How to easily slash mining emissions

As mining companies look to slash emissions, robust and reliable renewable energy solutions are key.

While a new year has begun, the global energy transition is only just heating up.

According to the Climate Change Authority’s 2024 ‘Sector Pathway Review’, emissions from Australia’s resources sector equalled 99 million tonnes of carbon dioxide equivalent in 2022, representing 23 per cent of the country’s total emissions in that year.

For Australia to achieve net-zero greenhouse gas emissions by 2050, decarbonising the mining sector is key.

This will see solutions such as battery energy storage systems (BESS), wind farms, and solar microgrids implemented across both brownfield and greenfield sites.

Aggreko head of energy solutions Asia-Pacific Greg Lunt said there has been a substantial increase in the number of mines looking for renewables and hybrid power stations in recent years.

“Several mid-tier miners are leading the way,” Lunt told Australian Mining.

“The Tier 1 miners are probably a little bit slower, but they are definitely looking to decarbonise their operations. I think it’s due to the decision-making timeframes, approval processes, and the number of studies larger companies tend to go through.

“Current fuel sources being used at mine sites have a big impact on the economic benefits of renewables. Some Tier 1 miners have assets connected to gas pipelines and depending on their location, their fuel cost can be very low, making the shift to renewables less financially attractive.

“Most new mines these days generally end up implementing a hybrid power station as it provides the lowest cost of energy.”

Hybrid technology refers to one renewable energy system being integrated with another.

Aside from reducing emissions, benefits of a hybrid solution include having the ability to scale to meet different energy demands, being cheaper to run compared to standalone gas or diesel systems and being able to provide uninterrupted power during outages.

Lunt provided insight into the kinds of hybrid plants being installed throughout Australia.

“The hybrid solutions being installed at the moment are pushing the boundaries of technological advances,” he said.

“Power stations are going completely thermal off, meaning they’re just running on renewable energy at portions of the day with no gas or diesel engines running. That requires a bit more engineering than what we’ve seen in the past.

“Wind turbines are also being implemented at various mines, so you’ve got a combination of wind, solar, battery and thermal providing energy with a large portion coming from the renewables.”

If a mine site is yet to move away from fossil fuels and embrace renewable energy, there can be challenges.

These include the cost of investing in low-carbon energy sources and its associated infrastructure.

To help make the jump, mining companies can work with an independent power producer (IPP).

Aggreko, a leading IPP in Australia, has over 60 years’ experience and provides a wide range of innovative and flexible modular energy solutions.

“If companies make use of an IPP such as Aggreko, they can rely on the engineering and analysis capability we have built up and solutions can be developed far quicker than if they were to go and undertake the studies themselves,” Lunt said.

“Accessing energy ‘experts’ that understand these projects can also be challenging for clients.

“An IPP model allows the client to avoid upfront capital and enter into a service agreement for power supply. These agreements include the necessary drivers to ensure that a hybrid power station optimises the use of renewable energy and runs efficiently. The fuel savings alone can often pay for the power station.

“Companies such as Aggreko can swiftly devise the optimal solution that provides the lowest cost of energy. It’s a fast-track approach, as long as they’ve got the land and approvals.”

Aggreko has seen significant success in the mining industry, both in Australia and internationally.

The company has worked with Gold Fields extensively to implement various energy solutions at its Granny Smith gold mine in Western Australia.

Following the installation of a gas power station in 2016, Gold Fields reached out to Aggreko to see how clean and flexible off-grid energy solutions could be integrated into its power package without compromising the micro-grid stability or reliability.

The discussions led to a solar hybrid solution being commissioned in 2020. Aggreko combined almost eight megawatts (MW) of solar power generation and a 2MW/1MWh (megawatt-hour) BESS with the existing gas supply to create a hybrid power station.

The package comprises more than 20,000 solar panels, 2MW of battery storage and 27MW of gas power. The assets produce around 18GWh of energy per annum, with carbon emissions at Granny Smith expected to be reduced by approximately 9500 tonnes of carbon dioxide equivalent per annum.

In August 2024, Aggreko announced it would expand the solar farm and BESS at Granny Smith totalling 19MW solar capacity, demonstrating Gold Fields’ satisfaction with Aggreko’s solutions and customer service.

Lunt described Aggreko’s work at Granny Smith as a “pioneer hybrid power station”.

“Technology has come a long way, particularly the batteries and the understanding of how batteries are used,” Lunt said. “There’s been learnings from this and other projects.

“Aggreko has other hybrid projects under construction, including two 5.25MW solar farms at Rio Tinto’s Gove operation in the Northern Territory, and a 12.4MW solar farm being added to a diesel power station at the company’s Amrun bauxite project in Weipa.”

An 8.8MW/2.1MWh BESS will also be installed at Amrun. Once operational, the solar farm and BESS are expected to reduce Amrun’s diesel electricity consumption by 37 per cent or approximately 5.5 million litres of diesel fuel per annum. This will reduce annual carbon dioxide emissions by approximately 14,000 tonnes.

Aggreko’s key value propositions include its mobile and modular energy solutions, the constant investment in new renewable technologies, and its ability to leverage global expertise.

“We can lean on our global engineering resources and capability,” Lunt said.

“We have developed expertise in analysing and optimising the use of renewable energy over time, contributing to market development and supporting our customers’ evolving needs.”

As the world shifts towards a greener economy, Aggreko is here to help mine sites embrace renewables and reduce emissions.

This feature appeared in the March 2025 issue of Australian Mining.