Development of transmission system reliability performance benchmarks

The reliability of an electric utility transmission system is a measure of its ability to continuously meet the demands of all its customers (i.e., points of delivery). Enhancing the supply reliability is one of planning and design targets of any utility within the constraints of capital investments, intense free-market competition, variable and higher level of customer preferences, and safety and environmental considerations. The utilization of transmission system facilities is changing from its traditional role in this new deregulated era and raising significant concerns about the possible erosion of the reliability of utility transmission facilities. It has been recognized that, with the movement toward a deregulated and competitive electricity market, decisions to improve reliability will be heavily influenced by industrial and commercial customer preferences requiring service level benchmarks to be defined. This paper presents an approach to establish realistic transmission system reliability performance benchmarks that provide a measure against which the different planning and design procedures can be evaluated to assist in achieving the primary objective of providing reliable electricity with competitive rates to utility customers.