Against the backdrop of diversified hydrogen sources and the approaching "dual carbon" goals, a low-carbon optimization strategy that considers the synergy between electric thermal flexible loads and blue-green hy-drogen is proposed to reduce the system's carbon emissions, enhance the flexibility of hydrogen utilization, and improve the capacity for new energy consumption. First, the characteristics of blue hydrogen and green hydrogen are analyzed, and a production, storage, and utilization model for both is established. By analyzing carbon emissions and wind curtailment data under different green hydrogen proportion coefficients, the optimal proportion of green hydrogen is obtained. Secondly, transferable and substitutable load models are introduced on the load side, and satisfaction indicators for users and Electrolysis cell equipment are proposed to analyze the impact of flexible loads on the system's optimized operation. Finally, under the output con-straints of various equipment, a blue-green hydrogen economic low-carbon optimization scheduling model considering flexible loads is constructed with the goal of minimizing the system's total cost. The analysis of case results under four scenarios shows that the optimization model proposed in this paper reduces the system's carbon emissions, wind curtailment, and total cost by 52.85%, 26.22%, and 491.67 yuan, respec-tively. This proves the effectiveness of the method proposed in this paper.