On Thursday, 17 September 2020 09:37:36 UTC+1, Martin Brown wrote:
On 17/09/2020 02:08, Fredxx wrote:
On 17/09/2020 01:32:48, tabbypurr wrote:
On Wednesday, 16 September 2020 22:46:38 UTC+1, Andy BurnsÂ* wrote:

If you travel at 60 mph instead of 70, you'll spend 16% longer time
covering a given stretch, will the NOx emission rate per mile be reduced
sufficiently to have much overall effect on the total emitted over a 4.5
mile stretch?

Fig 5 of this seems to show under a 10% factor on the NOx between the
relevant speeds

https://escholarship.org/content/qt01x9w3kf/qt01x9w3kf_noSplash_cbac2ea8aba905cf6ef7d277318129 33.pdf


It's well known that cars give better mpg at 60 than 70, so an
improvement in total NOx output can be expected.

No its not.

It might not be that well known by the general public but it is correct.
Drag goes up with the square of the windspeed and from about 50mph
onwards it becomes the dominant factor in fuel usage.

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


The people who drive with a foot hard down on one or other of brake or
accelerator are the ones who get worst possible mpg and most pollution.

They are usually to be found in the outside lane 2m behind the bumper
of another vehicle. It is reps with this behaviour that make electric
hybrids a tax dodge rather than an effective measure to save the planet.

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