Motorway NOx

If you'd trust a mesh network of connected controllers, plus a very controlled environment, it could just work.

"It definitely will work with absolutely no possibility of failure. With a £10,000,000" life insurance policy thrown in for free" might sound a bit better.

michael adams

...

Sorry I misread the text. You are correct, one would reasonable expect a harder working engine and hence hotter combustion would have a higher overall NOx in the exhaust.

At cruise speeds Nox/mile will be (inversely) proportional to MPG. Over a fairly broad range of speeds. Its stop start that wastses fuel and increases Nox, so get rid of traffic lights and speed limits...

Also its by no means correct to say that the better MPG (and lower NOx/mile) will result from lower speeds anyway. A big engine turning very slowly is not necessarily at its most efficient. My car reached optimum mpg between 50 and 60 mph and is still up there at 70. What kills that is having to put on the brakes....and then get it up to speed again.

It's more knee jerk reactions based on 'intuition' than scientific analysis based on data.

I saw somewhere that a lorry at a certain distance behind another one could reduce fuel but increase it for the leading lorry. I guess that it stops the air flowing into the gap thus maintaining a higher differential pressure for the leader.

The M6 is fine north of Lancaster and after the border when it becomes the M74 almost up to the central belt of Scotland. It's noticeable how the restrictions on road works changes as you go north. Down near Manchester, its miles of warning signage, average speed cameras and concrete barriers between the live lanes and workers. Bit further up some advance warning "roadworks 3 milles", 50 limit, standard cameras, and cones. Further north "roadwaorks" sign at 400 yds before the cones start to close the live lane.

They had the gantry signs saying "60MPH limit in force to lower pollution" (or similar) last year on the M1 in South Yorkshire.

I also notice that every now and again the gantry signs where the speed cameras are located have the national speed limit sign showing. I was once told that this meant the cameras were operating at a 86MPH speed limit and so I have reduced my speed to 86MPH when passing them.

The cameras have flashed me 3 times this year when no NSL sign is showing and I have had no NIPs.

yes, I think it cleared around there, I was only going up to Grange-over-Sands, so as the roadworks ended the sun came out and the scenery improved ...

In message <rjv7s7$2af$ snipped-for-privacy@dont-email.me, michael adams snipped-for-privacy@ukonline.co.uk> writes

I must bring that into consideration next time I am being harried in an outside lane.

Or me if the lane to left is clear of the knob on the outside lane. They have 5 seconds to move over or I undertake.

well if they go slower and not 80 or 90 it will help

NOx is going to vary a great deal depending on the type of engine and condition of it.

CO2 output does tend to be largely speed dependant. Same as MPG.

making up more silly bs I see

FWIW it's been well known for a long time.

ICBW but AIUI the total cycle of electric versus diesel does not show a convincing 'green' benefit to electric. It does move the pollution away from residential areas to power stations, but that does not achieve 'saving the planet' however the greens choose to define that.

NT

Cyclists sometimes discover just how effective that trick is. They tend to then discover that nothing about pedal bikes is really upto the sort of speeds trucks do.

NT

If you?d driven into Glasgow yesterday and seen the yellow pall of smog hanging over the city you might think otherwise.

Volvo/Polestar are trying to put some figures to it all (which account for carbon costs of build & use).

Any genuine comparison is fairly complex, involving a bunch of debateable figures. The error margin gets too large.

NT

So your assertion is equally debatable...

Tim