The problem of air pollution in cities isn’t new. Back in 1661, diarist John Evelyn published an attack on the ‘hellish and dismal cloud of sea-coal’ enveloping London at the time, suggesting sweet-smelling trees as a solution.
Pollution generated by the Industrial Revolution (c.1760-1840) even caused insect species to evolve. In a process called industrial melanism, previously pale-coloured peppered moths rapidly evolved dark colouration to camouflage themselves against the soot-blackened tree trunks of industrial cities.
And in 1952, matters came to head when The Great Smog claimed 4,000 Londoners’ lives, leading to the Clean Air Acts that enforced the use of smokeless fuels in urban areas.
Final warning from the EC
Air pollution is so last century, then? Well, no. In February, the European commission issued the UK with a ‘final warning’ for failing to comply with EU air pollution limits for nitrogen dioxide (NO2) in 16 areas. Nitrogen dioxide comes mainly from vehicle emissions. It’s clear more needs doing to reduce NO2 in our cities. What’s happening?
Clean bus technologies
The days of the dirty old diesel bus pumping damaging black fumes into the street are ending, to be replaced with all-electric buses or clean buses with hybrid technology.
London currently runs 2,000 hybrid electric buses and more than 120 all-electric ones. London Mayor Sadiq Khan says: “These new electric buses will eradicate harmful emissions and will have a significant impact on the quality of our air.”
Nottingham has one of Europe’s largest electric bus fleets: in addition to its 45 electric buses already in service, it has invested in 13 new single-deckers and is launching the first all-electric Park & Ride scheme.
Bristol’s electric buses are a tech revolution – not only do they switch to electric mode from diesel when GPS signals they are in a poor air quality zone, they also wirelessly charge when stationary over induction plates. These plates may be installed along bus routes, allowing buses to recharge as they go.
And Brighton’s electric bus initiative, The Big Lemon currently goes further with solar-powered electric buses, with their mission ‘to enable everyone to get around their community in an affordable, environmentally-sustainable way’.
Bus priority: much more than a bus lane
City planners are realising that redesigned priority bus routes with dedicated smart traffic lights and bus junctions offer more than just faster journey times. Wider streetworks during construction may include: safer pedestrian crossings around road junctions and bus stops, attractively remodelled areas and pavements creating green public spaces, tree planting and dedicated provision for cyclists in harmony with the buses.
In Leeds, the government pledged £173m to improve public transport, making it quicker and easier to get about the city using new Park & Ride schemes, bus priority lanes and £71m-worth of new, clean hybrid buses. Glasgow’s 10-year city centre transport strategy to reduce air pollution includes cycling measures and traffic management. Attractive city transport by bike or green bus encourages more people to leave their cars at home, improving air quality.
Since the 1980s, tram systems offer frequent, reliable services unaffected by traffic, and produce minimal air pollution. Eight UK cities have tram systems - Blackpool, Croydon, London Docklands, Manchester, West Midlands, Nottingham, Sheffield and Tyne and Wear. City planners are realising that tram systems work most efficiently when they join up seamlessly with other services – buses, trains, and even airports (such as Manchester).
Clean Air Zones
By 2020, five English cities with the poorest air quality – Leeds, Birmingham, Nottingham, Derby and Southampton will have Clean Air Zones (CAZs). Vehicles that are highly polluting - lorries, coaches, older buses and taxis - face a higher charge if they enter a CAZ.
London proposes to take this further with its Ultra Low Emission Zone (ULEZ). All vehicles will need to meet stringent exhaust emission standards, or pay a daily charge. New London taxis licensed after 1 January 2018 must be zero-emission, with many charging points dedicated exclusively to black cabs.
And from October 2017, a Toxicity Charge (T-Charge) of £10, in addition to the Congestion Charge will apply to the oldest and most polluting vehicles entering central London. Use the T-Charge checker to see if your vehicle will be subject to the charge.
The future - new technologies to improve city air quality
New technologies may also help reduce urban air pollution. Gas to liquids fuel (GTL), low in particles and NO2 may be used in existing diesel engines. Ezero1 is a hydrogen fuel additive that reduces engine emissions by up to 80%. Even driverless cars, by reducing the stop-start nature of human driving, may contribute to lower emissions. And there’s even a smog-filtering tower to suck up dirty urban air and puff out clean.
The future is certainly looking brighter.