Proceeding from the accommodating capability of renewable energy，some key factors that affect low-carbon benefits resulting from renewable energy integration are analyzed，and an index of curtailment rate of renewable energy is utilized to measure low-carbon benefits.Based on this，an annual sequence production simulation model with large-scale wind power and photovoltaic（PV）power is proposed，which takes into account wind power and PV power output characteristics，load characteristics，load regulation characteristics of units，thermoelectric coupling characteristics of heating units，transmission capacity and some other factors.This mixed integer programming model is solved by the branch and bound method.With a certain provincial power grid as an example，the factors influencing grid low-carbon economy are quantitatively analyzed.The rationality of the model proposed and the correctness of theoretical analysis are verified by the results of calculation，which is of great guiding significance to electrical source planning and the formulation of relevant government policies required by low-carbon economy.