Studying the Variability and Uncertainty Impacts of Variable Generation at Multiple Timescales

Abstract

With increasing levels of variable renewable energy, there is a growing need to study its impacts on power system operation. Variable generation (VG) is variable and uncertain at multiple timescales, and it is important that system operators understand how each of these characteristics impact their systems since each may have different mitigation strategies. To date, many of the studies of VG integration are limited to studying at one time resolution and therefore cannot analyze the variability and uncertainty impacts across multiple timescales. Here we study the variability and uncertainty impacts across multiple operational timescales. A model is used which integrates multiple scheduling sub-models with different update frequencies, time resolutions, and decision horizons. Using metrics that describe reliability and costs with a methodology that describes the sensitivities and tradeoffs of variability and uncertainty impacts separately with respect to the conditions that cause those impacts, case studies are performed which display greater information on expectations of these impacts on future systems with high penetrations of VG.