$158 million programme of regional upgrades
20 April 2005
$158 million programme of regional upgrades submitted to Electricity Commission
Transpower has sought Electricity Commission approval for a comprehensive programme of regional upgrades to the national electricity grid.
A number of the projects have been completed while others are in the planning stages. Electricity Commission approval will allow Transpower to recover the costs incurred through the Commission’s pricing mechanism.
Transpower Chief Executive Dr Ralph Craven says the regional upgrades submitted for Electricity Commission approval are among those identified in the document Future of the National Grid, published in December 2004.
“We have been communicating the need for these ‘tactical upgrades’ to customers and other stakeholders for the past two years. The most significant projects in terms of cost are those to deliver improved security of supply into Christchurch and the upper South Island.
“In terms of timing, the focus of these 30 projects is to address the short term issues that have already arisen or are likely to arise in the next two or three years. They do not address all the security issues forecast to occur over the next 10 years. In effect, they ‘buy us time’ for the major investments needed in the core electricity grid.
“All of these projects are aimed at extracting the maximum transmission capacity possible from Transpower’s existing assets,” Dr Craven said.
The projects fall within 5 broad categories.
Transmission Line Thermal Upgrades Using aerial laser surveying technology it has been possible to identify those transmission lines which can be ‘run hotter’, thus increasing their capacity.
Capacitor banks Capacitor banks installed at Transpower substations improve local voltage quality and reduce voltage instability.
Stringing additional circuits Two projects in the upper South Island: Islington-Kikiwa and Blenheim-Stoke, involve installing second circuits on tower lines that presently are only fully strung on one side. Easements are required to be purchased as part of these projects.
Installing additional Conductors (Duplexing) In Canterbury, the capacity of the Livingstone-Islington 220 kV line can be doubled by installing an additional set of conductors in parallel with the existing conductors.
Bussing circuits The ability to interconnect or “bus” long lines at a convenient mid-point provides a low cost way of reducing the impact of a line outage and increases the voltage stability of the overall system.
“The overall budgeted cost of the 30 projects presented to the Electricity Commission for approval is $158 million,” Dr Craven said. “This is the most significant investment in the national grid for many years.
“We expect the Electricity Commission to consider and approve these important projects under the appropriate provisions of the Electricity Governance Rules.”
The full submission to the Electricity Commission can be found at www.transpower.co.nz under asset owner publications.
For more information: Chris Roberts, Communications Manager, 021 534 010
REGION PROJECT COMmissioning
DATE BUDGET $
North Isthmus Henderson – Otahuhu 1 & 2 Thermal Upgrade April 2006 2.3 million
Auckland Otahuhu – Penrose 5 & 6 Thermal Upgrade 2006 700,000
Huntly – Otahuhu 1 Thermal Upgrade Completed 1.7 million
2 x 50 Mvar 110 kV Penrose Capacitors May 2006 2.4 million
1 x 50 Mvar 110 kV Hepburn Rd Capacitor May 2006 1.4 million
Bombay – Otahuhu 1 & 2 Thermal Upgrade May 2005 800,000
Waikato Hamilton – Waihou 1 & 2 Thermal Upgrade Completed 720,000
Bay of Plenty Tarukenga – Tauranga 1 Thermal Upgrade December 2005 250,000
Wairakei – Poihipi – Whakamaru 1 Thermal Upgrade Completed 1.65 million
Central North Island Tokaanu – Whakamaru 1 & 2 Thermal Upgrade April 2006 6.4 million
Rangipo – Wairakei 1 Thermal Upgrade April 2006 3.2 million
Bunnythorpe – Tokaanu 1 & 2 Thermal Upgrade April 2008 8.5 million
Wellington Bunnythorpe – Haywards 1 & 2 Thermal Upgrade April 2006 4.8 million
Nelson/ Marlborough 40 Mvar Stoke Capacitors Completed 1.45 million
Islington – Kikiwa third 220 kV circuit May 2006 32.5 million
New Culverden substation May 2006 5.0 million
New Waipara substation May 2006 7.2 million
Blenheim – Stoke 110 kV second circuit May 2006 20.2 million
West Coast Dobson – Inangahua line upgrade 66 kV to 110 kV August 2005 3.2 million
Second Dobson – Inangahua 110 kV circuit connection April 2007 265,000
Second Dobson interconnecting transformer April 2007 2.7 million
Canterbury 2 x 60 Mvar 220 kV Islington Capacitors April 2005 3.1 million
Islington – Livingstone 1 Thermal Upgrade Completed 1.6 million
Islington – Tekapo B – Twizel Thermal Upgrade December 2005 3.8 million
Islington – Timaru – Twizel 1 & 2 Thermal Upgrade December 2005 3.8 million
38 Mvar 66 kV Southbrook Capacitor December 2006 1.2 million
Islington- Livingstone 1 Duplexing May 2007 25.8 million
Bussing of Islington – Twizel A at Ashburton May 2008 7.3 million
South Canterbury Timaru – Temuka 1 & 2 Thermal Upgrade August 2005 500,000
Otago/ Southland Invercargill – Roxburgh 1 & 2 Thermal Upgrade Completed 3.8 million
Total 158.235 million