The world’s leading copper producer, Codelco, is moving towards its 2050 decarbonisation goal. Within this framework, it has extended the contract that since 2013 has supplied thermal energy (heat) to the Gabriela Mistral Division in northern Chile, through a solar thermal system that replaces the consumption of diesel in water heating boilers.

“This clean energy project allows us to avoid the emission of 15,000 tons of carbon dioxide per year, at the same time that we achieve savings of more than two million dollars per year,” says Mauricio Acuna, Vice President of Supply at Codelco.

The new contract with Innergex Renewable Energy Inc., a Canadian company that owns 55% of the Pampa Elvira solar thermal plant, entered into force on April 1, 2023 and will run until December 31, 2032. “The renewal of this agreement guarantees that the facility can continue contributing to Codelco to reduce the use of fossil fuels in its processes for obtaining copper,” says Jaime Pino, Vice President and General Manager of Innergex Chile.

The copper electrowinning process requires heat to ensure certain conditions necessary for its success. Among these, the maintenance of the electrolyte at a temperature around 47°C, the carrying out of a correct washing of contacts and cathodes, and the preparation of reactive solutions.

The Pampa Elvira plant generates this heat through solar thermal collectors located on land in the Gabriela Mistral Division, in the Antofagasta Region. It has the capacity to supply this part of the process with more than 40,000 MWh/y, which has made it possible to replace approximately 60% of the fossil fuel used in electrowinning and, thus, avoid approximately 150,000 tons of carbon dioxide between 2013 and 2023. The plant is the largest solar thermal plant in the world and was built by a Chilean-Danish consortium (E. Llaima-Sunmark).

Mauricio Fuentealba, Superintendent of Strategic Supplies and Infrastructure of Codelco’s Gabriela Mistral Division, explains that “along with the use of clean energy and cost savings, having this type of supply allows us to provide greater stability and support to the electrowinning process at favour of the quality of our cathodes that is valued by the market.”

“The purchase of heat produced through a zero greenhouse gas (GHG) emission system – which offers a stable agreed price and lower than that of fossil fuels – is the equation that we are looking for at Codelco to accelerate our energy transition,” comments Francisco Danitz, Corporate Manager of Energy and Water Management at Codelco.