Although there have been many advances in PCM techniques over the past decade, the representation of hydropower operations has remained relatively rudimentary. Hydropower operational constraints (e.g., equipment, water use priorities and rules, environmental constraints) are not easily characterized in unit commitment and economic dispatch models. Uncertainties involved with hydropower planning also do not align well with grid operation methodologies. These misalignments make it difficult for grid operations models to comprehensively value and make the best use of the flexibility available with hydropower generation. To address these challenges, NREL will lead integration of intraday and day-ahead grid operations models with a river basin model, enabling a global optimization across both grid and reservoir operations. The lab will also use stochastic hydropower forecasts combined with progressive hedging to perform multi-stage, multi-time period optimization. This allows the combined grid and water model to value multiple timescales and uncertainties in a single optimization, enabling more accurate value of real-time flexibility to help balance supply and demand under different scenarios while enforcing precise, long-term water level constraints. In essence, the project will help to improve both grid and water system resilience while making better use of the water throughout the season.
