Technology Interactions Cut China's Coal Decarbonization Costs, Enabling 1.2 Gt Negative-Cost Mitigation

The arXiv preprint develops an interaction-aware framework that simultaneously optimizes three retrofit pathways while constraining shared biomass supply and CO2 storage. Plant-level heterogeneity in age, efficiency and location drives different optimal portfolios: early plants favor conservation, mid-age units adopt biomass, and newer units add capture. Accounting for synergies and competition alters both individual technology costs and fleet-wide marginal abatement curves.

This shifts the cost-optimal sequence from isolated measures toward staged deployment ending in biomass-plus-capture for net-negative emissions. The result directly informs China's 2030-2060 targets and global coal-retrofit strategies by showing that ignoring interactions overstates required carbon prices. Infrastructure planning for biomass logistics and storage hubs becomes the binding constraint rather than plant-level economics alone.

Related IEA and IPCC analyses reach similar conclusions on retrofit sequencing but lack the plant-resolution interaction modeling performed here. The preprint's shared-resource constraints highlight supply-chain bottlenecks that single-technology studies routinely omit. Coordinated policy on biomass certification and CO2 transport networks will determine whether the modeled negative-cost potential materializes.

Next steps include coupling the framework with dynamic biomass yield projections and testing sensitivity to storage capacity estimates under China's announced CCUS clusters.