Gold giant orders biggest off grid solar farm yet as it combines renewables to slash remote mine diesel costs

Australian off-grid power specialist Pacific Energy says it will deliver its biggest solar farm yet, as part of ambitious plans to power a remote Western Australia gold mine with more than 70 per cent renewable energy.

Pacific Energy said on Friday it has signed an agreement with global resources giant, Gold Fields, to design and construct a 35 megawatt (MW) solar farm for the St Ives gold mine, located around 80km south of Kalgoorlie.

The solar farm is a part of Gold Fields’ $A296 million St Ives Renewables Project, announced in March, which will include 42MW of wind power to take the mine site beyond 70% renewables, and cut its emissions in half.

As well as delivering a new benchmark for Pacific Solar, the St Ives microgrid also marks the first time Gold Fields has managed a renewables project in-house.

“Gold Fields is taking firm steps to significantly reduce its Scope 1 and 2 emissions by 2030, and we’re committed to helping them achieve this,” says Pacific Energy chief, Jamie Cullen.

“Our engineers have factored in scalability to the solar design so that Gold Fields could expand its solar contribution almost immediately if it needed to,” Cullen adds.

“A key lesson we’ve learned over the years is that the design needs to be flexible and account for the rapid changes we’re seeing in the renewable energy transition.”

Perth-based Pacific Energy, which in April completed a new $350 million debt facility, has built 93 power stations totalling over 1.1GW and has more than 900MW under contract over a range of generation sources including solar, wind, battery, diesel, and gas.

Among these projects are four hybrid solar, battery, and gas systems with a combined capacity of 82MW which were completed last month at four goldmines operated by West Australian gold producer Westgold – Tuckabianna, Bluebird, Fortnum, and Big Bell.

In August, the company started work adding 24MW of solar, 24MW of wind and a 13MW battery energy storage system to the existing power system at the Tropicana Gold Mine, around 330km northeast of Kalgoorlie.

Once complete, that added renewables and storage capacity will take the microgrid to a total of 115MW, making it the largest hybrid investment in Pacific Energy’s portfolio, and “the largest islanded hybrid power system in Australia.”

For the mine’s owners, Anglogold Ashanti and Regis Resources, the addition of the extra solar and wind will cut diesel and gas consumption at the mine by 96% and 50% respectively.

In Gold Fields’ case, six out of its ten mines and projects are partly powered by renewable electricity, including the Agnew gold mine in WA, which sources from than half its power from its wind, solar and battery.

The company has installed a 12MW solar plant at the Gruyere mine, and is also planning a 11MW expansion to its existing 8MW solar plant at its Granny Smith mine, also in Western Australia.

“This marks a significant step forward in Gold Fields’ decarbonisation journey and another milestone in the delivery of our biggest renewables project to date in Australia,” Gold Fields’ principal specialist – project director Simon Schmid said on Friday of the St Ives project.

“Gold Fields is committed to local procurement where possible and we are proud to support Australian businesses,” Schmid said. “Like Pacific Energy, Gold Fields is putting its words into action and setting a high bar for energy decarbonisation.”

Pacific Energy says it will start civil works on the solar farm in November and expects it to be fully operational in 2026.