Aurora Energy developed a long list of options to increase the supply, which was narrowed to a short list, and we now have a preferred option that balances affordability, reliability and practicality.
Preferred option
This option is for Transpower to build a new GXP near Tarras and for us to use existing subtransmission lines and also build new lines to feed this electricity from the national grid into our local network of power poles, lines and underground cables, to your homes and businesses.
Staged approach
We’re planning the project in stages so we can adjust our plans with the pace of growth and allow for more uptake in rooftop solar, batteries and other smart technologies (also known as distributed energy resources, or DER). This may help push back the timeframes for some of the later stages of this project and we’ll monitor this closely as the project progresses. At the moment, the current uptake of DER isn’t enough for us to delay getting the first stages of this project underway. You can learn more about DER here.
Staging this investment also means we can smooth out the pricing impact to customers. We aim to balance the increase in electricity capacity to keep up with the demand while not building all the new infrastructure at once, because as more customers join our network due to growth, there will be more people to spread the costs across.
Frequently asked questions
There are two existing main (sub-transmission) lines running on either side of Lake Dunstan, from the Cromwell GXP (where we take electricity from Transpower’s national grid) to our Riverbank substation in Wānaka, which then feeds into other areas in the Upper Clutha.
The new GXP at Tarras will increase the amount of electricity that can be delivered into both the Cromwell and Upper Clutha areas. It also improves resiliency and reliability in the overall network thanks to having multiple subtransmission lines.
Other benefits are:
· Existing assets are repurposed, and current subtransmission lines are optimised with a new centrally located GXP
· Supports transmission supply into our Queenstown Lakes network by connecting from Tarras. This frees capacity of Transpower’s existing GXP in Cromwell, which also feeds power into Queenstown
· Facilitates new future large connections such as solar farms and large-scale battery storage to be integrated into the network
We’re still designing the proposed route and will speak directly with any property owners that will be affected to make sure they’re involved at every step.
The new GXP at Tarras will cost an estimated $58 million and will be passed through to everyone connected to our Central Otago/Wānaka network via their power bills (the costs will be spread over time). The new subtransmission (main) lines that will feed from the Tarras GXP into our local distribution network will cost around $65 million. These costs will be funded by allowances set by the Commerce Commission.
It's projected the new infrastructure will cost customers an indicative average of $15 per month if the new mine at Bendigo goes ahead, and an indicative average of $20 a month if it doesn’t (see ‘How does the proposed new gold mine at Bendigo fit in?’).
Electricity infrastructure is expensive and we do our best to balance keeping electricity affordable with continuing to invest in the network to support growth and new technologies that help customers manage their energy use.
If it goes ahead, Santana Minerals will pay for 100% of their new connection costs to supply the mine, including a dedicated substation at Bendigo. This will benefit customers as the upgrade is Stage one of our longer-term project to increase the supply into the Upper Clutha area.
If the new mine doesn’t go ahead, we still need to increase the electricity supply into the Upper Clutha/Wānaka areas and our planning allows for that.
Any questions?
Thank you for your patience as we carry out this work. For more information, please contact us.