Flexibility resource and demand balance mechanism in power system planning considering high penetration of renewable energy

Abstract

High penetration of renewable energy is crucial to meeting future energy needs while decarbonizing and cleaning the electrical power system. In order to maintaining reliable and cost-effective operation while supporting high shares of variable renewable energy (VRE), adequate flexible resource are requested by both VRE and variable load (VL), and the basic balance mechanism between flexible resources and double variable sources become an extremely important issue. This paper introduced the mathematical description of power system flexibility “resource/demand” balance in planning stage based on probability theory. Then the evaluation indices of flexibility adequacy are proposed. A non-sequential probabilistic production simulation approach was applied to obtain the probability distribution function (PDF) of system operation status so that the PDF of flexibility resources and VRE/VL can be obtained. Finally, some numerical studies are conducted to verify the correctness and effectiveness of the proposed method and indices. The results shows that the indices can reflect the adequacy of system flexibility, which have strong correlation with the load shedding or new energy curtailment.