Reliability and life cycle cost estimates of 400 kV substation layouts

This paper presents an analysis of reliability and life cycle costs of two different schemes; a single busbar in two sections and a double circuit breaker system with double busbars. Two main questions initiated this study: (1) do the substations have a design of uniform strength regarding the reliability of included components and sub-systems or is there unnecessary redundancy or weak points? and (2) can improvements of reliability and availability of the components during the last decades be taken as a justification for simplification of substation schemes?