Co-Benefits of Solar PV Expansion and CCUS Deployment for Carbon and Air-Pollutant Reduction in Guangxi’s Power System: A LEAP-Based Scenario Analysis to 2060

Provincial power systems must decarbonize while sustaining rapid demand growth and improving air quality; yet, few integrated assessments separate the contributions of renewable expansion and carbon capture, utilization, and storage (CCUS) for China’s less-developed regions. We apply the Low Emissions Analysis Platform (LEAP) to model Guangxi’s power system to 2060 under four scenarios—Reference (BAS), Renewable-driven (RES), CCUS-intensive (CCS), and an Integrated comprehensive-policy scenario (ICS). Under ICS, solar photovoltaic generation rises from 38 TWh in 2025 to 408 TWh in 2060 (close to half of all generations), non-fossil capacity grows by about 730%, and power-sector CO2 falls by roughly 95% relative to BAS. A counterfactual decomposition shows that CCUS provides about 75% of the CO2 reduction along the coal-retaining CCS pathway but only about 5% along the renewables-led ICS pathway and reduces neither SO2 nor NOx. The air-quality co-benefits—up to 82%, 78%, and 73% lower SO2, NOx, and PM2.5 than BAS—arise mainly from renewable substitution, which also abates carbon more cheaply (about 120–190 versus 300 CNY t−1 CO2) while sharply raising flexibility needs. Once avoided fuel and carbon-market costs are included, the renewables-led pathways become net cost-saving on a full-system basis and yield a monetized air-quality health co-benefit roughly twice that of the CCUS-intensive route. The findings give policy-relevant guidance for sustainable low-carbon transitions in Guangxi and comparable emerging regions.