Regional electricity distributor Ergon Energy is currently engaged in two significant infrastructure projects aiming to improve reliability and underpin growth in Queensland’s Darling Downs.
In Toowoomba’s CBD a $70million, three-storey substation designed to blend with a nearby shopping centre is taking shape.
Further south in Warwick, constructing a new substation within the footprint of the existing one without interruption of supply to around 5,000 customers will be the challenge for Ergon Energy’s Major Projects team over the next 18 months.
Ergon’s Major Projects General Manager, Brian Iwaszczyn, said that, when completed, the infrastructure will underpin future growth in the two population centres and provide a reliable electricity supply for years to come.
Toowoomba’s three-storey indoor central substation is part of a more than $70million program of work and will incorporate new technologies including gas-insulated switchgear (which saves significant amounts of space compared with air insulated equipment).
The project also involves an upgrade at the nearby South Toowoomba substation, including gas-insulated switchgear technology and dual-circuit 110kV underground cables between the two subs to provide a higher level of reliability and security of supply for 24,000 customers.
A key component of the south Toowoomba site – an 18m-long, 70-tonne modular building with concrete base technology – was built at Ergon’s manufacturing facility in Brisbane and transported to the site in August.
“The Queensland Investment Corporation began development of the central Toowoomba site in late April this year, with QIC project manager Savills engaging civil contractors Kane Constructions,” Mr Iwaszczyn said.
Handover to Ergon Energy for the next stage – electrical fit-out – was planned to commence in November.
Mr Iwaszczyn said the substation will service the growing Gardentown Shopping Centre redevelopment, due to open in 2016, and underpin growth in the city’s central business district for decades to come.
While smaller in scale, the Warwick project calls for another focus.
“East Warwick substation has served the community well, however a modern replacement was clearly needed to meet future requirements,” Mr Iwaszczyn said.
“The challenge at this site is maintaining supply as we build a new sub in the footprint of the old East Warwick sub by late 2015.”
Transformer capacity will increase from 20MVA to 50MVA, meaning the new transformers will be able to meet future demand on the network and enable some load that has been temporarily transferred to West Warwick substation to be returned.
“The East Warwick sub will be rebuilt in three stages to ensure continuity of power supply while the work proceeds,” Mr Iwaszczyn said.
Stage one, slated for completion by February 2015, will see the installation of a new 25MVA transformer and modular building which will allow load transfer from the existing substation to the new equipment.
The second stage involves the de-energisation and demolition of the former substation.
The third stage will be the construction of the remaining new substation plant such as the second transformer and modular building, NER’s, capacitor banks, station services transformers, fence and driveway.
While the existing substation is built outdoors, the revamped version will feature two modular buildings to house new switchgear. Ergon Energy will again manufacture the two modular substation buildings at its facility at Banyo on Brisbane’s north side before transporting them 170km to Warwick site as complete units. The factory-built solutions – designed and built to align with the equipment lifecycles – will be fully functional and incorporate switchgear and associated panel wiring.
Tenix, the principal contractor onsite, began work at the East Warwick site in mid-July.
Mr Iwaszczyn said the modules from Brisbane would go a long way to improve the visual aesthetic of the site for nearby residents.
“The West Warwick substation has recently been upgraded, and work is also under way to upgrade the Warwick bulk supply substation. Meanwhile the high-voltage lines between the substations have also been replaced,” Mr Iwaszczyn said.
“Almost a decade ago, this was one of the worst-performing parts of our network, but since then we have refurbished a sub-transmission line from Toowoomba to Warwick and rebuilt the second one as a new, high-reliability line.
“When the work at East Warwick and the bulk supply substation has been completed, the Warwick community can be confident of having a safe and reliable power supply for years to come.”
Completion of the Toowoomba and Warwick projects will be two milestones for Ergon’s significant refurbishment program to key electricity network infrastructure on the Darling Downs.
A multi-million dollar improvement program has seen improved network reliability to customers in Dalby, Stanthorpe, and Miles, as well as Waroo, Coomrinth, and Sandy Creek areas in Queensland.