How Economics and Proven Technology Are Paving the Way for Reduced Carbon Emissions in Mining

July 1, 2024
By unlocking the potential of renewable energy with the help of tools like microgrid controllers, mining operations in Australia and elsewhere can make strides towards achieving net-zero goals and reducing their environmental impacts

One of the most energy-intensive industries in the world, mining is a unique process unlike that of most industrial operations. With most mining sites located in remote areas isolated from electric grids, operations depend heavily on fossil fuels, which are used to both power sites and operate the heavy machinery required to mine.

On top of the emissions generated from mining, on-site diesel generators require fossil fuels to be hauled in over long distances, contributing to increased costs and greenhouse gas emissions. And this is all before any refining processes begin to make the mined products usable.

Mining requires consistent and reliable power, which intermittent wind and solar – typically the easiest renewable resource to deploy for remote off-grid power – provide when combined with energy storage. Energy storage is making it possible for renewable generation to offer consistent power in applications like mining, but there is still hesitation in the industry to rely on fully renewable sources for critical industrial sites.

Onsite hybrid microgrids, which combine renewable resources with traditional fossil fuel generators, can alleviate concerns. Managed by sophisticated software, these remote microgrids can autonomously handle the inherent variability of renewable power generation, smoothing intermittency and switching sources for the most economic and environmental benefit without compromising the consistent and reliable power supply needed for mining operations.

A critical and sometimes underappreciated component of a hybrid power generation solution is a software controller at the helm to manage the generation and load. Much like the software controls of an elevator (which we don’t normally think about), a microgrid controller is the brains behind a microgrid’s effective use of dispatchable resources.

A sophisticated microgrid controller is well suited for remote mining operations due to its ability to autonomously manage and maintain a balance between renewable power generation like solar, wind, and storage, with fossil fuel generators on the same network.

Such a controller can manage the balancing act involved in providing stable 100% renewable power while reverting to traditional generation sources when wind and solar are limited and energy storage is depleted. In addition to reducing carbon outputs, increased use of renewable generation also saves on fossil fuel costs.

Australia Demonstrates Opportunities for Clean Energy in Mining

The challenge of powering remote mines is particularly acute in Australia. The country is the world’s largest lithium producer and within the top five for several other minerals, including gold.

Underscoring the importance of mining for Australia, the sector accounts for nearly 14% of GDP – compared to just under 2% in the United States. Mining’s central role in the economy means the sector must have a steady supply of power, which can be a challenge in a vast country where power grids don’t always line up with where extractive resources are.

Given the remote nature of these projects, many Australian mines operate off-grid using their fossil fuel generators. Of 350 mines in the country, more than 100 have an on-site power supply.

The mining industry has recognized the need to find clean energy solutions for these off-grid operations, with the Mining Towards Net Zero Initiative promising to keep mining’s carbon emissions in line with the goals of the Paris Agreement. The country’s net-zero goals are also leading local governments like Western Australia to pursue initiatives to bring more clean energy to mining.

One mining operator is helping lead the way toward net-zero with a project that is capable of operating on 100% renewable energy. Bellevue Gold, a major gold producer in Western Australia, recently announced plans to implement an 88MW hybrid microgrid that will include 6.8MW of solar generation, 24MW of wind, a 15MW/30MWh energy storage battery, and diesel and gas generators.

The project will also include a microgrid controller provided by PXiSE Energy Solutions, which will make it possible for up to 80% of the project’s power needs to be met by renewable assets, as well as periods of 100% clean energy when solar and wind generation are high. The microgrid will dramatically reduce the site’s reliance on fossil fuels as Bellevue Gold strives toward having the lowest greenhouse gas emissions of any major Australian gold project.

The microgrid, which will power the mining facility, processing operations, and related staff accommodations, serves as a vital demonstration of the potential of renewable energy – while reaping significant cost benefits due to less spending on fossil fuels, along with reduced carbon emissions.

Microgrids: The Ideal Solution for Remote Needs

Upgrading infrastructure and expanding the grid to power remote sites can be expensive, time-consuming, and complex, especially if the site isn’t going to be used long-term. Enter renewable and hybrid microgrids like the one being developed by Bellevue Gold: an ideal solution to bring clean energy to remote sites that can be deployed quickly, operate efficiently, and incorporate existing on-site generation.

To manage the power generated by traditional and renewable sources, the microgrid controller coordinates local energy resources and loads by independently balancing real and reactive power and efficiently dispatches resources for resiliency, power quality, and overall economic benefits.

The controller uses weather forecasting and historical usage trends to determine an optimal schedule for dispatching assets, compensating for sudden load changes to maintain reliable, renewable power without sacrificing power quality and consistency.

The controller enables the mine to operate on 100% renewable energy when sufficient sun, wind, or storage energy resources exist, powering up the generators only when renewable sources are insufficient. Additionally, due to the technology's remote capabilities, limited on-site labor is required to operate the system.

The Road to Net Zero

Renewable energy technologies that can supply energy to remote mining operations while maintaining reliable power quality are critical to decarbonization, and hybrid solutions are an effective option for industries that have traditionally been hesitant to fully embrace intermittent renewables.

While mining remains an energy-intensive industry dependent on fossil fuels, the Bellevue Gold project will demonstrate how hybrid microgrids can make it possible to cut carbon emissions while still supplying a constant supply of power.

By unlocking the potential of renewable energy with the help of tools like microgrid controllers, mining operations in Australia and elsewhere can make strides towards achieving net-zero goals and reducing their environmental impacts.

About the Author

Andy Miller is Head of Commercial Development at PXiSE Energy Solutions. He has been with PXiSE since its inception in 2016 and oversees business development and sales. Andy has played an integral role in growing PXiSE by developing comprehensive business and go-to-market plans, establishing strategic partnerships, leading pricing strategy, and conducting techno-economic product analysis.