A Systemic Evaluation of Energy Digital Transformation Policies for the G20 Group of Countries: A Four-Dimensional Framework and Cross-National Quantitative Analysis

The global integration of digital technologies into energy systems constitutes a critical pathway for achieving sustainable and intelligent energy governance. This study evaluates the effectiveness of the energy digital transformation policies across eighteen major economies through a comprehensive four-dimensional framework, which encompasses policy objectives, intensity, instruments, and stakeholder engagement. Through the application of the entropy-weighted TOPSIS method, our comparative analysis identifies a distinct hierarchy in national policy performance. The first tier, including the United Kingdom, the United States, South Korea, Australia, China, and Germany, demonstrates high coherence, enforceable mechanisms, and multi-actor coordination. The second tier, comprising Saudi Arabia, France, Turkey, Russia, Canada, and India, exhibits partial alignment with notable strengths in selected dimensions yet significant gaps in enforceability or stakeholder integration. The third tier, featuring Italy, Brazil, Argentina, Mexico, Japan, and Indonesia, is characterized by fragmented approaches and aspirational goals lacking implementation specificity. Stakeholder inclusiveness emerges as the most influential dimension, accounting for 38.3% of total weighting and substantially accounting for variations in efficacy. Moreover, nonlinear threshold effects are identified, indicating that subcritical performance in any dimension leads to disproportionate declines in overall outcomes. These findings underscore that synergistic policy design, which entails balancing objectives, governance capacity, instruments, and actors, is indispensable for effective energy digitalization.