Navigating optimal solar-wind trade-offs under climate change

The optimal solar-wind ratio (SWR) plays a critical role in shaping the cost and reliability of renewable electricity systems, yet its adaptability under climate change remains poorly understood. Here, we develop a climate-driven SWR optimization framework that couples multi-model climate projections with an integrated investment and dispatch model to quantify how future climate variability reshapes cost-optimal solar-wind configurations. We find that optimal SWRs exhibit pronounced latitudinal differences and show modest changes under climate change. Deployment pathways inherited from the historical preference scenario may diverge from optimal SWRs, leading to increases in system costs and capacity requirements. In many regions, these SWR mismatches amplify electricity supply costs far more than the cost impacts associated with climate-induced changes in renewable resources alone. Cost escalation is driven mainly by SWR mismatch rather than solely by climate-induced resource changes. These findings highlight the importance of climate-responsive and region-specific SWR optimization as a key element of resilient and economically efficient power system planning. This study finds that climate change modestly alters optimal solar-wind ratios, whereas deployment pathways that diverge from climate-consistent optimal ratios can substantially increase electricity supply costs and capacity needs across regions.