Polluting Motorway Speed limit may be cut to 60mph

[theclaud]

[QUOTE 3171146, member: 45"]Maybe if you were part of this community rather than occasionally popping in and searching for petrol head threads, then people might engage with you....[/QUOTE]

I did anyway. On account of being such a big softie.

 

[albion]

Decision made, reduced limit is not going to happen - http://www.bbc.co.uk/news/uk-politics-28210416 .
....

"the Highways Agency 18 months to devise alternative methods to tackle pollution"

Translates to, 'an election is coming so a few dozen extra deaths are less important than losing votes'. Patrick McLoughlin certainly won't be blamed if Cameron loses.

I find governance strange. Can't the choking local population now sue?

 

[subaqua]

In my experience average speed cameras & very high density traffic promotes tail gating & cutting up causing overly aggressive braking. I've found that 30-50mph back road driving is actually more fuel efficient than the A14 in my Alfa due to regularly dropping off the bottom of 5th gear on the A14.

They work okay at lower traffic densities but you can get awful bunching & very dramatic speed changes if you get a perpetual lorry race going on the in nearside lanes.

the A14 from cambridge to huntingdon is far far better to drive on since the average cameras got turned on in 2007/2008 . no longer start stop from the redlight ripple caused by idiots at 60 dabbing brakes when they went past the truvelos

 

[GrasB]

the A14 from cambridge to huntingdon is far far better to drive on since the average cameras got turned on in 2007/2008 . no longer start stop from the redlight ripple caused by idiots at 60 dabbing brakes when they went past the truvelos

Strange because on the A14 I was unable to use the CC on the Alfa due to constantly changing speed between 35 & 70mph. This is what long term users of the A14 at work say as well.

 

[Bad Company]

Badders! There you are - popping up to defend the indefensible every now and again. How nice.

Why indefensible?

We were getting an 80 limit, then a 60 limit, now no change at all.

 

[theclaud]

Why indefensible?

We were getting an 80 limit, then a 60 limit, now no change at all.

It's political cowardice. The case for lowering the limit is unanswerable. You can tell this from the way they are scrabbling around looking at desperate "alternative" measures. Why do we need an alternative to a simple and workable solution?

 

[subaqua]

Strange because on the A14 I was unable to use the CC on the Alfa due to constantly changing speed between 35 & 70mph. This is what long term users of the A14 at work say as well.

when the truvelo were in it was start stop all the way from the crem to spittals interchange, not had experience going A14 towards ipswich from cambridge.I hated using the A14 for that reason. i now think it is a good road again.
the same used to happen on the A13 from beckton to dagenham until the average speed system went in and now although still heavy trafic the speed is around 20-30 and not start stop.

 

[Bad Company]

the A14 from cambridge to huntingdon is far far better to drive on since the average cameras got turned on in 2007/2008 . no longer start stop from the redlight ripple caused by idiots at 60 dabbing brakes when they went past the truvelos

I use that road often. I doubt many other regular would agree with you.

 

[Bad Company]

It's political cowardice. The case for lowering the limit is unanswerable. You can tell this from the way they are scrabbling around looking at desperate "alternative" measures. Why do we need an alternative to a simple and workable solution?

The nox increase for cars in moving between a steady speed of 70mph and 60mph is almost immeasurably small at the tailpipe.

Lorries produce much more but they are not traveling at 70mph.

 

[youngoldbloke]

There has been a 50 average speed limit on much of this stretch for a long time, J28-31 at the moment, renewing the central barrier, and forecast to continue for a long time yet. Has/is any research on omissions/noise on that stretch been done during this work?

 

[Wobblers]

The nox increase for cars in moving between a steady speed of 70mph and 60mph is almost immeasurably small at the tailpipe.

Care to supply a citation for that?

And pollution is rather more than just nitrogen oxides. In fact, there's a large and growing body of evidence implicating fine particulates as a major, perhaps the major, problem.

 

[subaqua]

I use it regularly. I agree with @subaqua

thats too good a quote to not consider using as a tag line !

 

[albion]

Apparently 2010 was the pollution safety target but now it won't happen till 2030.
http://www.theguardian.com/environment/2014/jul/10/uk-cities-breach-eu-pollution-limits-2030

It is in London, Birmingham, and Leeds where you all get to suffer the most.

 

[Bad Company]

Care to supply a citation for that?

And pollution is rather more than just nitrogen oxides. In fact, there's a large and growing body of evidence implicating fine particulates as a major, perhaps the major, problem.

Bit of a Google came up with - http://www.diaryofanadi.co.uk/?p=14616

Care to supply a citation for that?

And pollution is rather more than just nitrogen oxides. In fact, there's a large and growing body of evidence implicating fine particulates as a major, perhaps the major, problem.

The minimal increase in roadload does not significantly increase Pmax, (the engine speed is higher (because you're generally already in top gear at 60) you can make the higher power requirement from the same torque (and hence the same Pmax/BMEP). At such speeds, the exhaust after treatment system will be fully working, and the actual tailpipe Nox emissions are incredibly tiny. For a typical passenger car, 85% of tailpipe emissions occur at cold start (when the after treatment system is not yet operational.

Admitedly I 'nicked' most of that partly from another forum and partly from speaking with my son who is a vehicle design engineer at a motor manufacturer. There is more which I will try to post up later.

Also the proposal does not account for somebody driving say a Tesla which can apparently reach 130 mph with no emmissions.

 

[subaqua]

Bit of a Google came up with - http://www.diaryofanadi.co.uk/?p=14616


The minimal increase in roadload does not significantly increase Pmax, (the engine speed is higher (because you're generally already in top gear at 60) you can make the higher power requirement from the same torque (and hence the same Pmax/BMEP). At such speeds, the exhaust after treatment system will be fully working, and the actual tailpipe Nox emissions are incredibly tiny. For a typical passenger car, 85% of tailpipe emissions occur at cold start (when the after treatment system is not yet operational.

Admitedly I 'nicked' most of that partly from another forum and partly from speaking with my son who is a vehicle design engineer at a motor manufacturer. There is more which I will try to post up later.

Also the proposal does not account for somebody driving say a Tesla which can apparently reach 130 mph with no emmissions.

would be fairer to say without emissions at the point of use. there are still emissions from the method of generation, but these don't kill you if certain groups are to be beleived