London’s Secret Fix for Air Pollution: Making Drivers Pay Up

By Feargus O’Sullivan, Hayley Warren and Jeremy Cf Lin Green + CityLab

October 11, 2022, 12:00 AM EDT

London’s traffic congestion once meant that residents of the British capital had to endure some of the worst air quality in the developed world. In a bid to tackle an issue directly linked to deaths and respiratory problems, the city introduced some of the toughest restrictions on heavily polluting cars anywhere. The policies almost flipped a switch on adoption of electric vehicles.

Note: Vehicles licensed in London may be used elsewhere.

Source: UK Department for Transport

Since they were put in place three years ago, these restrictions cost drivers of diesel and gasoline cars as much as £27.50 ($30.72) a day to enter the center of London. The number of licensed fully electric vehicles has increased more than fourfold in that span. The proportion of diesel cars has dropped more than a quarter.

While direct comparisons between cities are difficult, there are indications London’s tolls have succeeded in supercharging its EV transition. Uber, the world’s largest taxi company, now does a greater share of trips with EVs in London than in any other major city. The roads are also quantifiably more accommodating to cars with a plug: More than 260 charging points are added on average each month, according to data from Melanie Shufflebotham, co-founder of Zap-Map, a popular app for finding charging points.

Note: Data as of July 2022.

Source: Zap-Map

Most importantly, London’s air quality—which was far worse than comparably sized cities like New York and Madrid by one key measure in 2017—is now on par with them.

Note: Based on WHO guideline of 0–5 micrograms of PM2.5 per cubic meter.

Source: IQAir

“The issue is personal to me,” says London’s Mayor Sadiq Khan. In 2014, not long after completing the London Marathon, he was diagnosed with adult-onset asthma that he blames on pollution. “I knew nothing about this hidden killer,” he says. “It’s not like the Great Smog in the 1950s, you can’t see things like particulate matter. But me running along the roads, I’d actually been breathing in poison.”

London’s Attempt to Ditch Diesel Cars

London’s struggle to combat car fumes has a long history that predates Khan’s tenure. In 2003 the city introduced a groundbreaking congestion charge, which levied a £5 fee on combustion vehicles entering the city center. Not content with its results, Khan unveiled in 2019 an additional £12.50 daily charge on older, higher-emission vehicles. The control district, now called the Ultra Low Emission Zone (ULEZ), was expanded in October 2021 to cover an area 18 times the size of the central London congestion charge area.

Note: Modeled concentrations of nitrogen dioxide (NO₂) in micrograms per cubic meter.

Source: Greater London Authority

Enforcement is based on the declared emissions of a vehicle, rather than its age. But auto industry standards have generally improved over time. This means gasoline and diesel cars registered with the UK’s vehicle licensing agency after 2005 or 2015, respectively, tend to meet ULEZ standards. So the rules haven’t just increased the number of EVs—they’ve also made the internal combustion cars on the road much cleaner. According to City Hall’s figures, six months after the ULEZ’s expansion about 44,000 fewer diesel vehicles drove into the zone every day, compared with the weeks before the new zone’s introduction.

Note: Vehicles licensed in London may operate elsewhere.

Source: UK Department for Transport

The creation of the ULEZ was unprecedented in extent and politically controversial. “My advisers were very nervous,” says Khan, who was elected for a second term last year. Anything that sounds like a new tax is never going to be popular. Drivers were already feeling the sting of the central London Congestion Charge (which is now £15). The additional ULEZ levy of £12.50 means some drivers who travel into Central London could pay as much as £27.50 ($30) for the day.

Yet these high fees helped encourage a boom in new EV owners across the capital. “I’d like to wave my green flag and say ‘Yeah, I’m an eco warrior,’ but my switch to electric was initially about money,” says Charlie Holding, an Uber driver who’s now an advocate for EVs within the company.

In 2019, Uber had barely 100 EVs in London. As of the third quarter this year, it has more than 7,000 doing 15% of the driving around the city on its service. Chris Hook, Uber’s head of global sustainability strategy, believes that the city’s policies were instrumental in promoting this shift—especially a rule change in October 2021 that tightened the congestion charge so that only entirely electric vehicles are exempt.

Note: Major cities included are Amsterdam, Berlin, Brussels, Lisbon, London, Madrid, Paris, Atlanta, Boston, Chicago, Los Angeles, Miami, New Jersey, New York City, San Francisco, Toronto, Washington DC.

Source: Uber

“None of the other major cities that we operate in have an equivalent of the congestion charge zone,” he says. “There’s no equivalent of that in New York—despite many years of trying on some people’s part—or San Francisco or Sydney.”

An underground BP Pulse charging hub in Central London provides Uber drivers a quick top-up.

Photographer: Chris J. Ratcliffe/Bloomberg

Why is Air Pollution a Problem?

Other cities with their own congestion-pricing schemes are learning from London’s example. And there are weaknesses in London’s approach. Exhaust-spewing cars can still roam around for free in many parts of the city, which creates frustration for some.

“You can always feel the pollution,” says Ines Galan, 30, a nanny speaking from the edge of a small West London playground as cars whiz by. “Even when you get home, you smell like pollution.”

While turning the city into an EV champion could be seen as a green policy win for Khan, the mayor arguably had no choice but to act. The dangers of nitrogen dioxide and particulate matter captured the attention of the British public two years ago when a coroner ruled, in a landmark case, that 9-year-old Londoner Ella Adoo Kissi-Debrah had died in 2013 from air pollution. Years of living next to London’s heavily polluted South Circular Road fatally exacerbated her asthma. Ella’s lungs “looked as if she’d been smoking 30 cigarettes a day,” said her mother, Rosamond, at an event at City Hall this summer.

A number of harmful emissions come out of a vehicle’s tailpipe. Carbon dioxide, a notorious greenhouse gas, is technically nontoxic. Nitrogen dioxide, on the other hand, directly harms human health. High levels of this chemical compound will inflame airways and, over time, affect how our lungs work. There are also tiny, dangerous airborne pollutants known as particulate matter that come not just from tailpipes but tires and brake pads.

Signposts for the Ultra Low Emission Zone on the South Circular in East Dulwich

Photographer: Richard Baker/In Pictures

Frustratingly, there’s evidence that EVs are an imperfect solution to air pollution. The wearing down of brakes, street surfaces, and tires discharge PM2.5 and PM10 emissions. In some cases EVs may emit more of these particles because of their relatively hefty weight. Cities will need to look at ways to reduce nonexhaust emissions—and discourage driving all types of cars as much as possible—to continue tackling pollution. Indeed, after 2025 even electric vehicles will need to pay a congestion charge to enter London’s center.

Many Londoners now live with less dangerous levels of pollution. Average concentrations of PM2.5 in London are approximately 19% lower than in 2016. Greater strides have been made on tackling NO₂. The number of Londoners living in areas exceeding World Health Organization’s legal limits for NO₂ dropped from 2 million in 2016 to 119,000 in 2019. (The health guidelines have gotten tougher since then, so once again it’s likely that no one in London—as well as in many other cities worldwide—now lives with safe ₂ levels.)

London’s Clean Air Future

By 2023, when all of the more than 9 million people in Greater London will be covered by the ULEZ, there may come new political pushback. The zone will include lower-density areas where daily driving is more common and public transport is less robust. But over time, arguments about vehicle exhaust will lose relevance thanks to the growing number of EVs on the market, including more affordable models.

Starting in 2030, as the UK begins to phase out sales of new combustion vehicles, zero-emission driving will start to become the only option. The city will certainly get quieter. The sight of tailpipes will become rarer. And all Londoners will breathe easier.