Capacity planning for wind, solar, thermal and energy storage in power generation systems considering coupled electricity-carbon markets

The development of the carbon market is a strategic approach to promoting carbon emission restrictions and the growth of renewable energy. As the development of new hybrid power generation systems (HPGS) integrating wind, solar, and energy storage progresses, a significant challenge arises: how to incorporate the electricity-carbon market mechanism into the planning of power system capacity. To address this challenge, this article proposes a coupled electricity-carbon market and wind-solar-storage complementary hybrid power generation system model, aiming to maximize energy complementarity benefits and economic efficiency. The model employs a bi-level optimization method based on the Improved Coati Optimization Algorithm (ICOA) to optimize the system's capacity planning. Simulations reveal that under the coupled electricity-carbon market scenario, renewable energy capacity increases by 23% over a 5-year planning period. Additionally, in this scenario, the total cost is 0.042% lower compared to the scenario without coupling. Under the constraint of a 30% renewable energy penetration rate, the capacity development of wind, solar, and storage surpasses thermal power, while demonstrating favourable total cost performance and the comprehensive complementarity index for HPGS. This model offers decision-making support for optimizing energy resource allocation and improving system reliability and economic viability.