Economic and Operational Characteristics of PWR Unit Participation in Grid Peak-Load Regulation

Abstract

Following the unceasing changes in power demand and the power utility structure in China, the load fluctuation characteristics of the power grid are gradually increasing. The capacity of the power grid’s peak-load regulation and transmission has become the bottleneck of nuclear power and intermittent renewable energy consumption. In some jurisdictions of China, the curtailment of the wind and solar power output is higher than 30%, and the unplanned halt of nuclear power plant operation happens periodically. These phenomena cause energy efficiency decreases and potential safety hazards for nuclear power generation units. How to increase the “flexibility” of the power system has become a main issue of China’s power grid that can contribute to the promotion of nuclear power plants’ production and reduce the curtailment of wind and solar energy. Based on China’s power grid structure, the power plants’ geographical distribution, the power plants’ operation characters, the power grid load characteristics, and the power grid operation modes, the performances of various types of power sources participating in daily load regulation are compared, including the peak-load regulation capacity, response characteristics, environmental benefits and economic benefits. On account of the above outcome, drawing on the experience of international research results and based on a feasible power plant’s load characteristics and operation economy, a strategy of power plants participating in peak-load regulation is proposed, and an evaluation index system is built. The strategy and index are both used to elevate the power grid’s power quality and operation economy, optimize the multi-energy coupling power supply model, and evaluate the PWR units’ core competence. A peak-load regulation strategy and policy proposal is concluded in the treatise.