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Graph of real-time balance of electrical supply and demand.

Real-time balance of electrical supply (generation) and demand (load).

Graph of distribution of electrical supply and demand mismatch.

Distribution of the mismatch between the electrical supply and demand (area control error, or ACE).

Graph of real-time prices as determined by FESTIV.

Real-time prices (locational marginal prices) as calculated by FESTIV.

The Flexible Energy Scheduling Tool for Integrating 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 power system operations. FESTIV includes security-constrained unit commitment, security-constrained economic dispatch, and automatic generation control sub-models.

FESTIV is a multiple-timescale, interconnected simulation tool. Each sub-model is connected to subsequent sub-models such that the output of one sub-model serves as the input to the next. FESTIV is completely configurable so that the effects of different operating temporal resolutions and operating strategies can be explored. FESTIV not only produces economic metrics but also produces reliability metrics. This enables FESTIV to fully investigate the trade-offs in economic benefits, reliability benefits, and incentive structures.

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. FESTIV allows researchers at NREL to explore different operating reserves strategies on system operations.

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

Ibrahim Krad