Renewable Generation Expansion Planning Considering Wind-Solar Spatiotemporal Complementarity under Climate Change

Rapid renewable expansion under climate change faces intensifying challenges from resource fluctuation and grid regulation pressure. This paper proposes a climate-adaptive coordinated planning strategy that leverages wind-solar spatiotemporal complementarity to mitigate these fluctuations. First, a seasonally dynamic Copula model identifies optimal complementary zones using ERA5-derived capacity factors, followed by a fluctuation-aware capacity ratio optimization to minimize net load variability. These pre-coordinated bases are then integrated into a two-stage stochastic planning model considering multiple CMIP6 climate scenarios. A case study in Shanxi, China, validates the methodology. Results demonstrate that compared to traditional resource-driven planning, the proposed strategy reduces energy storage capacity requirements by 28.9% and total annualized costs by 7.3%. Furthermore, the planned system maintains high reliability standards across diverse climate scenarios, confirming the system's robustness against long-term climate risks without excessive over-investment.