Power capacity optimization and long-term planning for a multi-energy complementary base towards carbon neutrality

To achieve its carbon neutrality commitment by 2060, China is actively promoting wind and solar power generation. However, the inherent randomness, fluctuation, and intermittency of these renewable sources pose significant challenges to grid stability and complicate the matching of electricity supply with load demand. Large-scale multi-energy complementary bases, integrating thermal power generation and energy storage, represent a viable approach to mitigate the instability of renewables. Optimal planning and capacity configuration for such bases can enhance energy utilization efficiency while adhering to carbon emission constraints. This study presents a methodology for optimizing the long-term capacity configuration of large-scale multi-energy complementary bases, by synthesizing the objectives of cost, carbon emissions, and electric source-load deviation. The methodology is applied to a multi-energy complementary base integrating renewables, thermal powper and energy storage battery. Through the comparison of long-term planning scenarios, the wind-photovoltaic-thermal-battery system integrated with Carbon Capture, Utilization, and Storage (CCUS) proved optimal, demonstrating lower costs and reduced source-load deviation. Over the 30-year planning horizon, the installed capacities of wind power, photovoltaic power, and battery storage are projected to increase by 1.93, 5.86, and 11.77 times, respectively, with a maximum source-load deviation of 8.9 %. Operating characteristic analysis revealed that thermal power plays a critical role in peak load regulation in 2030 within the optimal system. However, its sufficiency diminishes approaching 2060. This optimal planning scheme provides valuable insights for policymakers when formulating low-carbon energy strategies.