Draft Grid Planning Assumptions (GPAs) released in May 2007 – interregional transmission analysis

The material on this page was developed and released for consultation in September 2006.  It is provided for information purposes only.

The Commission has completed a draft analysis of the cost to increase N-1 interregional transmission capacity in a number of increments. Those cost increments might typically involve an initial increase in thermal capacity of existing lines, followed by duplexing or re-conductoring, and finally the building of a new transmission line. This should enable participants and investors to independently analyse the interaction between transmission and generation investment on a regional basis. This is very similar to the approach adopted by Vencorp, who publish transmission enhancement costs curves for selected transmission corridors.

A draft of this analysis has been completed, drawing heavily on Transpower’s Annual Planning Report 2006 .  The System Studies Group (SSG) provided cost information on inter-regional transmission enhancements.

• SSG report on interregional transmission capacity pdf [480 KB]  (updated 11 May 2007)