A stock-based framework for monitoring fossil persistence and renewable expansion in global power systems

Rapid renewable capacity additions are widely interpreted as evidence of power-sector decarbonization, yet observable renewable growth frequently coexists with fossil persistence. For climate mitigation governance, transition monitoring must distinguish between capacity additions and physical asset displacement. Using unit-level asset data from the Global Integrated Power Tracker (2010–2026), we develop an auditable, stock-based monitoring framework for characterizing the operating-stock dimension of the global power transition. By explicitly separating realized changes in operating assets from forward-looking pipeline orientation, we show that these dimensions often diverge. Although global development pipelines are broadly renewable-tilted (median renewable pipeline share = 0.828), realized stock reallocation remains sharply polarized across subregions. Fossil persistence remains widespread even under substantial renewable expansion: among subregions with net positive stock reallocation, 12 of 14 remain expansion-led, and among the highest-ranking subregions on this stock-based measure, 80% exhibit renewable additions layered onto a non-contracting fossil asset base. These findings show that tracking renewable additions alone is insufficient for monitoring stock-level transition progress. The framework is intended to diagnose structural change in the operating asset base rather than generation displacement or emissions reduction directly. Credible climate mitigation governance therefore requires a diagnostic approach that separately tracks renewable build-out, fossil operating-stock persistence, and pipeline orientation, while strengthening retirement transparency as a core component of phase-out monitoring.