Abstract: With the continuous development of concentrating solar power (CSP) technology, how to reduce the adverse impact of auxiliary power load on the on-grid electricity of CSP units and further improve economic benefits has become a key focus in the industry. At present, in-depth research on the technical points of using photovoltaic-energy storage (PV-ESS) systems to supply auxiliary power for CSP plants is still lacking. Based on an in-depth analysis of the auxiliary power wiring scheme and load characteristics of tower-type CSP plants, this paper proposes a reasonable scheme for integrating PV-ESS systems into the auxiliary power system of CSP plants, establishes a capacity planning model for PV-ESS systems, and presents a solution method. The proposed scheme can increase the on-grid electricity and economic benefits of CSP plants, and provide a reference for similar projects.