Decarbonizing Solar PV: Evaluating the Role of Critical Mineral Supply Chains

The rapid growth of solar photovoltaics (PV) needed for global climate goals has intensified focus on the upstream critical mineral supply chains enabling this technology. This paper synthesizes recent findings on the greenhouse gas (GHG) emissions associated with key minerals used in PV systems – notably silicon, copper, lithium, and cobalt – and the strategies to decarbonize these supply chains. Life-cycle assessments and supply-chain analyses reveal that mining, processing, and refining of these minerals can contribute significantly to the embodied emissions of PV installations, with hotspots in energy-intensive stages like polysilicon refining, copper smelting, and battery metal production. Emissions vary widely by region depending on the energy mix and production practices, highlighting opportunities for supply chain optimization. We discuss mitigation options including renewable-powered mineral processing, electrification of mining equipment, energy efficiency, recycling, and alternative materials, alongside emerging policy frameworks (e.g. EU Critical Raw Materials Act, international due diligence regimes) aimed at aligning mineral supply chains with climate targets. The literature indicates that a combination of technological improvements and policy interventions could substantially reduce upstream emissions (by ~30–40% in many cases) and enhance supply security. Ensuring the sustainability of critical mineral supply chains is imperative for PV to deliver on its promise of truly clean energy.