As global digital transformation accelerates alongside the “dual carbon” goal, understanding how the digital economy can drive the green transformation of traditional energy systems is critical to overcoming resource and environmental constraints. This study examines the impact of digital economy attention on Green Total Factor Energy Efficiency (GTFEE) using panel data from 275 Chinese prefecture-level cities between 2011 and 2022. Three main findings emerged. First, an increase in attention to the digital economy significantly enhances GTFEE, serving as a key driver of improved energy efficiency. Specifically, a one-standard-deviation increase in attention raises GTFEE by 0.276 standard deviations. Second, this effect operates through two pathways: (1) digital technology advancements, such as higher internet penetration; (2) human capital accumulation, reflected in a greater college student ratio; and (3) green innovation, measured by a rise in green patents. Third, regional heterogeneity is evident, with stronger positive effects in eastern and coastal cities, while high-carbon-intensity regions exhibit a suppressed impact. These results underscore the importance of public engagement in digitalization to optimize energy systems. Policymakers should adopt region-specific strategies, such as boosting digital infrastructure in low-carbon areas and supporting structural reforms in high-carbon regions. This study expands our understanding of the digital economy’s role in enhancing energy efficiency and offers policy guidance for the green energy transition.