Power system planning, operation, and operational planning methods have evolved over the years to economically supply reliable power to customers. Emerging environmental compliance requirements have dictated needs to develop methods to manage increased uncertainties associated with renewable resources. These new challenges are increasing problems in operational planning, as existing deterministic procedures cannot comprehend these uncertainties to provide suitable indicators in decision making. Uniformity in operational adequacy evaluation methods and quantitative metrics applicable to all power systems is desirable. However, various utilities and independent system operators (ISOs) have their own practices and methodologies to address their unique needs. This paper presents a review of operational planning practices in different ISOs and utilities based on planning-horizon length, granularity, and reliability metrics. The challenges and deficiencies in existing operational planning practices and regulations are identified. Finally, features necessary to maintain the uniformity in operational planning while fulfilling operational adequacy requirements are recommended.
