Miners should be open-minded about the potential of hydrogen-powered vehicles, despite the mining industry’s current focus on battery technology.
Tyrone Woodfin, a senior mining engineer at SRK Consulting, describes hydrogen fuel-cell mining trucks as a potential ‘end-game solution’.
“Hydrogen is not there yet, but if you’re planning a mine for the next 10–20 years, you should consider the likelihood of hydrogen becoming a viable fuel source during that period,” he told Australian Mining.
The choice between battery or hydrogen fuel cell powered vehicles has varying implications for mining operations.
“Companies are starting to assess the options available to decarbonise the haulage of their mining operations,” Woodfin said.
“Batteries seem to be the primary focus at the moment, and this is echoed by major technology developments from original equipment manufacturers (OEMs). This might not be the case in a decade or more as hydrogen technology develops and the hydrogen industry achieves greater scale and accessibility.
“As it currently stands, hydrogen trucks only exist in prototype form. The mining industry is still testing what works and what doesn’t work for an eventual move away from diesel-powered fleets.”
For now, Australia’s largest mining companies have focused on batteries over hydrogen to decarbonise their haulage fleets. Battery technology is advancing quickly as a result.
Woodfin, a mine planning and scheduling specialist, said most of the world’s mines cannot access hydrogen from external sources.
“Although hydrogen is utilised in industry around the world, green hydrogen, the preferred choice for a decarbonised fuel cell haul truck is currently not commonly available,” he said. “This means a hydrogen-based solution would require investment in the infrastructure to produce green hydrogen, which is an expensive exercise.”
Although hydrogen has its complications, Woodfin said, it remains the closest substitute for diesel power in mining fleets.
“Liquid hydrogen fuel has great long-term potential because it overcomes limitations with battery technology in terms of range and delivers greater flexibility in a mining operation,” he said.
“Take, a deep copper pit for example, with current battery chemistries the energy density is not sufficient for the truck to carry enough energy on-board to exit the pit under its own power.
“The trucks would be reliant upon a trolley-assist to supplement power supply to be able to exit the pit, whereas a fuel cell truck could have the range.”
Trolley-assist systems direct grid-based electrical power to haul trucks in open pit mines through overhead ‘trolley lines’, much like city trams.
More common in overseas mines, trolley-assist systems sometimes require pits to be widened and shut down at times for scheduled maintenance.
In that scenario, Woodfin said, reliability of the trolley system is key to an operation.
“Currently, trolley systems are used to speed up diesel electric trucks on a ramp, the energy to drive the traction motors is taken from the trolley line, and if the trolley is not operational the truck will just continue to rely on its diesel engine,” he said.
Trolley-assist systems are being developed by the likes of BluVein in collaboration with Epiroc.
Ahead of the recent Electric Mine Conference in Perth, Epiroc completed the first-ever diesel-to-battery conversion of its Minetruck MT42 to be the basis of BluVein’s dynamic charging solution and slotted electric rail system.
As it currently stands, mining companies in Australia are increasingly choosing batteries for their future fleets over hydrogen power.
“Battery technology is far more of a known quantity,” Woodfin said. “It’s easier, cheaper and faster to achieve carbon reduction through fleet electrification.
“Major OEMs are developing the technology and there’s a clear runway for them to deliver a product, so the technology is closer to commercialisation. Most of the West Australian iron ore deposits are relatively shallow which makes battery a good solution.”
All major OEM truck providers have committed to or indicated a battery truck is in development.
As for hydrogen, Komatsu recently signed a deal with GE to collaborate on developing a hydrogen fuel cell haul truck and Anglo American’s First Mode is moving to its second iteration to progress from a gaseous hydrogen fuel machine tested on an Anglo Platinum site in South Africa to a liquid hydrogen variant to extend its range.
Battery technology for mining is developing quickly. It’s likely that haul truck batteries will have longer ranges, trolley technology will be improved to increase reliability, as will the ability to access sufficient power to drive traction motors and charge batteries simultaneously.
In addition, battery-electric trolley trucks for underground mining are being tested in Europe, quickening the move towards the all-electric mine of the future and carbon reduction.
Woodfin, who joined SRK Consulting this year, hopes hydrogen fuel cells will emerge as a viable option in mining in coming decades.
In a previous role, he helped study alternative-fuel haulage options for operations around the world and can see hydrogen’s viable application.
Woodfin has watched the aviation and automotive industry’s continued development into hydrogen-based solutions and hopes this will spill forward into the mining sector.
“I suspect much will depend on a mine’s location, the depth of the pits and access to renewable energy and hydrogen,” Woodfin said.
“If companies can work together to develop shared hydrogen-generation facilities or access external sources, hydrogen will become more competitive with battery technology over time.
“The key for miners is to understand the advantages and limitations of both technologies, especially from an operational perspective.”
Six considerations with battery and hydrogen power
Recognise the scale of the decision: The decision to electrify mine fleets through battery technology, or use hydrogen fuel cells, has costly implications for mine planning and design. Batteries need charging infrastructure and hydrogen requires on-site generation or access to external hydrogen sources.
Stay aware of technology advances: Battery and hydrogen technologies continue to develop rapidly. Ensure your organisation has access to the latest news on advances in renewable energy technologies for mining, and access to internal or external advice, in what is a highly specialised field.
Look forward: Resist making mine planning decisions around battery or hydrogen infrastructure based on what is available today. Consider where these technologies are heading and how that affects mine planning over long periods. Will the technology be superseded? How can infrastructure implemented with mines for these technologies be ‘future-proofed’ to incorporate technology upgrades?
Aim to collaborate: On-site hydrogen generation, in particular, will require greater collaboration by mining companies, given the cost. With batteries, developing water, wind or hydropower renewable energy sources to power recharging requires community engagement. Could these renewable energy sources benefit local communities during production or after mine closure?
Share learnings: As both technologies develop, it’s important that mining companies share their experiences through industry literature so that other organisations can learn from them. Reducing industry uncertainty with these technologies is the key to a faster move away from diesel-powered fleets and ongoing decarbonisation of mining operations.
Remain open-minded: Mining companies are right to be wary of hydrogen and favour battery technology today. Hydrogen, however, has significant long-term potential as a fuel source for mining fleets and could overcome some of the limitations with battery technologies.
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 June edition of Australian Mining.