“We’re excited that the new electric-hydraulic shovel will reduce our emissions by around 3600 tonnes of carbon per year, combined with the fact it is powered by 100 percent renewable electricity sourced from the lower South Island. This machine is definitely a good news story for the mining and quarrying industries in New Zealand.”

OceanaGold started their feasibility study in 2019 regarding the introduction of an electric excavator into their fleet. After a lengthy process, they decided to stay with the clearly proven Hitachi brand, working closely with the manufacturer and their long-time supplier, CablePrice throughout the planning and build process. “This machine has so many of the same parts as our other Hitachi machines, using exactly the same hydraulic system, cab, frame, and tracks as our EX3600 excavators. The main difference is that the diesel engine, fuel tank and radiator have been replaced with an electric motor and electric control cabinet – so everything, including the hydraulic system, is powered by electricity,” explains Pieter.

The shovel configuration on the machine is another change, with the 22 cubic metre bucket, which can hold about 38 tonnes per scoop, digging in front of the machine as it moves forwards, rather than underneath it as it moves backwards.

Pieter says the hydraulic shovel has been plugged into Macrae’s existing high voltage power supply from Ranfurly, which reticulates electricity around the site at 11,000 volts. “We have stepped this down to 6600 volts to power the shovel, which is connected to the grid by a 6600V cable – working in essentially the same way as an at-home extension cord. We have put detailed protocols in place for the safety and protection of our electricians and operators.”

Getting used to operating an electric shovel and managing the power cord as they operate around the worksite have been the biggest learning curves for OceanaGold’s operators, who are a lofty seven metres up when in charge of the massive machine. A team of Australian specialists experienced in commissioning large electric machines was sourced through CablePrice to visit the mine site and work with the operators. “Only a couple of our guys had previously operated a shovel and no one had operated electric machines before, but they’ve picked it up really well. Our operators who are keen to try new things are really shining on this machine.”