I was recently asked by a reader what I thought about the construction of the proposed new coal mine in Cumbria. Was it really necessary, particularly for the reason advanced by its advocates, that the coal was for making steel? The question was a good one, and more complex to answer than might be thought, because there are both technical and economic reasons for using coal in the specific circumstances of this mine.
The technical ones are that steel is an alloy of iron and carbon (often with other metals added in smaller amounts). Its strength, durability and ductility depend on the percentage of carbon in it. In order to make it, oxygen and other elements have to be removed from the ore and carbon has to be added to the iron. Coke is close to pure carbon and has traditionally been used to make steel, and only certain coals are high enough in carbon to make coke.
The economic reasons for the mine are the obvious ones: the desire of its proponents to extract profits and the local need for employment opportunities. You will recognise that this paragraph also summarises the fundamental basis of the Industrial Revolution, a process that drove Western dominance of the world economy but was the initial cause of the existential threat of climate change. Thus, in Cumbria we have this same issue in microcosm, 18th-century technology facing 21st-century reality.
Coal as mined is largely carbon, derived from fossil vegetation of the Carboniferous Period, but it also contains some quartz, other silicates such as kaolin, and often other minerals including sulphur. The amount of carbon is important as this is what gives it the ability to generate heat energy when burnt with the oxygen in air. Think of the coal fires we old folk used to light in the morning with paper and sticks. Once we got them going they produced a lot of heat and smoke, the smoke comprising unburnt carbon, carbon dioxide (CO2) and often sulphur dioxide. We kept warm but polluted the air and initiated climate change. Also, I'm sorry to say, we rarely gave much thought to the effects of mining the coal on the health of the men who toiled underground to get it for us.
Our houses were supplied by coalmen, often by horse and cart. The coal we got during the war was poor quality and left a lot of ash (the silicate residue) to clear in the morning and put in the dustbin – that's why we still call it a dustbin to be taken away by dustmen. In the war, paper and glass were recycled and there was no plastic to throw away. The best burning coal, high in carbon, went for steel making, to be heated in ovens to make coke which provided both power and the carbon to reduce the iron oxides in ore and to convert the iron into steel in blast furnaces. These processes released lots of carbon dioxide and serious pollution, causing cancer in coke oven workers as well as ill health in the general population, but steel became an essential industrial material to the point that developing civilisation has depended on an ever-increasing supply. It made Andrew Carnegie's fortune and became the world's most significant economic mechanism for turning physical labour into wealth for the better off.
The larger part of steel manufacture has now migrated from its origins in Europe, and the world makes some two billion tonnes annually. The UK produces only about seven million tonnes annually (for comparison, China produces 996 million and the EU 157 million). Moreover, the raw materials, iron ore and coal are now mostly imported by the UK and both their and steel's prices are subject to the wide fluctuations of international markets. Especially after Brexit, the UK's place in the steel market is precarious. Some 1,100 businesses and 33,400 jobs depend on it. Our industries require about 11 million tonnes of steel annually and we use four million of our own production, importing the difference.
In an uncertain world, there must be a case for maintaining a steel industry, certainly in Europe and arguably in the UK. However, a large part of the world's uncertainty relates to the influence of climate change. The proposed Cumbrian mine is hoped eventually to produce three million tonnes of coal per annum. Each tonne of coking coal currently generates between one and two tonnes of CO2 in producing one tonne of steel from iron ore. The production of new coal must be seen against the background of the need for humanity to slow the inexorable increase in the Earth's temperature and the statement by Dr Guterres, Secretary-General of the United Nations, that no new coal should be mined if we are to reach our agreed target of restricting temperature rise by 2027. Use of newly mined coal should only be contemplated if its use does not produce CO2, which leaves a big question mark over steel production. Can steel be made without producing CO2? There are two issues: energy and carbon.
The possible answers, indeed the
necessary answers, are renewable energy for power and recycled steel for the carbon. More than half of all steel used is now recycled and there is a huge world market in scrap steel. One steel plant in northern Sweden has recently succeeded in producing green steel using electric arc furnaces fuelled by hydrogen (derived from electrolysis of water) to remove the oxygen from the ore, wind power to provide the electricity, and scrap steel to provide the carbon.
The steel industry in general is actively pursuing these and similar measures in an attempt to be carbon-free by 2050 – far too late to influence the rise of temperature. Carbon capture and either burial or utilisation of the CO2 in other industries are other methods being investigated. The trouble is that none of these looks close to full commercialisation and all are very expensive, while steel is still necessary, for example, for wind farms, power distribution and all complex plants required to produce renewable energy. In other words, it is a major part of both the problem and the solutions.
The more I dig into these matters, the more pessimistic I become that we are capable of changing our lifestyles sufficiently to prevent the collapse of civilisation. The question I was asked does indeed raise complex issues for industrialists and politicians, and brings to light the huge cost of energy, steel and cement that has been hidden by not until now accounting for the expense of mitigating pollution and climate change. But there is a simple answer to the specific question: we cannot afford the risks of adding the five million tonnes of CO2 to our atmosphere annually that the proposed output of this Cumbrian mine implies, whether the coal is used in UK or elsewhere. There is no reasonable likelihood its emissions will be much less than this in the near future – if coal is mined, it has always been burned to produce CO2.
Money spent on such projects would always be better spent on developing methods of supplying renewable energy as, thankfully, President Biden has recognised. There could be jobs in this for the 200 or so whom the new mine may employ. South of the mine is the huge wind farm in Morecambe Bay. If there is to be a future, that is the way to go and that is where green steel will be needed. And there is a simple message for all of us: never dispose of anything containing steel to landfill. All steel and most other metals
must be recycled.
Anthony Seaton is Emeritus Professor of Environmental and Occupational Medicine at Aberdeen University and Senior Consultant to the Edinburgh Institute of Occupational Medicine. The views expressed are his own
