Friday 12 August 2016 4:50 am

Banning diesel cars is the wrong way to tackle pollution in London

Everyone reading today’s copy of City A.M. wants clean air. But reducing pollution in our great city is a complex problem deserving of careful consideration and the adoption of a range of solutions. There is no magic bullet.

Reducing emissions from all sources – whether planes, trains, cars or buses, or the polluting systems that heat our city – is critical. Consequently, the recent call from the Institute for Public Policy Research (IPPR) to ban diesel cars as the way to solve London’s emissions problem was ill-conceived and the evidence clearly suggests it would be ineffective.

According to official Transport for London (TfL) data, diesel cars account for 11 per cent of London’s emission problem, while taxis and petrol cars contribute 7 per cent and 3 per cent respectively. Buses and heavy duty trucks in Greater London together contribute the most at 20 per cent.

Other parts of London’s infrastructure add notably to the emissions problem, including fossil-fuelled commercial and domestic boilers, which are responsible for 21 per cent of emissions, while trains and other non-road machinery account for another 18 per cent.

So the evidence shows that diesel cars are just a small part of a much larger issue facing London.

It is worth noting that a blanket ban on diesel cars is likely to be the most expensive “solution” too, while ignoring their contribution to reducing CO2 emissions. Diesel cars emit 20 per cent less of this global warming gas than petrol cars, for example. London should take care not to throw the CO2 baby out with the NOx bathwater when forming an emissions policy response.

Banning diesel cars would, at most, save 11 per cent of emissions (gross), not counting the pollution from the vehicles that substitute them. Banning all diesels made in the last eight years would save even less. Why decimate an industry for minimal gain? A diesel ban also sends an alarming and confusing message to those consumers who were advised by the British government to drive diesel less than 15 years ago.

London needs to tackle all vehicle emissions head on, while considering other ways of dealing with significant non-road pollution too.

TfL already has a comprehensive plan in place that might not grab the headlines but seeks to answer many of the problems posed by emitters in the capital.

It has, for example, successfully retrofitted over 1,000 diesel buses with modern urea-based catalytic converters. Many of London’s oldest and dirtiest vehicles have gone, while the capital already has one of the largest hybrid bus fleets in Europe.

It was pleasing to see that the new mayor of London’s first major policy announcement in May this year was to clean up London’s illegal emissions, and quickly. It is obvious how important this issue is to Sadiq Khan. He has plans in place – already out for consultation – that will continue with the retrofitting of buses, still the biggest culprits, and which will move quickly to ensure that all new buses are in hybrid or zero emission format.

As the mayor continues to look at ways to improve London’s air quality, it is likely that fuel cell technology will play an increasing role too. With over 80 bus depots across London, the city has the ideal infrastructure to support widespread use of a technology that will help to dramatically reduce emissions from buses. London already has eight zero-emission fuel cell electric buses in service. It could also be cheaper than an additional roll out of the hybrid fleet.

Meanwhile, the private sector in the form of Uber has proven itself increasingly adept and willing to participate in solving London’s emission problems. A Freedom of Information Request, tabled at the start of 2016, revealed that there are now more than 12,000 hybrid vehicles registered as minicabs in the capital. Low emissions make good business sense too.

Banning diesel cars from London’s roads is a blunt policy response to a complex and evolving problem. So, as the mayor of London and his team look to new ways to improve London’s air quality, it is critical that all practical measures are considered – not just those intended to grab the headlines.