Aurora Energy will start work next year to future-proof Queenstown’s power supply.
Service delivery general manager Richard Starkey said the company would replace an existing retaining wall by the Queenstown zone substation, to ensure the new buildings could be constructed to an earthquake rating of "importance level 4", meaning they must be operational immediately following an earthquake or other natural disaster.
The substation supplies power to more than 2600 customers in Queenstown and Glenorchy, and connects to substations at the Commonage and Fernhill and the Frankton grid exit point, where Aurora connects to Transpower’s national grid.
Mr Starkey said along with an expectation of a reliable power supply, Aurora wanted to increase capacity in the resort, as more customers continued to electrify their homes and businesses.
"We want to ensure we can enable these future energy choices and a robust network is central to our region’s efforts to decarbonise."
The project, which would continue into 2025, would also lay the groundwork for the future outdoor 33kV switchgear replacement project, where a new indoor switchgear building would be constructed after 2030, he said.
In August, Aurora finished a project to install a new 33kV underground cable, which runs from Frankton to Malaghans Rd, to provide increased capacity to cater for the "significant growth and new development" expected in the area.
That followed a series of power cuts last winter, during which more than 2300 customers, including Coronet Peak, were left without power three times in three weeks, due to unexpected faults and tripping.
Until the new line was installed, Arrowtown, Arthurs Point, Coronet Peak, Dalefield, Gibbston and The Remarkables ski area were supplied by two power lines that shared the load between them, with limited access to an alternative electricity supply in an outage.