Implementation of probabilistic methods for ranking transmission projects

A report by the Secretary of Energy´s Advisory Board (SEAB) on the reliability of the electric power system called for new probabilistic models, tools, and methodologies to accommodate uncertainty in planning and operations and recommended their use in optimizing the electrical system while maintaining requisite levels of reliability. It also recommended quantifying system health through numerical risk indices, such as the loss of load expectation or expected energy not supplied and rapid collection, analysis and distribution of data at major load delivery points as well as comprehensive monitoring of component performance to assess the causes of system reliability events. Entergy has been proactive in adopting and implementing methods that will help in using probabilistic methods in planning and operations of Entergy transmission system to supply quality power to its customers. While planning for Entergy´s long range transmission facilities, Entergy engineers follow certain operating guidelines which have been developed based on historical performance of Entergy system and its customer´s requirements. General Reliability has been working with Entergy in helping them to develop a framework for evaluating reliability of transmission facilities in a quantitative manner. This framework is used as a basis to rank transmission projects for increasing asset utilization and will be helpful in the decision making process. In this paper, authors present their preliminary investigations and experience with the proposed framework and present an actual case study to rank transmission projects. Further refinements and future enhancements to the proposed framework are also discussed.