From polysilicon to modules: Energy leakage in global PV trade and pathways to decarbonization

The rapid expansion of global PV trade is accompanied by a notable “energy leakage” effect, where energy-intensive production processes are relocated via international trade to regions with lower energy efficiency, thereby undermining the overall emission reduction potential of the PV industry. This study integrates life-cycle data of PV products from 139 countries and constructs a multi-regional model based on 2021 actual trade flows, uncovering the embodied energy transfer characteristics across the entire supply chain from silicon feedstock, wafers to modules. The results reveal a profound fossil energy dependence (91.3–92.69%) throughout the supply chain. While current trade patterns enhance local energy efficiency through specialization, regional electricity mix disparities and cross-border transportation result in a net increase of 347.6 billion MJ energy input in the global supply chain, creating a vicious cycle of “scale expansion–energy leakage escalation”. Policy interventions show divergent effects: carbon tariffs and geopolitical conflicts reduce energy leakage through regionalized production reshoring at the cost of $2.3 billion trade losses, whereas technological breakthroughs achieve a win-win of “scale expansion and energy consumption reduction” (cutting 12.8 billion MJ fossil energy input). The study proposes a clean transition pathway leveraging process-specific differentiation and regional synergy to resolve the energy-environment paradox in PV trade.