongly in favour of anything that will help the environment, but get annoyed by things that are more to give an image of being environmentally friendly than actually doing anything.)

Where I live, we refer to "stop start" buses, as "stop, stop, it's died buses "..

 

[90019]

My old car:
Scrapped at 14 years old, still with the original factory fitted battery.

My current car:
Stop/start technology, original battery needed replacing at four years old.


I wonder if the stop/start technology offsets the pollution of having a new battery made, and delivered to a shop, and me fetch it. I bet it doesn't.

On the other hand, my current car with stop start is 9 years old and has it's original battery with no signs of needing replacement any time soon, while my previous car without stop start needed a new battery at 6 years old.

I would think it's a lot more down to the usage profile of the car than just whether it has stop start.

Which, taking it back to buses, presumably it works fine on routes with longer stretches of running out of town where there's enough time running to sufficiently charge the batteries, but on purely urban routes with lots of stopping and starting, it'll presumably wear the batteries out faster as they'll rarely be running long enough to fully charge the batteries.

It's not quite the same as they're hybrids and can pull away on battery only, but when Lothian first got the 7900s it was quite common for the engine to turn off at most stops at the beginning of the route, but only infrequently as you got further on as the distances between stops wasn't enough to get much charge into the batteries. Though it did work much better when heading from Clermiston to Easter Road on the 1 (as they were allocated to) as it was overall downhill with a few decent hills that you could used to get some charge in the batteries.