Transpower considers investment options to ensure reliable supply as electricity use increases in the South Island

24 Aug 2023

High-voltage towers in the South Island

Transpower today published a consultation outlining options for investment that will ensure electricity continues to be reliably supplied to the upper South Island as electricity use increases.

Electricity use across the upper South Island has been rising steadily, particularly during summer, when power is used for irrigation. With the growing shift toward a lower carbon, more electrified way of life, demand for electricity is expected to increase further as coal-powered buildings and industries transition to using renewable electricity.

Transpower’s national electricity transmission network requires investment to ensure the increased volumes of power anticipated in the next decade can be transmitted safely and reliably from where the bulk of the region’s electricity is generated in the lower South Island to where it is used.

Transpower’s General Manager Grid Development John Clarke explained the reason for the investment in more detail.

“Over the last 70 years, we have periodically invested in tools and equipment to increase the capacity of the power lines into the region as it has grown,” he said.

“Voltage stability has also been a recurring issue in this part of Aotearoa New Zealand, because power is transported long distances from the Waitaki region to Ōtautahi Christchurch and further north as far as Te Tauihu-o-te-Waka, the top of the South Island.

“Now we are looking at options for another investment to further increase capacity and also ensure we maintain voltage within an acceptable range. Voltage outside of the acceptable range can cause power surges, power cuts, and severe impacts across the power system. The investment we are consulting on will ensure power supply remains of sufficient volume and appropriate quality.”

Transpower’s consultation is an essential part of its infrastructure planning. Local input can provide detailed information it is not aware of, such as potential new generation, planned commercial or residential developments, or significant industrial conversions from fossil fuels to electricity. This helps Transpower better understand what is happening and when, and what the future need for electricity will be.

Mr Clarke continued, “We know that ultimately, we will exhaust the ability to increase the capacity of the existing power lines from the south with investments in equipment and tools. At that point, it’s likely we will need to consider planning a new transmission line unless significant new generation is developed in the upper South Island.

“However, the options we are considering now will defer potential major investment until the mid-2030s. We welcome feedback on the investment options in our consultation which address the more immediate constraints, to help ensure Transpower continues to provide a reliable, safe power supply across the upper South Island.”

“We will use the information we receive through this consultation to refine our thinking and planning,” adds Mr Clarke.

Transpower is seeking feedback about its thinking, assumptions, and the early options it is looking into as it plans for future growth across the upper South Island.

Transpower’s consultation runs until 6 October 2023. Read the consultation information.

 

 

Who we are

  • Transpower’s high-voltage, national electricity transmission network brings power from where it is generated to grid substations across New Zealand.

The consultation information

  • The consultation is open until 6 October 2023. You can find out more about the consultation, how to submit, and all the relevant documents on Transpower’s website  https://www.transpower.co.nz/projects/upper-south-island-resiliency-project
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Map of South Island indicating upper South Island area

“Upper South Island”

  • For clarity, we are using the term “upper South Island” for the northern portion of New Zealand’s South Island extending from Timaru and Tekapo northward.

For more information

Please contact Nathan Green, Transpower Principal Communications Advisor on 027 387 5256.

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