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MINING TRUCKS Both GE Transportation and Siemens are working on hybrid and fully battery powered haul truck electric vehicle compared to the baseline diesel only truck and a diesel truck with a small 200 kWh hybrid system. Two versions of fully electric systems were considered, the first charging from an overhead trolley line while moving, the second utilising stationary charging once per haul cycle. The GVW was held constant and the payload was adjusted based on removal of engine systems and adding battery systems. For an uphill haul while the hybrid solution offers a meaningful 4% increase in production with a 3% reduction in energy cost, while a trolley based solution offers the best increase in productivity and reduction in energy cost. Two trolley lines were analysed. Both delivered around 55% reduction in energy cost, while the longer the trolley line delivered a 22% increase in production versus 5% for the shorter line. The longer the trolley line, the higher the productivity on the uphill haul case. “This trade-off of production increase to cost of trolley line depends on the permanence of the haul roads, installation and maintenance cost of the trolley line versus the value of increased production per truck. Because EV trucks are not limited by diesel engine power, they run faster on the grade, completing the haul 20% faster than baseline. The stationary charging requires about 37% of the baseline haul cycle time to charge for each 28 International Mining | MAY 2019 cycle this results in a 20% reduction in productivity. When we eliminate the charging time for the EV truck, the tons/hr are very close to trolley operation. The charge time is accounted for through additional trucks in the fleet to ensure overall mine output. Similarly, this has not accounted for costs of trolley infrastructure.” For a downhill haul, the hybrid solution uses the energy captured hauling downhill to increase return speed on grade and deliver 7% more production while burning 7% less fuel. The EV solution captures 85% of the energy required from retarding downhill loaded. With the increased propel power and speed, the moving cycle time is reduced offsetting the stationary charge time required, resulting in a 3% increase in production while reducing energy cost 88%. The trolley solution isn’t considered as the trolley speed limit reduces overall production in a downhill application. Hydrogen haulage Moving on to a completely different mindset, during Anglo American’s 2018 sustainability performance presentation, Technical Director, Tony O’Neill, said the company was working on an innovative solution to power haul trucks by hydrogen using solar panels. By oversizing the photovoltaic generation capacity at a site, the company would be able to capture enough hydrogen to potentially power a haul truck. O’Neill said this was all part of the company’s plan to create a “smart energy mix that allows us to become carbon neutral”. “That leads us straight to hydrogen,” he said. The approach the company is working on required a different mindset from O’Neill and his team. “What some in my team have done is say, ‘OK, we’re not worried about a return. As long as the project washes its face, what does that do?’ And, what does it do, particularly, if you oversize your power consumption enough that you can actually generate hydrogen?” The decision-making process changes with such a viewpoint, he said. “All of a sudden, we had enough hydrogen, so we could stick it in our trucks. We looked at the trucks and re- engineered the way they work. Voila, we found we could get 5-10% more out of our trucks,” he said. And, this line of thinking and re-engineering has allowed O’Neill to make a bold statement: “Our aim, is to get, hopefully, in the next 12 months, a truck running around using hydrogen.” Solutions like these could provide energy security, price resilience, reduce greenhouse gas emissions, move Anglo to a “hydrogen economy”, and help it develop the next generation mining vehicles, the company said. Komatsu consolidates AHS excellence in Tucson Bringing together product, technology and service experts from across the company, Komatsu recently announced the launch of its global Center of Excellence (CoE) for Autonomous Haulage Systems (AHS). The Tucson, Arizona-based CoE team will be responsible for AHS strategy, planning, marketing, sales support and training; enabling Komatsu to respond faster to customers’ needs in the rapidly expanding autonomous environment. “This is a major step forward for Komatsu’s unified approach to mining,” said Jim Nishiura, VP Global Mining Business Division, Komatsu. “Our diversified FrontRunner AHS team is united by common goals, workflows and strategies to deliver maximum value to our customers as well as our customer-facing teams and distributors.” Shingo Hori, formerly AHS Group Manager for KLTD, and Anthony Cook, formerly VP AHS and Communications for Modular Mining, have been appointed as co-GMs of the CoE. These organisational changes are focused on Komatsu’s business strategy to continually improve company performance and deliver increased value to customers. Since its commercial release 11 years ago, Komatsu’s AHS has achieved the unprecedented milestone of