Energising mine closure through renewables

Adapting old mine sites to generate clean energy has long-term benefits for companies, communities and the environment.

Mine-closure planning traditionally focuses on reducing a site’s environmental liability, with the goal of restoring the landscape as close as possible to its pre-mining status. 

But what is less considered is the potential for mine-closure planning to create long-term benefits by constructing renewable energy assets on old sites. 

“Renewable energy is an exciting opportunity to explore in mine-closure planning,” SRK Consulting principal consultant – mine closure Danielle Kyan said. “It’s early days, but there are more conversations underway about the potential for construction of renewable assets on old mine sites.”

Kyan emphasised, however, that renewable assets may not be feasible on all mine sites. 

“The key is to be open-minded and ask questions about renewables early in the mine-closure planning process,” she said. “The projects are emerging.”

A key example is the former Kidston gold mine, about 275km north-west of Townsville in Queensland. Once home to Australia’s largest open-cut gold mine, the project closed in 2001 after 90 years of operation. 

Genex, a power company, is now transforming the site into a clean-energy hub by combining solar, wind and pumped-storage hydropower. This landmark conversion of a disused gold mine will generate enough electricity to power 143,000 homes for eight hours – and is expected to create at least 500 jobs during construction.

The Kidston Pumped Storage Project essentially turns the mine’s massive open-cut pits into a giant battery by pumping water into an upper energy-storage reservoir when energy prices are low. It then releases the water through reversible turbines into the lower reservoir to generate power when energy demand is high.

The facility will store energy from an operational 50-megawatt (MW) solar farm, as well as a planned 150MW wind farm due for completion in 2024. 

 

At the Muswellbrook coal mine in the upper region of the Hunter Valley, New South Wales, planning is underway to transform Australia’s oldest open-cut coal mine into a major renewables precinct. 

In addition to a pumped hydro project, there is potential to add solar, battery storage and green hydrogen facilities to the mix. 

Kyan expects more mine closures in Australia this decade to involve the construction of renewable infrastructure. 

“Some mines suit wind, solar, hydroelectric, geothermal or other renewable assets,” she said. 

“The mines are typically on large, cleared areas of land, have been used for industrial purposes, and have existing infrastructure and a potential workforce.”

Many mining companies already use renewable technologies. 

“We see a number of mines in remote areas installing renewable energy grids to power their sites,” Kyan said. “They’re using renewables in an operational capacity to reduce the project’s carbon footprint. 

“The next step is exploring renewables in mine-closure planning strategy to create new opportunities.”

Kyan says building renewable energy assets on old mine sites potentially has long-term benefits for companies, communities and the environment. 

Companies 

“Mine closure has always been thought of as a cost,” Kyan said. “Renewables can provide an opportunity to develop new income from disused sites. 

“That could change how we think about and fund mine-closure.”

There are also opportunities for mining companies to collaborate with energy companies on developing renewable clean-energy projects. The Muswellbrook Pumped Hydro project, for example, is a joint venture between AGL and Idemitsu Australia Resources. 

Current projects have benefited from government collaboration and grants. The Australian Renewable Energy Agency (ARENA) provided $47 million of funding for the Kidston project. 

“Federal and state governments are showing significant interest in creating renewable energy precincts around old mining sites – and providing some funding for feasibility studies,” Kyan said. 

 

Communities

Renewable projects on old sites create jobs, and in coal and other fossil fuel sectors, job losses are expected in coming decades as the world transitions to clean energy. 

“When a mine closes, some of that site’s skilled workforce could be used in the construction and operation of a renewable asset, providing communities with options post mining,” Kyan said. 

“That’s a much better outcome than a mining town losing a big part of its workforce when the mine closes.”

Greater energy security for communities is another positive. 

“A new renewable energy project on an old mine site could help power homes in the region, as the Kidston project will do in far north Queensland,” Kyan said. 

“This is particularly important in remote areas where the reliability of energy supply is an issue.”

Environment

Renewable projects at old sites have two main environmental benefits: first, providing a revenue stream for mining companies to invest back into mine-closure mitigation measures and ongoing land rehabilitation; second, the asset adds renewables to the energy mix, reducing reliance on fossil fuels. 

“It’s a way for the global mining industry to play a bigger role in climate-change mitigation and adaptation,” Kyan said.

“This issue is ultimately about a social licence to operate. Imagine if we can take a mine that produced coal or another commodity for decades and help it become part of a clean energy precinct. 

“The disused mine wouldn’t just be an environmental liability to manage. Through renewables, we could start to think of it also as an asset.” 

Best practice in renewables and mine-closure planning

1.  Start early: Consider the potential of renewable energy assets within mine-closure strategy. Encourage your board and management to ask questions about renewables within closure planning.

2.  Be realistic: Construction of renewables may not be feasible in many mine closures. Much depends on the mine’s location and proximity to other energy infrastructure, the nature of the mine, and whether it suits various forms of renewables.

3.  View renewables as complementary: The core task of mine-closure planning is to restore the environment as close as possible to its pre-mining status. Renewable assets from mine closures should be viewed as an additional benefit for companies and communities, not a substitute for the main environmental goals of mine closure.

4.  Invest in research: Understand whether your mine site is amenable to solar, wind, hydro or other forms of renewable energy, and assess the feasibility of transmitting that energy to nearby communities through the energy grid. Analysis of any environmental implications of renewable infrastructure on the site is also needed.  

5.  Understand the regulatory/industry landscape: Identify if your mine is in, or near, a region that government has deemed to become a renewable energy hub. Assess the availability of government grants to research building renewable assets. Determine companies in the energy sector that might be open to discussions about taking the project forward. Seek a specialist adviser. 

6.  Consider the ESG implications: Constructing a renewable asset can create jobs for local communities, reskill displaced workers from the mine closure, and enhance energy security in the area. Part of the revenue generated could be allocated to community or environmental issues, leaving a positive legacy after the mine closes and bolstering the company’s environmental, social and governance (ESG) performance.

7. Engage early: Proactive engagement with communities, government, industry and other stakeholders on renewables is vital in mine-closure planning. Does the community want wind and solar infrastructure on the mine site? Do other industries, such as farming, support the plan? What is the local council’s view?

8. Share lessons: The use of renewables in mine-closure planning is at an embryonic stage. It’s important for the mining industry to share knowledge and insights about the development of renewables – and the hurdles these projects face – on old mine sites. 

SRK Consulting is a leading, independent international consultancy that advises clients mainly in the earth and water resource industries. Its mining services range from exploration to mine closure. SRK experts are leaders in fields such as due diligence, technical studies, mine waste and water management, permitting, and mine rehabilitation.

To learn more about SRK Consulting, visit www.srk.com. 

This feature appeared in the October issue of Australian Resources & Investment.

Australian Mining.

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