ULEZ expansion. Who will be affected?

The Mayor of London’s plan to extend London’s Ultra-Low Emissions Zone (ULEZ) to Outer London is causing great consternation but having looked at the criteria by which vehicles will be charged it seemed to me like the objections are over stating the real impact. Especially after I discovered that our 19 year old Ford Focus will be exempt.

So I wanted to try and understand the impact these proposals would have on car owners in London. To do that I needed to be able to:

• count vehicles registered to households according to their London Borough
• categorise them according to their fuel
• group them according to the year they were registered

This would mean I could count all the privately owned cars in Inner London (old ULEZ) and all the privately owned cars in Outer London (new ULEZ), break them down according to whether they were petrol or diesel, and through their year of registration infer whether or not they were exempt from the charge or not.

Make Things Open, It Makes Them Better

The Department for Transport (DfT) publishes a lot of brilliant data on GOV.UK but while one dataset (df_VEH0220) offers a breakdown of fuel types and another dataset (df_VEH0124) provides the year of registration for each model, cross-referencing those would take a long time. And even then, I wouldn’t have the breakdown by local authority.

Amazingly the DfT provides an email address straight to the vehicle statistics team. And even more amazingly when I explained what I was trying to do they replied with the data I needed (including a follow up revision to make it even easier to work with). Thank you Stephen!

Now I can establish a baseline dataset of ULEZ compliance as at March 2022 within these parameters:

• only privately owned cars (so not company cars and not goods vehicles, vans, etc)
• focusing on diesel and petrol (the non-compliant and not the story of any shift to electric)
• assuming 2005 for petrol and 2014 for diesel are the cut-off years, even though I know this marks cars (like ours) that are exempt as chargeable.
• I’m ignoring the 2021 extension of ULEZ to the boundaries of the North and South Circulars to make it easier to do a simple comparison between Inner and Outer is cleaner and easier for everyone. This understates how many households currently pay ULEZ and overstates the future impact on Outer London households.

Overall picture if ULEZ was in force across London in March 2022

There are almost 2.5m private cars in London and 1 in 4.5 (22.5%) of them would have to pay the ULEZ charge if it had been in force for the whole city in March 2022.

A similar number of petrol (280k) and diesel (271k) cars are affected. However, because there are so many more petrol cars on the streets, the proportion of affected petrol car owners is much smaller with 17.5% of petrol cars needing to pay a whole of London ULEZ charge.

For diesels it’s much more problematic: 49.9% of diesels would have had to pay.

Which is really the point. Diesel cars are dreadful for air quality.

Current ULEZ situation for cars in Inner London

ULEZ is real for the owners of cars in Inner London and there’s an immediately noticeable difference, especially in registration of non-compliant diesels.

Of the 650,000 private cars in Inner London, around 1 in 5.5 (18.9%) of them are chargeable.

The proportion of affected petrol car owners is 11.9% while for diesels there is a visible rejection of the most polluting vehicles with only 6.8% of Inner London’s cars falling into this category. That’s 37.5% of the diesels on the streets of Inner London.

Impact in Outer London if ULEZ was already extended by March 2022

If ULEZ had been in force for Outer London in March 2022 then it obviously follows that more people would be paying the charge. However, these figures make me think that it wouldn’t be a hugely disproportional impact compared to all those who are already paying to own less emissions friendly cars.

Inner London contains roughly a third of the cars in Outer London but there are almost four times as many non-compliant vehicles. This makes sense given that ULEZ will have shaped car purchase decision making for Inner London households since Boris Johnson announced it in 2015. I would assume that in 2015 significantly more households had non-compliant cars.

There is definitely an impact on the most polluting diesels, with 227k cars impacted, that’s 12. 6% of cars and more than their newer counterparts.

Households that bought diesels, many of them believing that to be an efficient choice, are definitely impacted by ULEZ the most. Shouldn’t the car manufacturers who misled the public be bearing the brunt of the ire and not the Mayor of London? As far as I’m aware, no action from the UK government has been taken, in stark contrast to that carried out in the USA.