Renewables

Giant gold mine switches off gas and diesel for first time after completion of largest off-grid hybrid system

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A recently completed 115MW hybrid power system at a massive gold mine in Western Australia has recently been testing its hydrocarbons off (HOFF) functionality which meets the mine’s total energy load is met by wind and solar energy.

The hybrid power system was completed earlier this year by Pacific Energy at the Tropicana gold mine located 330 kilometres northeast of Kalgoorlie that is jointly owned and operated by AngloGold Ashanti and Regis Resources.

The hybrid system combines four 6MW wind turbines, a 24 MW solar farm, and a 13 MW, 4 MWh battery energy storage system, which are paired with 54 MW of gas generation capacity, and is described as the largest off-grid hybrid power system in the Australian resources sector.

Importantly, the renewable energy component of the hybrid system is large enough to be able to be able to power the entire mine on its own.

In an update on the company’s LinkedIn account, Pacific Energy says it has conducted tests including “five fully autonomous transitions in and out of hydrocarbons off (HOFF) functionality over a 72‑hour period.”

It says that during these transition, the mine – whose load is one of the highest in the state was met solely with wind and solar energy,” backed by the battery system which managed a “6MW load step scenario autonomously and with ease.”

Pacific Energy also said that the mine had been power exclusively by the 24 MW wind farm during the night, which it described as “an exciting milestone for a load of this size.”

“The lessons we’re learning through our HOFF testing at Tropicana enable the continued refinement of our advanced control system technology, allowing us to push the envelope on what’s possible for our existing systems and those in our pipeline,” Pacific Energy said.

Joshua S. Hill is a Melbourne-based journalist who has been writing about climate change, clean technology, and electric vehicles for over 15 years. He has been reporting on electric vehicles and clean technologies for Renew Economy and The Driven since 2012. His preferred mode of transport is his feet.

Joshua S Hill

Joshua S. Hill is a Melbourne-based journalist who has been writing about climate change, clean technology, and electric vehicles for over 15 years. He has been reporting on electric vehicles and clean technologies for Renew Economy and The Driven since 2012. His preferred mode of transport is his feet.

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