Powerlink has recently published a 'Project Assessment Conclusions Report' to address the power transfer and reliability of supply risks at Bouldercombe Substation.
Located approximately 19 kilometres south-west of Rockhampton and established in 1975, Bouldercombe Substation is a major transmission node for Central Queensland, marshalling a number of 275kV circuits from Nebo and Broadsound to the north, Stanwell in the west and Raglan and Calliope River to the south. It also provides the sole 132kV injection source for the area, supplying Ergon Energy at Rockhampton, Egans Hill and Pandoin, as well as Stanwell Power Station's auxiliary supply and customers directly connected to Powerlink's network.
Transformers 1 and 2, along with the original circuit breakers, disconnectors, earth switches and instrument transformers at Bouldercombe Substation are nearing the end of their technical service lives, with manufacturers no longer providing technical support or carrying spares for many of the items.
The first step of the Regulatory Investment Test for Transmission (RIT-T) was the publication of the Project Specification Consultation Report (PSCR) in October 2018 which invited submissions particularly on the credible options which could address the identified need.
The proposed preferred option identified in the PSCR considered to satisfy the RIT-T involved the installation of a standard 250MVA transformer and the upfront replacement of all primary plant in selected bays by December 2021. There were no submissions received in response to the PSCR which closed on 25 January 2019.
The outcomes of the economic analysis contained in the PACR remain unchanged from those published in the PSCR. Consequently, the draft recommendation to install a standard 250MVA transformer and replace of all primary plant in selected bays by December 2021 has been adopted without change as the final recommendation in the PACR.
The estimated capital cost of this option is $30.6 million in 2018/19 prices. Powerlink is the proponent of the proposed network project.
In the context of engagement activities with consumers and the general community, Powerlink has assessed this project as 'minor' on the RIT-T Stakeholder Engagement Matrix.
A copy of the Project Assessment Conclusions Report is available below.