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The Flexible Energy Scheduling Tool for Integration of Variable Generation (FESTIV) is a model that simulates the behavior of the electric power system to help researchers understand the impacts of variability and uncertainty on operating reserves requirements. FESTIV includes security-constrained unit commitment, security-constrained economic dispatch, and automatic generation control sub-models.

Electric power system operators use a variety of scheduling techniques to match electricity generation and demand. When the total supply of energy is different from the total demand, system operators must deploy operating reserves (including regulating, following, contingency, and ramping reserves) to correct the energy imbalance. The way they do this and, especially, the way they plan for this can affect the reliability and efficiency of the power system—particularly if it includes large amounts of variable generation.

Electric power system operators have established rules and practices based on a long history of traditional operations. However, many systems are exploring new ways to operate with high penetrations of variable generation. Renewable integration studies are assessing the impacts of high penetrations of variable generation on electric power systems and identifying alternative approaches for allocating and deploying operating reserves.

NREL is collaborating with the Midwest Independent Transmission System Operator and the Western Electricity Coordinating Council to understand how the variability and uncertainty of variable generation impact operating reserves. High penetrations of variable generation may require adjustments to the amount of reserves, the types of reserves, and how reserves are deployed.

For More Information

For more information about FESTIV and the impact of variable generation on operating reserves, see the following resources. Additional publications can be found in the NREL Publications Database.


Erik Ela