An evaluation of High Temperature Low Sag conductors for uprating the 220kV transmission network in Ireland

A study carried out by ESB International has demonstrated that a requirement to provide significant rating increases on some 800km of the existing 220kV network can only feasibly be met through the use of High Temperature Low Sag (HTLS) conductors. Five HTLS conductor types were considered, three conventional core designs, namely ACSS, GTACSR and TACIR and two composite core designs, ACCC and ACCR. The remit of the study was to evaluate HTLS conductor types by three criteria; technical merit, economic advantage, and acceptable risk, and to establish which of these conductors would be suitable for use on the 220kV network. Following this investigation, it was recommended that GTACSR conductors be used for the uprating.