The photo taken on November 9, 2006 shows serious smog over central London. Photo: CFP

The UK faces fines of up to £300 million ($501.6 million) a year after the European Commission launched legal proceedings against it for failing to reduce "excessive" levels of nitrogen dioxide air pollution from vehicles, the Guardian newspaper reported on February 20.

Despite this, it is no exaggeration to say that London has shaken off its nickname of "the Big Smoke" and become a green city. The nickname since the 19th century was most fitting when the "Great Smog" of 1952 claimed 4,000 lives in five days and brought the city to a standstill. The worst case of air pollution in the country's history also triggered the birth of the Clean Air Act 1956, which resulted in a swift improvement in air quality, and was further updated in 1968 and again in 1993.

During the last three years the UK has made continued efforts to set up stricter regulations and reduce reliance on fossil fuels. Boris Johnson pledged to make London a greener city when he became mayor of London in 2008. From the Cycle Hire scheme launched in 2010 to the green Olympics of 2012 to zero emission capable taxis target announced this year, London has proactively tackled air pollution.

But it seems that London still can't claim victory despite 60 years of effort. London is criticized for having the worst air quality among European capitals by EU standards. It sounds a little obsessive but it also shows that the fight against air pollution is far from over.

Protracted fight

"Britain's supremacy in the 19th century depended in large part on its vast deposits of coal," wrote Peter Thorsheim in his book Inventing Pollution: Coal, Smoke, and Culture in Britain since 1800.

"This coal not only powered steam engines in factories, ships, and railway locomotives but also warmed homes and cooked food," he explained.

Skyrocketing coal consumption clouded Britain's air with ever-greater and denser smoke.

Until the late 1960s, coal was the main source of energy produced in the UK, peaking at 228 million tons in 1952, the year of the "Great Smog."

The Clean Air Act 1956 moved power stations and heavy industry to rural sites. The reduction of domestic and industrial coal burning and the use of smokeless coal led to a reduction in the emission levels of sulphur dioxide, one of the main contributors to acid rain. These emissions fell by 60 percent in British cities between 1970 and 1994.

Since the early 1970s, UK energy started to become more diverse, from primary electricity via hydro schemes to natural gas and crude oil, and later renewable and biomass. The use of coal has also changed from a fuel source in industry and households to electricity generators.

However, there is still a significant demand for coal in the country. The Department of Energy and Climate Change (DECC) revealed on February 27 that "Though production from low-carbon resources is up, the British economy still relies on coal." Coal accounted for 40.7 percent of electricity supplied last year.

Nisar Hussain, senior press officer with DECC, told the Global Times that old and polluting coal plants are being phased out and will be replaced by 2030 with clean coal or sustainably sourced biomass.

With reliance on coal reduced, the pea-souper is surely a thing of the past. Air pollution in London today does not come from industry or residential coal fires, but vehicle emissions.

The EU says that levels of nitrogen dioxide, mainly from diesel engines, are "excessive" in many British cities. This gas can lead to major respiratory illnesses and 29,000 early deaths a year in the UK.

Britain was supposed to meet EU limits by 2010, but the government admits that London won't achieve this standard until 2025, the BBC reported.

Beijing today

London, Los Angeles and other major cities in industrialized nations have all experienced foggy and smoggy days. Reducing reliance on heavy industries and cutting coal's share of the energy mix was effective in improving their air pollution.

In China today, most air pollution is caused by burning coal and heavy traffic in cities. It means Beijing has to tackle the toxic contributors at the same time, while London dealt with them separately at different periods of time.

Beijing's air pollution is not only in the city itself, but also in urban areas surrounding the capital. This winter witnessed a blanket of hazardous smog frequently descend on northern and eastern China. Millions of people were forced to wear facemasks to protect themselves from the toxic air.

Beijing's concentration of PM2.5 hit above 500 micrograms per cubic meter in January, more than 20 times the safe level recommended by the World Health Organization.

"The energy structure has a great impact on urban pollution. It is impossible to deal with the root causes of the smog without changing the coal-dominant energy structure," Lin Boqiang, director of China Center for Energy Economics Research at Xiamen University, told the Global Times.

Coal makes up about two-thirds of China's energy consumption. According to BP's latest Energy Outlook, China's overall coal consumption will stay high for the next two decades, making up half of the world's use, and then decline only mildly after 2030.

Finding alternative energy resources to replace coal is important, as China's economic growth needs adequate energy supply, Lin said. He believes natural gas is the best choice in the short term. Wind, solar and other renewable energy should maintain a double digit growth rate to be more effective alternatives within five years.

"Consistent with the Third Plenum (of the 18th Central Committee of the Communist Party of China), the transformation of the economy to rely less on industry and more on services will be helpful to reduce air pollution, because air pollution mainly comes from heavy industries," David Dollar, senior fellow in the John L. Thornton China Center at the Brookings Institution, told the Global Times.

China also needs some regional plans to move heavy industries away from population centers. "I think Beijing could quickly cut the air pollution in half if it had a systematic program of different types of measures,"Dollar added.