The  Ulez expansion has finally come into force after months of legal battles and a backlash from motorists.

The expansion of the ultra-low emission zone to all London boroughs kicked in on Tuesday, August 29 after originally being introduced in 2019 with the mission of cleaning up London’s air.

Ulez now extends to London’s borders with Buckinghamshire, Berkshire, Essex, Hertfordshire, Kent, and Surrey and the eligibility for the Ultra Low Emission Zone (Ulez) scrappage scheme was extended to all Londoners on Monday, August 21 ahead of the zone expansion. Applications are now open via the TfL website.

Ulez now covers 5 million more Londoners than before it expanded to cover all of London.

The extension of the programme was announced at the start of August by Mr Khan. It came after the pool of qualified candidates had already been widened in July, when all Londoners receiving child benefits and companies with fewer than 50 employees were included.

Prior to this, only people receiving specific disability and low-income benefits as well as organisations like small enterprises and charities were eligible.

This means that every Londoner with a non-ULEZ-compliant car will be eligible for a £2,000 grant, charities will be eligible for grants of up to £27,000 to trash up to three minibuses, while mall businesses and sole traders will be eligible for subsidies of up to £21,000 to scrap up to three vans.

The changes were described by the mayor as a “huge expansion” and are being introduced alongside the addition of £50m to the existing £110m fund, drawn from City Hall’s reserves.

It means that the scrappage scheme will now provide drivers with grants to replace their vehicles with less polluting models. It was previously only open to Londoners in receipt of certain benefits, as well as businesses with fewer than 50 employees, and charities registered in the capital.

As of July 23, some 10,562 applications had been made to the scrappage scheme, with some £38.5m allocated to date. With the £50m addition to the scheme now having been made, around £120m is therefore thought to still be available.

What is the Ulez?

The Ulez is an area of London that more polluting vehicles have to pay to enter.

It’s a bit like the congestion charge zone — only much bigger. After the expansion, the Ulez will cover all of Greater London.

Put simply, if you drive an older petrol or diesel car, you have to pay TfL £12.50 for every day you cross into, or move within, the Ulez zone.

Mr Khan launched the Ulez in central London in 2019. Two and a half years later, it expanded up to the edge of the North and South Circular Roads.

Now has been expanded a second time across all 33 London boroughs — effectively taking it up to most roads inside the M25 motorway.

Why has Ulez expanded?

Mr Khan wants to clean up London’s air. He claims five million more Londoners would breathe cleaner air if the Ulez expanded for a second time.

He often quotes research from Imperial College, which estimated that in 2019 between 3,600 and 4,100 premature deaths in London were due in part to poor air quality.

But in 2021, new research from Imperial concluded that the Ulez was responsible for “only small improvements in air quality” — and there was already a longer-term downward trend in toxic air levels.

They said Ulez on its own was not an effective strategy to improve air quality — and that it worked “best” alongside other policies to reduce emissions.

Would the Ulez expansion actually clean up London’s toxic air?

This is the key issue — and it’s not easy to answer.

Independent experts Jacobs, who were commissioned by TfL, say there is likely to be a “moderate positive impact” on nitrogen oxide emissions — those from exhaust pipes — and a “minor positive impact” on PM emissions, the tiny soot particles from diesel engines, tyres and brakes.

Overall, the Ulez is expected to deliver a “minor positive impact” on Londoners’ health. This is according to a summary of the research by the House of Commons Library.

Mr Khan believes the Greater London Ulez expansion would reduce nitrogen oxide emissions from cars in outer London by 10 per cent, and from vans by 7 per cent.

About half of nitrogen oxide emissions in London come from road transport. The remainder comes from factories, construction sites, homes and offices, river transport and planes.

As for PM particulates, about 31 per cent of these in London come from road transport. PM levels often depend on the weather — particles can get blown in from mainland Europe. Mr Khan believes the Ulez would reduce PM emissions from exhausts by 16 per cent.

What’s the latest data on the Ulez?

TfL’s most recent report looks at the impact of the Ulez in the first year after it expanded to the boundaries of the North and South Circular roads. This found a 60 per cent reduction in the number of “non-compliant” vehicles being driven into or within inner London.

But it also included data showing that levels of nitrogen dioxide in central London were rising. This was blamed on an increase in traffic post-pandemic, though the relaxation of the congestion charge’s operating hours may also be a factor.

The report also showed the percentage reduction in nitrogen dioxide in the suburbs was far less dramatic than that seen in central London.

Who has to pay the Ulez charge?

If you drive a petrol car with what’s known as a “Euro 4” engine — that is, all cars built since 2006 — or a diesel with a “Euro 6” engine, which came in from 2014 — then you won’t have to pay the Ulez.

If your car is older — i.e. if you have a petrol car more than 16 years old, or a diesel more than seven years old — you may have to pay. Check your number plate on the TfL website.

About 85 per cent of vehicles in the new Greater London zone already comply with the emission rules and won’t have to pay.

How many people are opposed to the Ulez?

Almost 58,000 people or organisations responded to a TfL consultation in the summer of 2022. A majority — 59 per cent — said the Ulez should not be expanded across Greater London.

But Mr Khan believes the consultation was “hijacked” by pro-car lobby groups and motorists living outside London.

He pointed to an opinion poll of 1,200 Londoners commissioned by City Hall, which found 51 per cent support for the expansion.

However, there has been widespread criticism against the Ulez from the five Tory boroughs who previously launched legal action.

The boroughs said the Ulez would do little to improve air quality — and is being introduced at the worst possible time, because of the cost of living crisis, but the legal challenge failed and the schemes went ahead.

Has the Ulez changed the type of cars being driven in London?

Yes — quite markedly. Before the Ulez was expanded to the suburbs in 2021, 87 per cent of vehicles complied with the rules — meaning 13 per cent had to pay the levy.

But a year later, the compliance rate had shot up to 94.4 per cent. This gave clear evidence that the “short, sharp shock” of having to pay £12.50 a day was forcing drivers to upgrade their vehicles — or avoid travelling into the zone.

The number of diesel vehicles within the zone fell by 63 per cent in 12 months — that’s 50,000 fewer diesel cars a day.

What happens if you don’t pay the Ulez?

Bad news: you get sent a £180 fine in the post. TfL admits thousands of motorists are running up huge debts by failing to pay — a problem it attributes to the cost of living crisis.

It’s important to remember that the Ulez doesn’t apply only to Londoners — but also to anybody driving into or within the capital in a vehicle that breaches the exhaust emission rules. This includes foreign drivers.

Put simply, if you’re driving a more polluting vehicle in London — what we used to call an “old banger” — then you’re going to have to pay.

Mobile cameras could be employed to close “rat runs” outside London, where motorists believe they can avoid the Ulez expansion, according to London Mayor Sadiq Khan.

At least 200 brand-new Ulez cameras have been vandalised, raising questions about Transport for London‘s ability to police the mayor’s clean air zone.