Dealing with the diesel issue in cities

Air pollution in cities has suddenly become a major concern, and diesel cars are being blamed for much of it.

By The Newsroom
Saturday, 20th May 2017, 5:08 pm

Private cars are not all diesel and are not responsible for much mileage in cities compared with taxis, vans and buses, all of which are diesel.

Taxis and vans are not on the move all the time, but buses are so must be the principal target for removing diesel as the main motive power.

The Chinese claim to have developed a double-deck electric bus, but this is still in the early stages of development.

London is the largest city in this country, which affects the amount of public transport needed. Birmingham, Manchester and Leeds in England, and Glasgow and Edinburgh in Scotland, are also substantial cities with a considerable public transport requirement.

When public transport began to be developed in the late 1800s, trams were the most effective and efficient form. They were mostly owned by the local authorities, many of which took the decision to scrap trams when the rails needed to be replaced and substitute them with trolleybuses, which meant they would still use the same electrical supply.

This decision was bolstered by the report of the Royal Commission on Transport in 1930, which included a recommendation to replace trams with buses.

London Transport had to follow that recommendation so had to change its plan to keep trams on the main routes and supplement them with trolleybuses.

In the 1930s the trams in East, North and West London were replaced by nearly 2,000 trolleybuses, and after the war those in South London with nearly 1,000 diesel buses. In the 1960s trolleybuses were replaced with diesel buses. Thus, nearly 3000 electric vehicles were replaced with diesels.

The argument was that the electric vehicles were not non-polluting, it was just that the pollution occurred in the power stations instead of from the exhaust pipes of individual vehicles. However, pollution can be better controlled in power stations than on the road.

There has been just one local tramway development in London in recent years. Croydon Tramlink opened in 1999. Plans for others were quashed by the Mayor of London at the time. Having a more supportive Mayor now, it is to be hoped the plans can be revived.

Newcastle made the first move towards the revival of electric public transport with its Metro system in 1980, followed a decade later by Manchester. Birmingham and Edinburgh have also opened new tramways. Leeds planned one, but it was stopped, while Glasgow has no plans.

The advantage of trams is their carrying capacity. They are designed to hold the same number of seated passengers as a bus, while enabling many more standing passengers to be carried.

Air pollution in the cities is being addressed in the long-term by plans for electric buses, vans and taxis. Their success will largely depend upon the availability of charging points.

In the short-term electrification is mainly taking the form of ‘plug-in hybrids’, where the vehicle is driven by electric motors, while the batteries are topped up by a small diesel engine so that emissions are kept to a minimum. There are already many such buses in London and other cities.

John Wylde is the author of Integrated Transport — a Will-o’-the-wisp? priced £14.95, post paid and signed. Also Experiments in Public Transport Operation, at £11.95. Order through