Impact of London's ULEZ expansion on air quality

[dan_b]

https://www.standard.co.uk/news/transpo ... 59317.html

It works! The expansion of the Ultra Low Emissions Zone to encompass all of London inside the North and South Circular ring roads has reduced the number of diesel vehicles in the zone by 60%. PM2.5s and CO2 levels are down too

[richbee]

https://www.standard.co.uk/news/transpo ... 59317.html

It works! The expansion of the Ultra Low Emissions Zone to encompass all of London inside the North and South Circular ring roads has reduced the number of diesel vehicles in the zone by 60%. PM2.5s and CO2 levels are down too

Surely the only thing that matters is the reduction in the Nox PM2.5 levels - the number of diesel vehicles is irrelevant, as there could be the same number of cleaner Euro 6 / 6.2 diesel vehicles, and have the same effect on the Nox PM2.5 emissions.
I wonder in general what the effect is of pushing out new diesel vehicles in favour of petrol, which emit more CO2, from a climate change point of view? Obviously as we change to more EVs, the effect should be much better, but as a short term measure, I wonder if 'dieselgate' has been counter productive for climate change - although positive from a local air quality point of view?

[spread-tee]

It is both PM2.5s and NOx levels that count, for instance our car is way cleaner than the limit for PM2.5s but above the limit for NOx so it wont be compliant.

ho hum......

Desp

[marshman]

CO2 emissions matter for climate change - PM2.5 (particulate pollution) and NOx matter for air quality. The two often get conflated when it comes to discussions on "clean air zones". Remember the whole shift to diesels was on the basis they emit less CO2 and thus better (or more correctly less worse) for the climate.

Given the introduction of the Hybrid Black Cab and the number of buses in Central London that are also Hybrids and now some fully electric, it is no wonder the numbers are falling and probably impossible to attribute any of the changes to the introduction/expansion of the ULEZ - its just a revenue raiser IMHO, and a short term one at that.

[dan_b]

Important not to get drawn into "either/or" debates and the concern about the perfect getting in the way of the just doing something.

Yes a major source of NOx/PM2.5s within all cities is public transport infrastructure - ie. buses and taxis. And yes the ULEZ doesn't cover those. But other legislation/ policy levers has started to move in that direction. There are certainly a lot more BEV buses on the streets of London (Not H2) and likewise the change in legislation around zero-emission taxis. The recent availability and therefore adoption of EV vans for last-mile delivery will also help here.

However, it is also the case that personally owned passenger diesel vehicles are also a big problem from a NOx/PM2.5 point of view, and so this is a policy lever designed to change the direction of travel with those too. So I'm of the opinion that it's a good scheme and more than just a revenue raising exercise.

[Mart]

Dan ... yep.

In fact, looking at the 'small' number of vehicles that don't comply, and the scrappage scheme being offerred, I don't get the impression that this will raise all that much money, v's the effort of operating it. Anything that raises the issue of air pollution in our cities will help to drive change as it makes folk think more about what they buy (or don't), and how they act.

Probably getting ahead of my ski's a bit, but I suspect that by 2025(ish) all of the positives regarding BEV's, will be well accepted, combined with some reduction in prices, and an expanding secondhand market, helping to bring about large scale ......... damn can't think of the word (covid brain fog) ..... acceptance isn't quite the right term, but folk nolonger fearing the change, but starting to embrace it. I really do think we are close to that tipping point, just need lower costs, and expansion of home and rapid charging for those without driveways nor guaranteed spaces.