Review Of Operating Reserves And Day-Ahead Unit Commitment Considering Variable Renewable Energies: International Experience

The steady growth of wind power generation has produced that the system operators have to face more challenges to keep their operations safe all the time. The quantification of operational reserves takes a very important role because this type of reserves corresponds to the generation capacity, and other resources, that are ready to respond in case of contingency. This paper presents a review of operating reserves used in electric systems to compensate the fluctuations in load and generation, and maintain the equilibrium between supply and demand. The present study includes a review of: (1) the concept of operating reserves, (2) the methods used by markets around the world to include the assessment of operating reserves in the Day-Ahead Unit Commitment process. The purpose of this study is to compare the different methodologies used in electricity markets around the world to model the quantification of operating reserves requirements. The main conclusion found is that deterministic quantification of the operating reserves evaluated on many stochastic scenarios is the most common approach because it increases the accuracy of the solutions found when compare to the use of the central forecast. Moreover, the markets are expanding the type of resources than can provide operating reserves including demand side response.