expected to start in FY28 and FY29 , respectively . This timing is mostly driven by permitting , component lead times and retrofitting . Once diesel-electric trolley assist is fully deployed , we expect to reduce Scope 1 haul truck emissions by around 30 %.”

He added that before it implements trolley assist , it will roll out autonomous haulage at both mines . “ This made the most sense as it means we can optimise routes , battery charging cycles and avoid the costs of refitting ramps .” Of course no mines are yet running AHS on trolley but it is something both Komatsu and Caterpillar are working hard on given the high profile that trolley is taking in the Tier 1 miners ’ route to net zero strategies .

Tapia adds : “ We have thought deeply about the approach here in terms of timing and scale to maximise value and our plans are based on how to maximise NPV – ie we will only install trolley in ramps where it makes sense to do so for value . At the second stage , the trolley will not only power the electric drive , but it will also charge the batteries while the trucks are operating , so reducing the need to stop for static charging .” Battery trolley will phase in after 2030 – of course there will still be some static charging but trolley with its dynamic charging is very much an

electric enabler as it reduces to some extent the level of headache involved in marrying charging cycles with required productivity and uptime .

He concludes : “ Once the autonomous , trolley and battery electric trucks are proven , we ’ re planning a widespread adoption across our assets , which would enable an efficient , low-risk , zero emissions material handling solution by 2040 .” So it looks like for BHP , for the next two decades , it is looking very much as a trolleyassisted future across many of its sites – initially diesel , then battery .

Later in the presentation there was also discussion by Anna Wiley , Vice President Planning & Technical , Minerals Australia on truck fleets both in the Pilbara and with the BMA coal operations . BHP ’ s Australian operations use roughly 1,500 million litres of diesel in over 1,000 pieces of equipment per year , of which over half is used in about 550 trucks .

Wiley continues : “ Electrification is our preferred pathway to eliminate this diesel . One of the reasons for this is energy efficiency … using hydrogen as an example , we see the greatest losses at this phase due to generation , storage and transportation compared to minimal losses in electricity generation and transmission . Once on board , the fuel needs to be transferred to

energy . In both todays ’ diesel-electric technology , and in a hydrogen system , the fuel is used to generate electricity to drive the electric wheel motors which has additional losses compared to direct feed .”

BHP has calculated around an 80 % overall efficiency from an ‘ electrified ’ pathway , compared with less than half of this for hydrogen . She concludes : “ There would be some downside offsets to this comparable efficiency advantage from electrification , such as how we resolve longterm storage and constraints to mining operations due to power infrastructure . However , our view is that an electrified mining fleet is more economic and more achievable than the alternative fuel sources .”

For Australia , trolley was not directly mentioned with the focus being more on the battery electric trucks themselves . Being a partner with both Cat on its Early Learner program and with Komatsu as part of the GHG Alliance , BHP expects to have its first Caterpillar battery truck for trial at BHP in 2024 and will move to trial a Komatsu battery truck soon after . After completion of successful trials , it anticipates the first battery-electric truck sites being in operation from the late 2020s . www . bhp . com