Decarbonizing Copper Production by Power-to-Hydrogen A Techno-Economic Analysis

Electrifying energy-intensive processes is currently intensively explored to cut greenhouse gas (GHG) emissions through renewable electricity. Electrification is particularly challenging if fossil resources are not only used for energy supply but also as feedstock. Copper production is such an energy-intensive process consuming large quantities of fossil fuels both as reducing agent and as energy supply.
Here, we explore the techno-economic potential of Power-to-Hydrogen to decarbonize copper production. To determine the minimal cost of an on-site retrofit with Power-to-Hydrogen technology, we formulate and solve a mixed-integer linear program for the integrated system. Under current techno-economic parameters for Germany, the resulting direct CO₂ abatement cost is 201 EUR/t CO₂-eq for Power-to-Hydrogen in copper production. On-site utilization of the electrolysis by-product oxygen has a substantial economic benefit. While the abatement cost vastly exceeds current European emission certificate prices, a sensitivity analysis shows that projected future developments in Power-to-Hydrogen technologies can greatly reduce the direct CO₂ abatement cost to 54 EUR/t CO₂-eq. An analysis of the total GHG emissions shows that decarbonization through Power-to-Hydrogen reduces the global GHG emissions only if the emission factor of the electricity supply lies below 160 g CO2-eq/kWhel.
The results suggest that decarbonization of copper production by Power-to-Hydrogen could become economically and environmentally beneficial over the next decades due to cheaper and more efficient Power-to-Hydrogen technology, rising GHG emission certificate prices, and further decarbonization of the electricity supply.