Hybrid-LCA-based carbon emissions of 750 kV substation in arid sandy land: a case study of Qinchuan substation in Northwest China

Substation construction in arid sandy areas involves intensive consumption of carbon-intensive materials, contributing to significant carbon emissions and environmental pressures. Taking the Qinchuan 750 kV substation in Northwest China's arid sandy region as a case study, this study employs a Process-Input-Output (Process-IO) Hybrid Life Cycle Assessment (Hybrid-LCA) model to quantify the whole life cycle carbon emissions of the substation. It further uses Monte Carlo simulation to analyze uncertainties in the life cycle carbon emission assessment and proposes targeted carbon neutrality pathways based on deterministic emission analysis results. The findings reveal that: (1) Indirect carbon emissions during the operational use (OU) stage account for 90.93% of total life cycle emissions, followed by the material production (MP) stage at 8.22%. (2) Monte Carlo simulation (10,000 iterations via MATLAB R2024a) for the average life cycle yields a 90% confidence interval of (9,675, 11,775) kg. (3) Specific carbon neutrality pathways are proposed: extending the substation's lifespan by 90% to reduce emissions by 4.8×10 6 kg; promoting low-carbon materials ( e.g. , timber substitution reduces emissions by 3.4×10 6 kg); increasing grid renewable energy to 30% by 2035 to cut operational emissions by 18.5%; and deploying photovoltaic technology to achieve annual carbon reduction of 49,400 kg, contributing to carbon neutrality.