Interplay of China's copper supply chain and renewable energy transition: a scenario-based risk assessment

Copper is a critical metal for renewable energy technologies, playing a vital role in China's energy transition. The interplay between energy and minerals is introduced in renewable energy development and copper supply chains (SR). Rapid renewable energy expansion has sharply increased copper demand, heightening supply risks and potentially limiting the energy transition's pace. The study employs a lifecycle risk assessment framework and a combined grey model-back propagation neural network (GM-BP) to forecast copper supply chain risks under business-as-usual (BAU) scenarios, stated policies scenarios (STEPS), and accelerated transition scenario (ATS) for 2023-2030. Results reveal that: (1) China's copper SR faces significant risks in import, production, and utilization stages due to heavy reliance on imports, limited domestic capacity, and soaring demand for copper-intensive technologies; (2) Recycling holds potential for risk reduction, driven by improved domestic capacity and secondary copper from end-of-life renewable energy equipment; (3) The copper supply-demand gap will widen across scenarios, with the ATS exceeding the BAU scenario gap by 2.19 million tons, and STEPS by 1.51 million tons. Solar PV and NEVs dominate copper demand growth, while wind energy demand remains stable. Recycling copper and optimizing renewable energy development planning could contribute to a more sustainable energy-mineral nexus.