“…Of course, that impact will be higher as wind penetration grows. Independent System Operators (ISO) can take different general approaches to accommodate the additional uncertainty at the unit commitment level, such as improving forecasting models for the wind (Mahoney et al, 2012), adjusting reserve requirements for the system (NERC, 2010;Ortega-Vazquez & Kirschen, 2009;Wang & Hedman, 2015;Luna-Ramírez, Torres-Sánchez, & Pavas-Martínez, 2015), implementing stochastic unit commitment (Ruiz, Philbrick, Zak, Cheung, & Sauer, 2009;Papavasiliou, Oren, & O'Neill, 2011;Holttinen et al, 2012), and/or using a rolling-planning scheme (Tuohy, Meibom, Denny, & O'Malley, 2009). Thus, among the ancillary services needing revision as wind prominence grows are operational reserves, that is, the extra generation capacity put online in the day-ahead unit commitment.…”