Balancing the output and quality of variable renewable energy generation in wide area based on multi-objective optimization

Abstract

To alleviate the pressure of excessive carbon emissions on the environment, the installed capacity of variable renewable energy represented by wind and solar energy has significantly increased. However, the strong volatility in high-capacity variable renewable energy may directly lead to high flexibility requirements, thereby endangering the reliability and economy of the power system, if no effective measures are taken. Expected high-quality energy has low flexibility requirements. This paper aims to achieve this goal based on the combination of wind and solar energy: at first, the indicators about the power out, flexibility requirements and comprehensive performance of variable renewable energy are respectively proposed. The characteristics of wind energy and solar energy are statistically analyzed based on the proposed indicators. Then, the paper proposes an allocation method for wind-solar energy ratios in wide area based on genetic algorithm. Single objective optimization and multi-objective optimization are conducted sequentially, with the eastern region in China as the site. Finally, the comprehensive performances of variable renewable energy before and after optimization are compared through statistical method. The results indicate that the proposed method can significantly improve the comprehensive performance and effectively balance the output and quality of renewable energy.