Uncertainty-Based Dynamic Reserves and Flexibility Estimation

As solar and wind power become more common, power system operators and flexible resources must manage challenging imbalances induced by uncertainty. NREL researchers are studying solutions to mitigate or manage these imbalances.

Researchers discuss a power system model.


  • Data analytics for estimating the flexibility distributed energy resources can provide
  • Simulations using the Flexible Energy Scheduling Tool for Integrating Variable Generation (FESTIV)—a multiple-timescale simulation tool that includes security-constrained unit commitment, security-constrained economic dispatch, and automatic generation control—for estimating the value of more accurate reserve requirements and understanding the impact of modifications to power system operations and markets on the economic and reliability performance of the power systems
  • Decision analysis to assess different participation models in electricity markets for hybrid power plants and estimate the value of uncertainty mitigation and flexibility a hybrid power plant can achieve.


In this 3-year project, NREL researchers are studying how probabilistic solar irradiation forecast can inform the sizing of flexible ramping product requirements. The project advances the state of the art by using probabilistic solar forecasts to estimate flexible ramping product requirements. NREL is conducting simulations using FESTIV to estimate how system costs and reliability change when novel methods for estimating flexible ramping product requirement replace status-quo methods that rely on historical information overlooking the weather conditions.
In this 3-year project, an NREL-led project team is developing an operating paradigm that leverages flexibility from distributed and bulk resources to cost-effectively manage delivery risk of intermittent resources such as solar and wind. The project team is developing distributed energy resource flexibility scores that will recognize heterogeneity of distributed energy resources and inform the bidding and scheduling strategies of aggregators and utilities. NREL is also designing a flexibility auction that allows participants with uncertain output to hedge by buying physical flexibility from bulk supply resources and portfolios of distributed energy resources. The project aims to increase market surplus, improve power system reliability, and provide effective price signals.


Flexibility Auctions: A Framework for Managing Imbalance Risk, Federal Energy Regulatory Commission Technical Conference on Increasing Real-Time and Day-Ahead Market Efficiency Through Improved Software (2021)

What Is the Value of Alternative Methods for Estimating Ramping Needs?, IEEE Green Technologies Conference (2020)


Rui Yang

Group Research Manager II, Electrical Engineering