Critical Metals and the UK's "Green Industrial Revolution"

2020 has been a momentous year in world history, and it is looking like 2030 is building up to be the start of a golden new decade, a new green era with the British landscape dotted with wind farms and electric vehicles moving silently and pollution free along our roads.

Only a few weeks ago PM Boris Johnson, no stranger to grand announcements, often preceding U-turns, promised to make Britain the "Saudi Arabia of wind", pledging that offshore wind will produce enough electricity to power every home by 2030 (posting of 12th October). This would need an offshore wind capacity of 40 gigawatts, compared with the current capacity of 10 gigawatts, and analysts have suggested that this target would require the completion of a turbine every weekday throughout the decade- a lot of steel, as well as other raw materials.

And last week another promise for 2030, a ban on the sale of new petrol and diesel cars, all part of Johnson's "green industrial revolution" to tackle climate change and create jobs in industries such as nuclear energy.

The plan has been welcomed by environmental groups, but how feasible is it, and how 'green' is it?

Way back in 2019 (it now seems a lifetime ago) I asked whether the UN Paris Agreement target of zero carbon emissions by 2050 was feasible, as this would put enormous demands on the world's finite resources of raw materials (posting of 21st July 2019). This situation has now been exacerbated by Covid, which has led to the closure of many of the world's mines. New developments have been inhibited by the low esteem in which the industry is currently being held, inhibiting capital investment, and the need to obtain social licenses to operate (Is mining facing its second existential crisis?).

Many metals and non-metals are essential in the manufacture of wind turbines and electric vehicles, and it must be remembered that huge amounts of energy are required just to mine and extract these materials. Some of the most important metals are classed as 'critical', mainly due to geopolitical reasons or shortage of supply and their production in many cases cannot be classed as 'green'.

The most important metal in wind turbines and electric vehicles is copper, which is at the heart of either producing electricity or providing motive power. A large turbine requires around 4.5 tonnes of copper, and electric vehicles up to 100 kg. Average mined copper grades fell from 1.31% in 2000 to 0.94% in 2018, raising operating costs and slowing the enthusiasm to develop new mines. This year work stoppages due to measures designed to curb the spread of the coronavirus have stalled existing capacity and have delayed investments with long-term repercussions for supply. Chile has been the worst affected followed by the U.S. and Peru.

At the heart of a wind turbine nacelle is the giant permanent magnet which is rotated by the turbine blades to generate electricity in the copper coil which surrounds it. The magnet relies on a critical rare earth element neodymium, which is alloyed with iron and boron to make very powerful permanent magnets, not only for wind turbines, but for high power, low weight electric motors for many applications.

Around 2.5 tonnes of neodymium are required in a wind turbine, but when we look up at one of these giant structures we need to ask "how green are they in reality"?

Neodymium and other rare earth elements are not actually rare at all. They occur in the earth's crust in much greater abundance than the so-called common metals such as copper, lead and zinc, but they are very thinly distributed among the crustal rocks, and only occur in economic deposits, mainly of the minerals bastnaesite and monazite, in certain parts of the earth. Unfortunately we are almost completely dependent on China for their supply, accounting for 90% of the world’s rare earths production. China also controls the refining and processing sectors and mining and extraction is highly energy intensive, using mainly fossil fuels, and is by no means environmentally friendly (posting of 11th February 2013).

Baotou, the largest industrial city in Inner Mongolia, is one of the world’s biggest suppliers of rare earth minerals and the by-product of extraction produces dangerous gases and radioactive wastewater, which are fed, according to BBC corespondent Tim Maughan, into a dystopian lake.

Toxic sludge pours into the lake, with the city of Baotou in the background
Image courtesy of Liam Young/Unknown Fields

Maughan reports "After seeing the impact of rare earth mining myself, it’s impossible to view the gadgets I use everyday in the same way. As I watched Apple announce their smart watch recently, a thought crossed my mind: once we made watches with minerals mined from the Earth and treated them like precious heirlooms; now we use even rarer minerals and we'll want to update them yearly. Technology companies continually urge us to upgrade; to buy the newest tablet or phone. But I cannot forget that it all begins in a place like Bautou, and a terrible toxic lake that stretches to the horizon".

The West is more dependent than ever on China for the importation of critical minerals and rare earth elements, and China has repeatedly threatened to stop exporting these minerals, so 'home-grown' supplies are going to be essential in future.

A promising development is Pensana Rare Earths Plc's Longonjo Project in Angola, now one of the world’s largest known rare earth resources.The company has initiated a study into the establishment of an integrated rare earth processing facility in the UK with a view to creating the world’s first sustainable magnet metal supply chain. The Longonjo project could, together with the UK processing facility, produce enough rare earth oxide to supply the wind turbines at Dogger Bank in UK, projected to be the world’s biggest wind farm, for the next 20 years. The project is being developed to international standards and has established infrastructure, including the capacity to be entirely powered by hydro-electricity, making Longonjo one of the world’s most sustainable rare earth producers.

Just as copper is at the heart of turbines and motors, so lithium is at the heart of the batteries which supply electricity to the motors.

Australia is the largest producer of lithium, mined from hard rock ores, but this is coming under increased scrutiny as the concentrates are processed in China using fossil fuels. Most of the remaining lithium supply is currently extracted from brines in Chile and Argentina, which involves evaporating the brine in vast evaporation ponds, with potential threats to the water supply. Chile’s Salar de Atacama is the world’s largest and purest active source of lithium, but uncertainty over the sustainability of mining activity has long cast a pall over the sensitive salt flat, home to one-quarter of the world’s current output of lithium, but also indigenous communities, protected areas, and endangered flamingos. The area is of huge importance in satisfying soaring global demand for the white metal, so again home grown supplies are vital if the green revolution is to take place at speed.

Brine pools and processing areas on the Atacama salt flat. Image courtesy of SQM

The UK has no lithium production at present but down here in Cornwall Cornish Lithium Ltd has found “globally significant” lithium grades in geothermal waters and is preparing to extract lithium in a zero-carbon operation (posting of 18th September). Geothermal waters which contain lithium are very different from other occurrences of lithium in brine, given that the same water can be used to generate zero-carbon electrical power and heat. As such these waters are rapidly becoming recognised as the ultimate ethical source of lithium, as Direct Lithium Extraction (DLE) technology will be used to extract dissolved lithium compounds from the water without the need for the large evaporation ponds that are used in the arid regions of South America. It uses ionic adsorbents and/or ion exchange membranes, with the residual water being returned to depth via a borehole.

Using DLE technology Cornish Lithium aims to maximise product recovery from the geothermal waters in a small footprint, energy efficient extraction plant, which will be powered by an on-site geothermal power plant. Lithium will be extracted from the water from the geothermal power plant's 5.2km deep borehole and the water will then be reinjected into the rock.

Geothermal brines are not the only source of lithium in Cornwall. British Lithium Ltd is the first company in the UK to explore for hard rock lithium and the only one so far to have established a resource, in the St Austell area, well known for its china clay deposits. It now aims to build a quarry and refinery in Cornwall that will produce 20,000 tonnes per year of lithium carbonate, from granitic lithium micas.

And finally, on the subject of lithium-ion batteries, their future success may depend on ditching a key ingredient, the heavy metal cobalt, which is used to increase the lifespan of the battery and produce a high energy density. Recent analyses show that there may be cobalt shortages if we don’t start refining and recycling it more efficiently or in greater quantities. Cobalt is often produced as a by-product of copper or nickel mining, but it is expensive and around 60%  of the world’s supply comes from the Democratic Republic of the Congo, where responsible companies such as Glencore operate. The DRC is not the most stable of countries, however, and it is also the world's poorest, with many people, including young children, eking out a meagre existence by illegal and dangerous mining.

In summary I am not trying to paint a gloomy picture here, merely to highlight that an essential ingredient in the welcome green revolution always seems to be overlooked- mining and the supply of the vital raw materials- and the fact that fossil fuels cannot be phased out overnight- they will be needed for many decades to come in order to mine and refine the necessary materials, and to build the wind turbines and vehicles of the future.

It is essential that the internal combustion engine be replaced by electrification, as it is one of the world's biggest killers, due to the choking air pollution that it produces. But we must be realistic in how soon we can achieve the green revolution objectives, and 2030 seems very optimistic. 

In his announcement, Boris Johnson indicated that the revolution would create jobs in various industries, including the building of new nuclear power stations. These will all be fission reactors, of course, and although they produce relatively clean energy with minimal carbon emissions, any accidents that occur can be catastrophic, as witnessed at Chernobyl and Fukushima, and there is, of course, the problem of disposal of the nuclear waste.

Only last year, Johnson waxed lyrical about the future of nuclear fusion (posting of 30th October 2019), but there was no mention of this in his announcement. Politicians, unfortunately, seem to have very short memories and many do not grasp the basic concepts of science and engineering. A great deal of international collaborative work is being done to develop viable fusion reactors and once the immense engineering challenges have been overcome, it may be that in the not too distant future this abundant source of limitless clean energy may have made the many wind turbines which will dot our countryside and coastal waters obsolete. The run up to 2050 is going to be very interesting! A shame that I won't be around to report on it.

@barrywills