Multi-stage stochastic planning for a long-term low-carbon transition of island power system considering carbon price uncertainty and offshore wind power.

The characteristics of isolated grids lead island power systems to rely on stable conventional generation, which is not environmentally friendly and has high carbon emissions. This paper proposes a low-carbon transition model for island power systems considering large-scale offshore wind resources and the long-term uncertainty of carbon prices. First, a detailed model for offshore wind power systems is proposed considering the interaction of multiple wind farms and three transmission technologies. Second, a multi-stage power system planning model is established including the upgrading and decommissioning of thermal units. Meanwhile, an improved long-term carbon price uncertainty modeling method based on the binomial tree is proposed. Then, focusing on the uncertainty of carbon prices, a multi-stage stochastic optimization model is established, and the stochastic nested decomposition algorithm is used to solve the problem. Finally, numerical results show that the low-carbon transition develops plenty of offshore wind power as the primary power source and usually adopts a fractional frequency transmission system for offshore wind integration. The uncertainty of carbon prices has a significant impact on the transition: in the high carbon price realization, the annual carbon emissions are only 0.088 Mt, while in the low carbon price realization, the annual emissions are 0.255 Mt. • Low-carbon transition is modeled via multi-stage programming and solved by SND. • Improved binomial tree model for long-term carbon price uncertainty is proposed. • Detailed planning model of offshore wind systems is established. • Wake effect between wind farms are considered and linearized by wake factors. • Fractional frequency transmission system is adopted and analyzed. [ABSTRACT FROM AUTHOR]