Quantifying the roles of policy and technology on China's hydrogen-electricity integration: A multi-scenario analysis of cost and decarbonization dynamics

Amid accelerating global deep decarbonization, hydrogen is a key option for addressing hard-to-abate emissions, and electricity-hydrogen synergy is central to achieving carbon neutrality. Under carbon constraints and uncertain hydrogen demand, this study develops a China Electricity-Hydrogen Synergy TIMES model with multidimensional scenarios to explore cost-optimal decarbonization pathways driven by policy and technological progress. The results show that external interventions are critical for achieving deep decarbonization. Under the Baseline Scenario, gray hydrogen will remain above 47% of total hydrogen supply by 2060, while policy intervention can accelerate the dominance of green hydrogen to around 2045, and technological breakthroughs will enable green hydrogen to completely replace gray hydrogen before 2040. By 2060, electricity demand for hydrogen production will account for 18.9%-34.6% of total power generation and drive a 16.7%-27.0% increase in wind and solar capacity under stronger intervention scenarios. Policy intervention can accelerate the achievement of green-gray hydrogen cost parity by 5-10 years, while electrolyzer learning rates and renewable power costs are the dominant drivers of green hydrogen competitiveness.