THE ELECTRIC AND HYDROGEN REVOLUTION: DECARBONISING MINE HAUL TRUCKS

With the largest mine haul trucks weighing in at over several hundred tonnes and consuming over 300L of fuel per hour, these behemoths have a number of environmental, safety and health impacts. Over 28,000 off-road haul trucks are in operation globally emitting around 68 million tonnes of CO2 per year, according to the Rocky Mountains Institute, so displacing diesel is one of the critical challenges for mines in the journey to net zero emissions. Here, we explore how major mining companies are tackling this challenge head on, trialling hydrogen and electricity as alternative sources of fuel to power their fleets and improve sustainability.

The mining industry has relied on diesel for decades to power machinery, and through that time diesel haulers have offered a low-CapEX, flexible and well-understood solution, with a highly developed supply chain. However, despite offering these benefits, there are a number of risks and challenges.

Not only are they heavy CO2 emitters, they also produce a number of other pollutants. This necessitates extensive ventilation systems in underground mines due to the excess heat and exhaust fumes that heavy diesel engines produce. Noise and vibration protection is also required in order to maintain the structural integrity of tunnels and shafts, mechanical wear of parts and vehicles, and for the health and safety of workers.

They are also very energy intensive, making up 30 to 50 per cent of a mine’s total energy use. Furthermore, refuelling requirements for these machines limits a mine’s infrastructure and smooth operation, and is subject to diesel fuel price volatility, which is outside of the operator’s control but is tied to a mine’s return on investment.

Electric and hydrogen-powered fleets — including transportation vehicles, haulage trucks, and mining machinery and gear — can help resolve challenges of using heavy diesel engines in the mining industry. As electric and hydrogenpowered vehicles produce no exhaust fumes, much less excess heat, and much less vibration than diesel engines, they are more environmentally friendly, safer to work with underground, and reduce maintenance costs. Therefore, they can impact not only the amount of CO2 emissions produced by operations, but also a company’s long-term profitability.

One of the biggest hurdles to the uptake of electric or hydrogen-powered machinery in mining, is that there are currently no large-scale economic or technologically viable vehicles available for mine haulage operations. Another challenge for hydrogen in particular is the need to build the infrastructure to source and create the type of hydrogen fuel needed to support a fleet of haul trucks.

However, mining companies and researchers are tackling this problem head on, partnering with technology and engineering firms, to develop and trial new solutions designed to handle the requirements of the mining industry.

Fortescue prioritising decarbonisation initiatives

Fortescue Metals Group is one mining company working to transition diesel to alternate, more environmentally-friendly fuels like hydrogen.

In its Climate Change Report FY21, Fortescue reported that haul trucks at its mine sites consumed about 200 million litres of diesel and accounted for 26 per cent of its Scope 1 operational emissions or 537t of CO2-e. In the same time period, other heavy mining equipment, including drill rigs and excavators, accounted for around 36 per cent of its Scope 1 operational emissions or 746,000t of CO2-e.

With a target to be carbon neutral by 2030, Fortescue’s renewable green energy and industry company Fortescue Future Industries (FFI) is a key enabler of Fortescue’s carbon neutrality target, investing in technologies to power the green mining fleet of the future.

FFI has established its own research and testing facility in Perth, Western Australia, and this facility is the focal point of innovation and collaboration to accelerate the commercialisation of low emissions solutions. It is investigating the main alternatives to diesel, including battery electric and hydrogen fuel cell options, to ensure the opportunities offered by both technologies can be captured.

One of the projects underway is the design and construction of a demonstration green hydrogen powered haul truck, with testing in progress. It is understood to still be a fuel cell electric vehicle ie FCEV utilising both hydrogen fuel cells and batteries. Testing is also occurring for a green hydrogen powered drill rig, including the important element of ensuring refuelling can occur in the mine pit. It has also begun testing of a hydrogenpowered blasthole drill rig.

Another project that reached a milestone in January 2023 was the development of electric mine haul trucks. Fortescue announced a prototype battery system – using the largest battery of its kind in Australia – was ready to be installed in a zero-emission battery electric mining haul truck the company is developing with Liebherr.

The battery system was completed and delivered by WAE Technologies (WAE).

The state-of-the-art 1.4MWh prototype power system sets the pace for ground-breaking innovation in heavy industry and is a bespoke design intended for integration into a 240-tonne mining haul truck.

A team of 50 engineers and technicians are responsible for developing the pioneering power system, which weighs 15 tonnes, measures 3.6m long, 1.6m wide and 2.4m high, and is made up of eight sub-packs, each with 36 modules, all individually cooled and each with its own battery management system.

It is a massive achievement that has been completed in record time and marks several firsts for an electric mining haul truck battery, with energy storage of 1.4MWH – the highest energy storage of its kind – the ability to fast-charge in 30 minutes and capacity to regenerate power as it drives downhill.

Powered solely by renewable energy, it will help prevent enormous amounts of fossil fuel from being used in the mining industry, with the goal to not compromise the vehicle’s load capacity.

The battery arrived at Fortescue’s workshop in Perth, and was going to be assembled and installed, before being transported to the Pilbara for world-leading testing on site this year.

As part of the mine haul truck decarbonisation activities, Fortescue will purchase a fleet of 120 haul trucks from multinational equipment manufacturer Liebherr, with delivery aligned to its fleet replacement and sustaining capital expenditure forecast. The commitment represents approximately 45 per cent of the current haul truck fleet at Fortescue’s operations.

The phased supply of haul trucks is anticipated to commence following a two-year joint development period enabling the development and integration of Fortescue’s proprietary-owned power system into Liebherr’s proprietary-owned base truck. Liebherr will supply mining haul trucks to Fortescue in both battery electric truck and fuel cell electric truck configurations, in accordance with Fortescue’s requirements.

The first of the zero emission-haul units will be fully operational within Fortescue's mine sites by 2025, with the aim to decarbonise its truck-hauling operations by 2030, as well as to have the units available for commercial sale from that time.

Anglo American unveils world’s largest hydrogenpowered mine haul truck

Anglo American, in collaboration with several partners, is retrofitting a mining haul truck with hydrogen power technology as part of a plan to attempt to attain carbon neutrality by 2040.

In 2019, partner First Mode started designing a zero-emission solution to replace a mine haul truck’s diesel engine, and three years later the hydrogen-powered haul truck made its official debut at the Mogalakwena mine in South Africa owned by Anglo American.

It is the world’s largest mobile hydrogen power plant – a hybrid that integrates hydrogen fuel cells with battery power –with the power plant having to generate two megawatts of electricity each second in order to power the large vehicle.

To reach that output goal, multiple smaller fuel modules to create a hybrid power plant weighing 25 metric tons needed to be designed as the scale of fuel cells required doesn’t exist on the market. The power plant weighs as much as five elephants and is capable of carrying a 290-tonne payload.

The 2MW hydrogen-battery hybrid truck is part of Anglo American’s nuGen™ Zero Emission Haulage Solution (ZEHS). nuGen™ provides a fully integrated green hydrogen system, consisting of production, fuelling and haulage system, with green hydrogen to be produced at the mine site.

nuGen™ is part of FutureSmart Mining™, Anglo American’s innovationled approach to sustainable mining, which brings together technology and digitalisation to drive sustainability outcomes, including its commitment to carbon-neutrality across operations by 2040.

Diesel emissions from its haul truck fleet account for c.10-15 per cent of Anglo American’s total Scope 1 emissions, and if this pilot is successful, it could remove up to 80 per cent of diesel emissions at its open pit mines by rolling this technology across its global fleet.

To further its efforts, in December Anglo American signed a binding agreement with First Mode to combine its nuGen™ ZEHS with First Mode with the intention to accelerate its development and commercialisation.

Upon closing the transaction, the companies will enter into a supply agreement, with First Mode to decarbonise Anglo American’s global fleet of ultra-class mine haul trucks, of which approximately 400 are currently in operation. The rollout across Anglo American’s haul truck fleet over the next c.15 years is subject to committed studies across seven mine sites, certain performance and cost criteria, and relevant regulatory, corporate and shareholder approvals. The supply agreement also includes the appropriate provision of critical supporting infrastructure such as refuelling, recharging, and facilitation of hydrogen production.

Anglo American is also playing a role in supporting broader decarbonisation objectives outside its own business. The technologies and capabilities that it has been developing as part of the nuGen™ project with First Mode present opportunities beyond Anglo American’s haul truck fleet, including across other industries that rely on heavy duty forms of transport, such as rail.

In addition to accelerating the development and commercialisation of the ZEHS technology, the new combined business will allow strategic third parties to co-invest alongside Anglo American and First Mode, offering the opportunity to accelerate their own decarbonisation and participate in the potential offered by the clean ZEHS technology.

UNSW researchers tackle the challenge of hydrogendiesel hybrid engines

There is also research underway for a hybrid hydrogen-diesel engine. The University of New South Wales Sydney’s School of Mechanical and Manufacturing Engineering has developed a Hydrogen-Diesel Direct Injection Dual-Fuel System which will allow existing diesel engines to run using 90 per cent hydrogen as fuel. The system has the potential to reduce CO2 emissions by more than 85 per cent in the process.

The research team said that any diesel engine used in trucks and power equipment in the transportation, agriculture and mining industries could ultimately be retrofitted to the new hybrid system in just a couple of months.

The collaborative research found that specifically timed hydrogen direct injection controls the mixture condition inside the cylinder of the engine, resolves the problem of harmful nitrogen oxide emissions that have been a major hurdle for commercialisation of hydrogen engines.

Importantly, the new Hydrogen-Diesel Direct Injection DualFuel System does not require extremely high purity hydrogen which must be used in alternative hydrogen fuel cell systems and is more expensive to produce.

Compared to existing diesel engines, an efficiency improvement of more than 26 per cent has been shown in the diesel-hydrogen hybrid, achieved by independent control of hydrogen direct injection timing, as well as diesel injection timing, enabling full control of combustion modes – premixed or mixing-controlled hydrogen combustion.

The team believes the most immediate potential use for the new technology is in industrial locations where permanent hydrogen fuel supply lines are already in place, including mine sites where there is hydrogen fuel infrastructure in place.

A paper published in the International Journal of Hydrogen Energy by Professor Kook’s (UNSW) team shows that using their patented hydrogen injection system reduces CO2 emissions to just 90g/kWh – 85.9 per cent below the amount produced by the diesel-powered engine.

A whole of industry effort

Along with these projects, other mining and METS companies are working to accelerate decarbonisation of mine haul trucks and other machinery.

Charge On Innovation Challenge

BHP, Rio Tinto and Vale have come together to launch the Charge On Innovation Challenge in 2021, a global competition for technology innovators to develop new concepts for largescale haul truck electrification systems to help significantly cut emissions from surface mine operations and unlock safety, productivity, and operational improvements.

When the challenge was launched, vendors and technology innovators from around the world and across industries were invited to collaborate with the mining industry to present novel electric truck charging solutions.

The Challenge received interest from over 350 companies across 19 industries, with over 80 companies submitting expressions of interest. 21 companies were then invited to present a detailed pitch of their solution. The final eight were chosen from these 21 companies.

In May 2022, from these 21 companies, the final eight technology innovators’ submissions were selected to progress beyond the Charge On Innovation Challenge, including: ABB, Ampcontrol and Tritium (Australia), BluVeinXL, DB Engineering & Consulting with Echion Technologies, Hitachi, Shell Consortium, Siemens Off-board power supply, and 3ME Technology.

Winners are collaborating with interested mining companies, OEMs and investors to accelerate the technology development to support the future roll-out of zero-emissions fleets.

BHP’s first fully-electric Jumbo

BHP has a medium-term target to reduce operational GHG gas emissions by at least 30 per cent by FY2030, from an FY2020 baseline. Approximately 40 per cent of BHP’s operational emissions in its FY2020 baseline year came from dieselpowered vehicles.

In November 2022, BHP unveiled a fully-electric Jumbo at Olympic Dam, which will be tested for efficiency, productivity and comfort over a 12-month trial period as part of its efforts to reduce operational GHG emissions, including by minimising reliance on diesel.

The 28.7t, 14.5m-long battery-electric Epiroc Boomer M2 “Jumbo” will be powered by a 150kW traction motor and 150kW battery system.

Jumbos are used in underground mining development to drill holes, which are then loaded with explosives and open up new areas. Post-blasting Jumbos install large bolts to stabilise mine walls.

BHP currently operates 16 Epiroc Jumbos at Olympic Dam.

The fully-electric Jumbo will also break new ground in its user experience by reducing noise and vibration, and eliminating heat and the emissions of diesel particulate matter.

The trial of the Jumbo also supports BHP’s efforts to minimise the operational impact of diesel particulate matter in underground mining operations by 2025, as part of its participation in the International Council on Mining and Metals’ Innovation for Cleaner, Safer Vehicles initiative.

The fully-electric Jumbo trial builds on electric vehicle initiatives at Nickel West in Western Australia, Olympic Dam in South Australia and BMA’s Broadmeadow mine in Queensland.

BHP is also collaborating with Caterpillar Inc. and Komatsu to develop zero-emissions electrified haul trucks, and battery-electric locomotives with Wabtec Corporation and Progress Rail.