© 2021 IEEE.Increasing renewable energy sources capacity in power systems brings many problems. One of them is grid flexibility. The flexibility of a grid is directly proportional to the balance between demand and supply and this balance is determined by the deviations in the frequency of the grid. Therefore, in this study, an examination and analysis have been made to improve the flexibility of the grid. In this study, ancillary services using battery systems and demand response are discussed and analyzed its suitability for frequency support. Battery energy systems and demand response controls are effective methods to balance power generation and load demand, as they have a fast response feature. This analysis is made with the Powerfactory program, which provides engineering services in the field of electrical power systems for transmission, distribution, and industrial facilities.