Hillgrove Resources is set to transform its Kanmantoo open pit mine into a pumped hydro facility in the Adelaide Hills region of South Australia.
Mining at Kanmantoo, whose mine life was extended from 2016 to 2019 nearly five years ago, is now winding down.
The copper mine was in operation from 1970 until 1976, but work by Hillgrove since 2004 has proved up an additional indicated and inferred mineral resource of 34.5 million tonnes grading 0.6 per cent copper and 0.1 grams of gold a tonne.
AGL will develop, own and operate the 250-megawatt pumped hydro energy storage project, while Hillgrove will retain the processing and mining rights outside the Giant Pit.
“The trust, support and growth of the community around Kanmantoo has been deeply valued by us and we are pleased to have found a solution that will continue to bring economic benefits, not just to the local community, but to South Australia more broadly,” Hillgrove chief executive Steve McClare said.
According to the South Australian Chamber of Mines and Energy, the Kanmantoo site has contributed $160 million directly to the community over the last 10 years.
The signing of the binding agreements between the companies was the start of a multiple stage process to progress the project, including the lodgement of a development application in 2020, according to AGL general manager of wholesale markets Richard Wrightson.
AGL would buy the land required for the project from Hillgrove shortly after a final investment decision, which is expected to be made after the completion of processing at Kanmantoo.
“This is an exciting project, which is consistent with our plans to continue to invest in our core energy markets business as customer needs and technologies evolve,” Wrightson said.
“If we proceed and the project is approved, it would be an important addition to our technology mix in South Australia, where we have significant wind and thermal generation.
“It would help us to meet the changing needs of the South Australian energy market, in which energy storage assets are likely to be needed to provide dispatchable capacity as renewables generation increases over coming years.”
The project is expected to be complete and operating by 2024.