Policy System Coherence in China’s Provincial Hydrogen Industry: A Text-Based Evaluation of Themes, Instruments, and Structural Coordination

Hydrogen has become a strategic component of the energy transition and decarbonization. In China, province-level administrative regions have issued many hydrogen-related policies, but existing research has paid limited attention to how these policy texts are organized into coherent policy systems. This study evaluates the text-based structural coherence, design completeness, and textual coordination of China’s provincial hydrogen industry policies. Using 315 hydrogen industry policy documents issued across 31 province-level administrative regions, it constructs a “themes–instruments–text-based coherence” analytical framework that integrates the latent Dirichlet allocation topic model, content analysis, and the policy modeling consistency index model. The results show that China’s provincial hydrogen industry policy systems contain five themes: hydrogen industry development, technological innovation, policy support, industry regulation, and operational management. The thematic structure is strongly oriented toward industrial development and technological innovation. The policy instrument analysis indicates that capacity-building instruments dominate the instrument configuration, accounting for 55.87%, while instruments related to government demand, institutional supply, and safety regulation are less prominently represented. The PMC-based evaluation shows that the average text-level coherence score is 6.75, indicating a generally good level of structural coverage and design completeness as reflected in policy texts, but with regional and dimensional differences. Issuing levels constitute the weakest textual dimension, while thematic coverage and instrument configuration show room for improvement, suggesting less systematic textual representation of vertical linkage and uneven instrument complementarity. This study contributes to hydrogen policy research by shifting the analytical focus from individual policy documents to provincial policy systems and by clarifying how policy themes, instruments, administrative arrangements, governance levels, and temporal structures shape the structural coverage and design completeness of hydrogen industry policy at the textual design level.