Determining the technical and economic impact of reconfiguring a transmission system

Evolution of the power system has left many older transmission lines in service. These transmission lines are increasingly expensive to maintain. Since these lines were originally built, additional new transmission lines have been built with capacity for forecasted future requirements. If these newer lines are used and the older lines decommissioned, the transmission capacity would be more fully utilized and maintenance expenditure would drop. Re-routing of power flows and retiring of old lines is to be optimized with further development of the network. Re-routing of power flows has an impact on the wider system. Services provided by generation connected to older lines may be reduced. This paper proposes a method of quantifying the technical and economic impact of re-routing the power flow while also addressing new and emerging issues in the network. As a case study the impact of decommissioning some older lines between a group of generators and a large load in Tasmania is analysed.