Economic and Operational Assessment of Reserve Methods and Metrics for Electric Grids With High Shares of Renewables

This study is based on the recent development of the European energy environment, which experiences a transition from being dominated by conventional energy generation into an increased penetration of renewable energy sources. Today's system operators offer a set of ancillary services, such as control reserves, which cover mismatches of energy demand and supply. However, higher reserve volumes also lead to increased procurement costs. In this study, three reserve-dimensioning methodologies are assessed with regard to their stability and cost metrics. For the calculations, an updated version of the IEEE 24-bus RTS is generated. Each method is being applied to three grid cases, which reflect a conservatively low renewable energies scenario, a high share of wind energy scenario, and a high share of mixed renewable energies scenario, respectively. The results show the trade-off between reliability and costs for each of the three scenarios evaluated