TRANSGRID has responded to claims by community groups that the collapse of overhead transmission towers and the resulting blackouts in recent storms in Victoria highlight the danger inherent in overhead towers such as those planned for the Humelink project.
Transgrid says the infrastructure planned for the Humelink project would be able to easily withstand the force of storms such as those that hit in Victoria.
“Transgrid continually reviews its safety and design standards and we conduct regular maintenance programs to ensure our network remains safe and reliable as climate change impacts emerge,” a Transgrid spokesperson said.
“On our major projects, design teams consider existing and predicted climatic conditions when designing new assets.
“Transgrid’s network uses towers designed to withstand extreme weather conditions which exceed the weather conditions experienced in Victoria. The design of the 500kV assets in NSW meet the Australian Standard 7000 (AS7000) which enables towers to withstand higher wind pressure loading of up to 180km/hour. “
With regards to undergrounding, Transgrid says it conducted extensive investigations and has worked closely with landowners and local communities over the past two years to examine the feasibility of undergrounding HumeLink.
“Undergrounding high voltage transmission assets was considered and ruled out for HumeLink and VNI West due to multiple factors including the much greater cost of the delivery and maintenance of underground conductors to energy consumers, the lack of suitability of the technology to collect new renewable energy, the significantly shorter life span of the cables (up to 40 years) compared to towers (50 years), and the cost of delays to delivering this critical infrastructure. For example, undergrounding HumeLink would mean consumers will not have access to cheaper renewable energy for a further five years, at a cost of up to $1 billion for consumers.
*(Based on delay period of up to five years at a cost of circa $3.5 million for every week it is delayed).”
Transgrid says it has undertaken consultation with affected landowners and community feedback has resulted in changes in route.
“We will continue to work with landowners, the community, regulatory authorities and governments to find solutions to balance local impacts, consumer costs, time constraints and critical supply reliability.,” the spokesperson said.
“Significant changes have been made to the HumeLink route in response to landowner and community feedback. For example, the community proposed an alternate western route through the Bago and Green Hills State Forests and subsequent investigations by Transgrid resulted in this alternate route being the most viable route for HumeLink.
“The amended route will remove 10 private landowners from requiring an easement, improve constructability and access and reduce operational impacts, reduce potential biodiversity impacts and associated offset costs, requiring less native vegetation clearing,
reduce the potential heritage impacts in Bago State Forest, reduce the visual impact of transmission line structures from residences and align with NSW Government principles on placing transmission infrastructure on public land where feasible.
“The VNI West community engagement team is currently in the project region, in south-west NSW, for the latest round of information sessions. Information provided by landowners and community members will be considered as we progress the design and delivery of the project.”
NOTE: Farmers are vowing to lock their gates against a “once-in-a-generation” infrastructure project connecting wind and solar farms to energy customers in New South Wales and Victoria. Energy provider Transgrid has unveiled its preferred route for about 200km of the high-voltage VNI West transmission lines through farmland in southern NSW.
