The hybrid renewable microgrid at Agnew gold mine. Image: EDL.
Industry leaders from Gold Fields, Aggreko and EDL have revealed how sustainable solutions like large-scale energy storage and short-term modular solar power will enable a clean energy transition.
“The inclusion of renewable energy is going to be consistent and growing over the next 10 years,” Aggreko head of global mining Rod Saffy said.
For this reason, power providers and miners alike are putting their heads together to develop solutions which suit an already complex mining industry.
At Gold Fields’ Granny Smith, Agnew and now Gruyere gold mines, the major miner has called in the expertise of power companies Aggreko, EDL and APA, respectively.
EDL chief executive officer James Harman told Australian Mining why renewable energy can pose such a hurdle for mining companies.
“I think the key challenge for the big mining companies is the absolute need for the reliability of energy off-grid,” Harman said.
“It’s essential infrastructure in the same way the rail is – because it’s their route to market.”
To solve this, EDL implemented its solutions at a power station in Coober Pedy in South Australia, proving to Gold Fields and the industry that renewables could run reliably at scale.
Coober Pedy was originally a diesel power station. Now, with support from ARENA (Australian Renewable Energy Agency), EDL was able to turn it into a solar, wind, battery and diesel hybrid station.
“We’ve sustainably run that with over 70 per cent renewable penetration since around 2016,” Harman said.
“We then took the learnings from Cooper Pedy and applied them at Agnew for Gold Fields where we developed Australia’s largest off-grid renewable hybrid at 56 Mw and over 50 per cent renewables. It’s been a huge success.”
One other obstacle to implementing renewable energy for mining is a security of operation.
Not all mines can guarantee they will be operating in five or ten years, ruling them out of renewable energy contracts which require longer terms to become feasible.
Saffy explained how this deterrent can be turned into a positive for miners.
“The other thing we’re seeing is the introduction of mobile renewables for shorter term contracts where companies don’t have the capital, or the business case doesn’t make sense,” he said.
Saffy described a world where mobile and modular solar farms solve a short term need at mining operations, providing better flexibility while still allowing companies to reduce emissions.
Gold Fields manager of energy, operations support and technology James Koerting said renewables were a terrific solution, but would come to require complementary storage solutions.
“Gold Fields is looking at large scale energy storage. This is something that fits well into the business case when you get into the high end of renewable energy,” Koerting said.
“That’s going to be the next component of the microgrids that we build.
“The battery is there to stabilise the grid but beyond that there’s got the be another form of bulk energy storage.”
Regardless of the how or the why, all three industry leaders agreed the when would be sooner rather than later, as industry sentiment towards renewable energy improves.
“Along with safety, this is becoming a must-have instead of a nice-to-have,” Saffy said.
“When we view investor presentations by mining companies, it’s almost always the first thing they speak about.
“What are they doing about carbon emissions, what are they doing about the communities they operate in, and what are they doing about the responsible governance of their organisation.”