Paul Lucey’s advice to attendees at the 2023 Advancing Net Zero Mining conference run by the Minerals Research Institute of Western Australia was, essentially, don’t assume big miners who’ve announced massive decarbonisation spending plans are on track to hit their emission reduction targets. Or get anywhere near them.
The 30-year industry veteran, currently Worley’s principal mine electrification and technology, told the Perth conference technology was a key barrier to ambitious 2030-to-2035 goals. Throw in mining’s protracted capital investment cycles and even longer-range targets could be a stretch.
A “realist’s perspective” was the conference session moderator’s description of Lucey’s talk. But it was also a clarion call to those advancing new solutions to mining’s “carbon-free mobility” challenge to double down because much current planning hinges on legacy equipment and systems that seem unlikely to enable the industry to both economically meet future “critical” material demand and simultaneously shrink its carbon footprint.
Lucey wrote recently: “At the moment mining is spending about a third of what it needs to be spending and some of that money is being spent on unicorns and fairies. I would suggest a number of [decarbonisation] projects will evaporate over the next couple of years and be replaced by more realistic projects. Further to this, if your plan was to wait until someone else solves the problem, you aren’t going to achieve your target.
“The practicalities of building renewable energy farms three-times the size of your mining footprint are starting to hit home.”
He told this week’s conference one of the key reasons he joined Worley over a year ago was to “look at how you electrify mobile equipment, which is probably one of the hardest things to do on a mine site”.
“I often tell companies that if you are looking to reduce your carbon emissions and you have a target, this is the very last thing you should look at because it is by far the hardest thing to actually do,” Lucey said.
“Worley is a large engineering firm. A lot of what it does is around energy. It has a long history in energy projects around the globe, and all kinds of energy. And even with all that background, the decarbonisation of mining is a massive challenge.”
Work by the company last year to probe the scale of the challenge found circa-36,000 of an estimated 54,000 haul trucks at mines today would need to be modified (or replaced) for carbon reduction by 2035 for the industry to meet publicised targets. As it was split between 2030 and 2035 targets, more trucks would need to be converted before 2030 than after 2030, reaching a peak conversation rate of about 5000 trucks per year by 2030. The research found it was “unlikely mining would achieve this rate with its current rate of preparation”.
Lucey said new battery-electric haul trucks were unlikely to hit the market commercially until 2030 and ramp-up would take more than five years.
Without “significant intervention” there would be a considerable gap in the market between required and planned vehicle conversions.
“Now, Australia has around 10,000 haul trucks, give or take 1000 or so, and we need a solution for about 6000 of them,” Lucey said.
“That’s a lot of haul trucks between now and 2035, and for the majority of them companies are looking for a solution between now and 2030.
“Battery haul trucks aren’t really going to hit the market until about 2030 and if you haven’t already bought some, or you’re not in the queue, it’s too late.
“Which means you need to find a different solution going forward.
“There’s probably about 50 solutions you can possibly do, but we narrowed it down to [the top ones] people were looking at.
“The top one, hydrogen … just gets worse as the years go on.
“Every time we model it, it just comes out worse, because the problems that companies thought they were going to solve in putting a fuel cell onto a haul truck are not easily solved … To the point now that I think there’s only one company still pursuing hydrogen haul trucks.
“So I don’t think we’re going to see hydrogen haul trucks in the next five-to-10 years.
“The battery haul trucks on their own are quite expensive.
“You currently have three competing technologies in the battery space: NMC, that’s the one that catches fire; LFP, which kind of sits in the middle; and LTO. And I’ve done work with all three.
“LTO probably has the longest life, but it’s an incredibly heavy and expensive battery. You’ll find it in China and you’ll find it in Europe on busses and trucks that have trolley systems, and they work really, really well for that. But the moment we carry around heavy stuff it’s a very difficult battery to get into a [mining] truck.”
For the (currently) more widely used NMC lithium-ion batteries, Tesla’s $630/kWhr for residential storage units looked more like $1800/kWhr (estimated average) for heavy equipment batteries, while the 6.25kg-per-kWhr in a Tesla vehicle looked more like 10kg/kWhr in a heavy vehicle.
“It’s very, very heavy,” Lucey said. “For a 550kWhr battery you’re probably looking at around 6t by the time you get it into the truck.
“When you consider how heavy these things are and how much power is required on a whole truck, you will find that you run out of weight, and you’ll run out of space. And even then you’ll have to go and charge it up every half an hour.
“And you need renewable energy to then go into that.”
Lucey said about two-dozen types of hybrid systems that included mixed fuel, biofuel and battery-hybrid systems loomed as key interim carbon reduction measures.
But the bigger picture was very much a work in progress.
Worley mining technology and electrification specialist Alicia Bunting told the conference audience there was widespread recognition that the energy transition shift to electric mining fleets needed to happen concurrently with a transition to clean energy.
“However, investing in onsite renewable alone, such as solar and wind, is not the silver bullet,” she said.
“It must be considered as a larger holistic approach.
“The vast land clearing alone for industrialised solar power farms are three-times your mining footprint. To give an example of the magnitude of power generation required for an electric haul fleet, a single ultra-class haul truck for one hour is equivalent to the amount of solar panels needed to power 100 homes. Running a single ultra-class haul truck for a whole day will use as much power as a small town.
“So you can imagine the amount of renewable power and solar panels needed if you have 300 of these running around.
“It stops becoming sustainable and is almost counterintuitive.”