Evolution of Granny Smith Mine's Power System

OVER 20,000 SOLAR PANELS, 2 MW OF BATTERY STORAGE AND 27 MW OF GAS POWER

Our efficient, innovative and scalable microgrid supplies power for Gold Fields' Granny Smith mine, located in Laverton, Western Australia. The flexible power plant helps reduce fuel consumption by 10-13% for the site - which equates to 2,000 less cars on the road.

Read on to learn more about the long-term partnership between Gold Fields and Aggreko and understand the story behind the evolution of Granny Smith mine's power system from diesel to a future-proof hybrid system.

Granny Smith Power System today

One of the largest renewable energy microgrids in the World

2016: From Diesel to Gas Power Station

The Granny Smith Mine is an underground gold mining operation located 740km northeast of Perth, Western Australia. Operated by Gold Fields, the deposit was discovered in 1979 and in 1989 mining commenced on site with the first gold being poured the year after.

Currently, Wallaby is the operation’s active mine, with mining administration and maintenance located nearby. The annual production of the Wallaby mine is in-excess of 250,000 ounces per year.

Back in 2016, Gold Fields were looking to retire their 17.9MW bank of diesel generators at the Granny Smith gold mine in Laverton. As well as this, a new gas extension was also being built nearby.

Aggreko proposed a 22 MW gas power station, with fuel drawn from the new gas extension, powered by our new high efficiency gas-fired engines. Ultimately, this meant Gold Fields could make significant cost savings while reducing their carbon footprint at the same time.

Our containerised gas generators built into 20-foot containers not only provide fuel savings to our clients but also have a smaller environmental footprint over competitors, who use larger units that are more expensive to transport and take up more real estate.

For the one-of-a-kind power station, we also installed a high pressure gas conditioning infrastructure and heat recovery system which optimise power station efficiency and reduce gas pressure from the gas network.

At the time of the construction, the new power station was expected to reduce the mine’s carbon dioxide emissions by approximately 80,000 tonnes over six years and enable Gold Fields to trade carbon credits with the Australian Government’s Emission Reduction Fund.

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Take a virtual tour through our world-class Granny Smith power station

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2018: Start of The Renewable Energy Microgrid Project at Granny Smith Mine

Exactly 2 years after 2016 project, Aggreko started work with Gold Fields to introduce renewables on site.

The plan was to provide 7.3MW of solar power generation, as well as a 2MW/1MWh battery system, to be integrated with the existing gas supply as a hybrid power station - under one contract and with no capital outlay.

“Our mining clients have faced a challenging marketplace and power generation is a significant proportion of operating costs. Our global capability offers additional flexibility which reduces investment and operational risk,” said George Whyte, Managing Director of Aggreko AusPac. “Aggreko’s focus is on fuel efficiency and reliability in line with the power demand over the life of the mine,” Mr Whyte said.

Stuart Mathews, Executive Vice President Australasia at Gold Fields, said that in addition to the cost efficiency and reliability benefits of the new hybrid power station, the upgrade reflected Gold Fields’ commitment to the increased usage of renewable and low-carbon energy sources throughout the Group. Gold Fields is committed to using renewables for at least 20% of total life-of-mine power requirements in new projects.

For the mine operator, the integration of renewables in the energy mix was a demonstration of their ongoing commitment to both environmental sustainability and innovation at its operations. The proposed new measures would reduce company's carbon footprint by utilising the latest hybrid energy technologies.

The new hybrid power system, combined with expansion of the existing thermal power station will meet the increased daily power needs of 24.2MW, with 8MW allocated to the Wallaby underground mine and the remaining 12 power for the processing plant, associated facilities and the mine accomodation camp.

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Learn more about transition from diesel to renewables from this video

Take a virtual tour through the Granny Smith Mine Site to find out how it has transitioned from an outdated diesel power plant through to a modern gas power station and to one of the World’s largest renewable microgrids.

Learn more about introducing renewables into the energy mix of the mine

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2019: The Installation of Solar Power Station and Battery Storage

In 2019, Aggreko installed one of the world’s largest renewable energy microgrids at the Granny Smith mine site. Powered by more than 7.7MWp of solar and backed up by a 2MW/1MWh battery system. Aggreko engineered, produced, constructed and managed the build of the solar power system.

We installed 23,040 solar panels covering 22.68 hectares, which is the equivalent of 181 Olympic Sized Swimming pools, 22 International Rugby Fields or 11 Melbourne Cricket Grounds.

The 2MW / 1MWh battery storage component offers consistency and reliability of the system and provides spinning reserve, ramp rate control, frequency and voltage regulation, fuel displacement and emissions reduction.

Construction of the renewable energy system commenced in May 2019 and on completion it became one of the world’s largest hybrid off-grid microgrids. Integrated with Aggreko’s existing natural gas power generation this hybrid system is an ideal example of sustainable gold mining without compromising on reliability.

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We are thrilled to reach an agreement with Aggreko for the design, installation and operation of this innovative source of renewable energy which will generate nearly enough power to run the mine’s processing operations.”

Stuart Mathews , Executive Vice President Australasia Gold Fields

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2020: Commissioning of Granny Smith Mine Renewable Energy Microgrid

In 2020, we completed installation of the solar PV and battery storage system. The solar PV reduces the need to run thermal generators at the mine, while the battery plant provides essential services such as PV ramp rate control and transient voltage/frequency support. The assets are being managed by Aggreko’s control software platform which rapidly deploys automated responses to avoid issues and predicts future problems.

The mega solar and battery power facility is fully integrated with Aggreko’s existing 27.3 MW natural gas generation and complements Gold Fields’ suite of on-site energy solutions across other operations.

Aggreko’s AusPac Managing Director, George Whyte, said: “Demand for decentralised energy solutions has skyrocketed over the past few years as companies look past the grid for power solutions to help them meet their unique needs. The hybrid assets we’ve delivered for the Granny Smith mine will help Gold Fields reduce operating costs and carbon emissions with the flexibility and capital expenditure savings that comes with rental solutions.”

In total, the battery storage and solar power assets produce around 18 GWh of energy every year with carbon emissions at the mine expected to be reduced by approximately 9,500 tCO2e.

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2025: Positive results of power hybridisation

Solar / BESS expansion was completed in 2025. Currently, Aggreko supplies 100% of site's power needs, operating the hybrid power system under a 15-year Power Purchase Agreement (PPA).

The current power plant configuration includes:

5MW diesel power & 40MW gas power
19MW solar farm
11MW / 11MWh Battery Energy Storage System (BESS)

The system is managed by Aggreko's in-house advanced energy software, ensuring high availability, optimal performance, and seamless integration across the mine, plant, and accommodation facilities.

The hybrid power system at Granny Smith has delivered measurable environmental and operational gains. By cutting carbon emissions by approximately 23,803 tonnes of CO2 annually and saving 47,895 GJ of fuel each year, Gold Fields has significantly reduced its dependence on fossil fuels while improving energy efficiency.

This fully integrated solution ensures consistent, reliable power across the site without requiring upfront capital investment. It supports operational continuity, lowers energy costs, and aligns with Gold Fields’ broader sustainability strategy. Beyond cost and carbon savings, the project demonstrates how innovative energy models can enable mining operations to meet ambitious decarbonisation targets while maintaining productivity.

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Moving Towards More Sustainable Practices in Mining:

Hybrid Power Solutions

The mining industry accounts for over 6% of global energy consumption, and miners have the great challenge of reducing their emissions in line with the Paris Agreement, as well as their own commitments to net-zero emission targets by 2030 and 2050. Aggreko is supporting the industry, as a major growth area for its business, being at the forefront of energy transition.

Hybrid power solutions play a vital role in moving to more sustainable practices in operation of remote mines. With the existing cost-effective and reliable technologies, they are the first step or the industry in achieving Net Zero by 2050.

Learn more about the new and emerging technologies which will assist the industry in reaching this ambitious target.

Evolution of Granny Smith Mine's Power System

OVER 20,000 SOLAR PANELS, 2 MW OF BATTERY STORAGE AND 27 MW OF GAS POWER

One of the largest renewable energy microgrids in the World

2016: From Diesel to Gas Power Station

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Take a virtual tour through our world-class Granny Smith power station

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2018: Start of The Renewable Energy Microgrid Project at Granny Smith Mine

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Learn more about transition from diesel to renewables from this video

Learn more about introducing renewables into the energy mix of the mine

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2019: The Installation of Solar Power Station and Battery Storage

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2020: Commissioning of Granny Smith Mine Renewable Energy Microgrid

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2025: Positive results of power hybridisation

The current power plant configuration includes:

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Hybrid Power Solutions

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Learn more about microgrids from our case studies.

Replacing outdated generators with new technology

One of the world's largest renewable microgrids

Solar Hybrid power cuts costs and emissions

Cost effective hybrid power that lowered gold production costs

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2016: From Diesel to Gas Power Station

Take a virtual tour through our world-class Granny Smith power station

2018: Start of The Renewable Energy Microgrid Project at Granny Smith Mine

Learn more about introducing renewables into the energy mix of the mine

2019: The Installation of Solar Power Station and Battery Storage

2020: Commissioning of Granny Smith Mine Renewable Energy Microgrid

2025: Positive results of power hybridisation

The current power plant configuration includes:

Hybrid Power Solutions

Learn more about microgrids from our case studies.

Replacing outdated generators with new technology

One of the world's largest renewable microgrids

Solar Hybrid power cuts costs and emissions

Cost effective hybrid power that lowered gold production costs