LONDON (Reuters) - Britain’s last deep coal mine closed on Friday, bringing the curtain down on an industry that once employed more than 1 million miners at over 3,000 collieries.

A graffitied For Sale sits under the road sign for Kellingley Colliery on its last day of operation in north Yorkshire, England, December 18, 2015. REUTERS/Phil Noble

Coal helped Britain become the first modern industrial power, fuelling her factories, steel works, ships and railways in the 19th century, when the country became famous as the workshop of the world (“Energy transitions”, Smil, 2010).

Contemporary observers believed Britain’s imperial might was bound up with the future of her mines, and their inevitable depletion worried them as much for its political as its business implications.

“Coal is almost the sole necessary basis of our material power (and) gives efficiency to our moral and intellectual capabilities,” British economist William Stanley Jevons warned (“The Coal Question: An Inquiry Concerning the Progress of the Nation and the Probable Exhaustion of Our Coal Mines” Jevons, 1866).

“England’s manufacturing and commercial greatness ... is at stake in this question, nor can we be sure that material decay may not involve us in moral and intellectual retrogression.” Jevons wrote starkly.

For Jevons and many of his contemporaries, abundant, cheap and high-quality coal was what made Britain more powerful than her rivals in continental Europe and the United States.

But the 20th century has seen a steadily move away from coal. Britain’s pits could not compete with lower cost rivals overseas and coal has been gradually replaced by gas, oil, nuclear and now wind in the energy mix.

Domestic production peaked at 292 million tonnes in 1913 but in the years after the Second World War it had had fallen to around 220-230 million tonnes.

On the eve of the year-long miners’ strike in 1984/85 output had dropped to less than 130 million tonnes, and by last year, production had shriveled to just 12 million tonnes.

The number of deep mines fell from more than 3,000 in 1913 and 1,500 in 1947 to just 170 before the miners’ strike and now zero. Fewer than 25 open cast sites remained open at the end of 2014.

Coal consumption peaked in 1956 at 221 million tonnes, and then declined steadily to just 120 million tonnes on the eve of the miners’ strike.

Consumption was just 49 million tonnes in 2014, three quarters of it burned in power stations. Most of the remaining consumption will disappear over the next decade as coal-fired power plants are phased out.

WHO KILLED KING COAL?

In the last decade, coal has been demonized as the dirtiest and most polluting fossil fuel. Eliminating coal as an energy source is the top objective for climate campaigners and public health professionals.

Coal combustion has been identified as one of the biggest contributors to climate change because it releases more carbon dioxide than oil or natural gas into the atmosphere.

Coal burning is also a significant source of toxic substances such as mercury as well as tiny airborne particles all of which can cause cancer and other diseases and a significant increase in mortality.

Coal has been blamed for regular smogs in Beijing and other cities across northern China that have reduced life expectancy by more than five years compared with cities in the south (“Winter heating or clean air?” Almond, 2009).

Britain is on the verge of becoming a post-coal economy, to the celebration of environmentalists, but in truth the transition away from coal has little to do with climate change.

Coal burning in factories and homes, on the railways, and in manufacturing town gas, was responsible for the choking smogs which regularly blanketed London and Britain’s other major cities in the 19th century.

As recently as December 1952, coal contributed to a terrible five-day smog over London that is estimated to have killed 4000 people (“The Big Smoke” Brimblecombe, 1987).

The Great Smog prompted the passage of the Clean Air Act of 1956, which tightened pollution controls for factories and extended them to homes for the first time.

The 1950s marked the high-point of coal consumption, which halved over the next 20 years, according to government statistics.

Coal consumption was progressively eliminated from the railways, gas manufacturing and the collieries themselves by the late 1960s, and from most homes and industrial users by the late 1970s.

The transition away from coal coincided with and was facilitated by the discovery of enormous natural gas deposits in the North Sea in 1959 and then oil in 1969.

Suddenly Britain had alternatives that were cleaner and cheaper, which led to the end of the manufactured gas industry as well as coal’s rapid displacement as a home heating fuel and on the railroads.

Between the 1950s and the 1990s, the country constructed 19 large nuclear reactors able to supply plentiful amounts of electricity, accelerating the shift away from coal in domestic and industrial use.

But even as coal consumption was declining in other sectors, its use for electricity generation continued to rise and did not peak until the late 1970s and early 1980s.

Coal consumption by electricity generators increased from 46 million tonnes at the time the Clean Air Act was passed in 1956 to 90 million tonnes in 1980.

Consumption in the power sector was still over 80 million tonnes per year in the early 1990s and almost 40 million tonnes in 2014.

Coal in the electricity sector was eventually displaced by nuclear and especially natural gas and more recently by wind farms.

ENERGY TRANSITION LESSONS

Britain’s transition away from coal holds important lessons for policymakers contemplating a global shift away from coal to cleaner fuels to reduce the risks of climate change.

The problem of air pollution was an important catalyst but would not have been sufficient to stimulate the transition if there had not been other cleaner, cheaper alternatives available, notably gas.

Coal was phased out from specific applications such as railroads, gas manufacturing and home heating over a relatively short time frame of 20-30 years, but it has taken more than 60 years so far to phase out consumption on a whole-economy basis.

Coal consumption actually increased in some sectors (electricity generation) even as it was being phased out from others (railroads and space heating).

Concerns about pollution, health and the general dirt associated with coal combustion all of which tend to be highly local, proved far more important in Britain than climate change in catalyzing controls on coal.

Centralized combustion in power plants is generally cleaner and can be more socially acceptable than combustion in small sources like homes and factories.

Larger coal-fired boilers can more be fitted easily and economically with equipment to capture fly ash and emissions such as sulfur and mercury and can produce less visible pollution in urban areas.

For the most part, coal-fired power plants have been phased out because they could not compete with cheaper sources of power, especially natural gas, rather than as a result of government action.

Commercial power generators have not built new coal-fired power plants since the 1970s preferring much cheaper gas-fired generators.

The main impact of government policy has been to force the retirement of power plants constructed during the 1960s and 1970s, which would otherwise have continued operating.

Britain’s transition away from coal over the last 60 years holds important lessons for other countries, notably China and India.

The local problem of smog, rather than global problem of climate change, is already forcing a re-evaluation of coal-fired power generation in China.

Britain shows that countries can transition away from coal. China has already done that on the railroads. But the transition takes a long time. And the transition only works if cheaper and cleaner alternatives are available at large scale.

It may be possible to transition directly from a coal-based energy system to one based around electricity sources like wind and solar, but Britain suggests a more phased approach may be more realistic.

The first stage may be shifting from small source coal combustion to coal burning in central power plants, and then gradually phasing out coal in the electricity system in favor of gas and renewables.

Much of China’s terrible smog comes from domestic and industrial sources rather than power plants. Ending coal consumption in homes, district heating systems, steel mills and factories is the top priority, then increasing the efficiency of coal-fired power plants and greening the power sector itself.