Challenges of energy transition in China's power system and its emission reduction impacts

China must accelerate its power system energy transition to meet the 14th and 15th Five-Year Plan targets. Our study reveals that, based on the trend during the 13th Five-Year Plan period, transitioning to wind and solar power would have greater challenges by 2030 compared to other energy sources, with southwest China, other regions, and old industrial base facing the most pressure. Under the enhanced policy scenario, the transition from 2023 to 2030 could reduce emissions of SO₂, NO_x, PM₁₀, and PM_2.5 by 49.3%, 34.6%, 37.8%, and 37.9%, respectively. Southwest China would lead in SO₂ reduction, while eastern coastal area would significantly mitigate NO_x emissions. For reductions in PM₁₀ and PM_2.5, the dominant contribution comes from eastern coastal area and energy-rich area. Our study underscores that a power system transition pathway tailored to regional conditions is essential.