To vigorously develop new energy is an imperative for advancing China's energy reform and realizing the transformation of its energy structure, and it has important strategic significance. This paper evaluates the ability of the grid to accept new energy sources at different time scales from the perspective of long-term peaking and short-term operation. Starting from the long-term time scale, considering the evaluation of the new energy absorption capacity of the peak-constraint constraints, taking into account the constraints of the power supply structure, the regulation characteristics of the conventional units, the tie-line plan, and the load characteristics, the new energy acceptance capability was evaluated.