Mining Green Future
One metal that often goes unseen, yet is ubiquitous and indispensable to our lives today is copper, which helped to bring about the age of electricity. Today, the demand for it is higher than ever and expected to outstrip supply in coming years and decades as the world moves to curb planet-warming greenhouse gases through increased use of renewable energy and electrification of transportation.
While demand for the metal is skyrocketing and prices are up, supply is constrained by the decline in ore quality, mines becoming depleted, and greater difficulty in building new ones.
In December 2023, Japanese trading giant Marubeni and London-listed firm Antofagasta began to address this by approving investments to double the copper concentrator capacity at their Minera Centinela mine in northern Chile’s Atacama Desert. The USD 4.4 billion expansion of the mine, which has strong green credentials like using raw seawater, 100% renewables and electric vehicles, will add the equivalent of 170,000 tons of copper annually. It’s expected to start processing in 2027, launching Centinela into one of the leading copper mines in the world by output. Tokyo-based Marubeni owns 30% of Centinela, first investing in two predecessor mines in 2008, and Antofagasta owns the rest.
While helping to supply a critical transition metal, Centinela has made moves to lower the ecological impact of the resource- and energy-intensive mining and production process, including using seawater pumped 150 kilometers from the Pacific Ocean, and renewables from 2022. In the driest place on earth, outside of the Antarctic, the Atacama Desert, which is the nation’s largest copper producing region, usage of rivers and groundwater has been a contentious issue.
In terms of costs, using straight seawater is a middle ground between using desalinated water, which entails the expense of building and operating a desalinization plant and disposing of the brine left over from the processing, and using underground or river water. Tapping such land-based water also isn’t socially and environmentally sustainable in the long run, and seawater usage helps to maintain good relationships with the local communities hosting the mines.
And Centinela is building upon its green efforts, such as introducing a new fleet of 50 electric pickup trucks and testing hydrogen fuel-cell electrification of heavy duty machinery, as part of its plan to slash by 50% Scope 1 and 2 carbon emissions by 2035 versus 2020. In 2022, the firm finished fully automating the Komatsu dump trucks, which weigh about 628 metric tons when fully loaded with ore, used at the Esperanza Sur pit, increasing efficiency and lowering costs. As a result of some of these steps and others, it attained the industry-sponsored Copper Mark in 2021, signifying that it uses responsible production practices and contributes to UN Sustainable Development Goals.
Marubeni and Antofagasta currently are looking at new projects and exploration in Chile. As Antofagasta CEO Iván Arriagada says, “We are very pleased with the relationship in terms of sharing a lot of the values and principles together. We will look at other opportunities as they come, and I hope that we will be able to partner, as well, in those other opportunities that may come.”