BATTERY AND ELECTRIC MACHINES
In phase one trials with Barrick Gold at its Turquoise Ridge joint venture gold mine , in Nevada , USA , an Artisan Z50 reached production operation of up to 18 h / d , with speeds of over 10 km / h observed on the ramp to the tip
loaders as they have been designed for level applications .
Huff , who confirmed Artisan developed the battery back for this machine , explained the LH514BE loader ’ s niche : “ Really the focus was to replace a cable loader that intends to operate on multiple levels . The addition of the battery was about tramming to a new location , plugging in
when you get there and mucking on that cable power .
“ Traditionally , if you have multiple stopes operating , you will have to have one loader per stope in this setup .”
During testing at the mine in Canada , the battery ’ s performance was pushed even further , with the mine site completing mucking of a whole stope solely on battery power , according to Huff .
“ We did increase the battery performance enough that the customer is actually using it for battery-only mucking ,” he said . “ It was not necessarily the intent , but it can be used for that .”
Sandvik has produced more than 600 electric loaders powered by cable to date , but this is the first equipped with a battery-assisted drivetrain .
Huff is certain battery drivetrains will become a major part of the underground mining ecosystem in the future , but he acknowledges they could be used in combination with other power and energy sources .
“ All the technologies are a necessary part of the electrification landscape ,” Huff said . “ There are going to be solutions that really benefit from trolley or cable connection , versus the flexibility of battery-only equipment .”
Battery and diesel power could also combine as a power option for future underground machines .
As it stands , battery-electric adoption comes with the fewest hurdles to jump over , according to Huff .
“ Mines that use the same section of ramp , for example , for a long period of time may have a better business case for a trolley type of solution . Mines that operate further from the ramp and are shallower have less of a benefit from those elements ,” he said .
The associated infrastructure cost of these type of trolley solutions – adding power supply stations as the mine expands , for example – can be prohibitive , according to Huff .
“ We found in early deployments , where the industry is right now , we can deploy a battery solution for these mines very quickly , with minimal infrastructure and minimal time to set up that infrastructure ,” he said . “ We can also achieve all the haulage profiles needed since we have a dynamic battery-swapping solution .
“ This allows us to do these long haulage route applications where you would normally think trolley is the only solution .”
Such observations have been made during trials with many Artisan machines , several of which have involved the Z50 .
For instance , in phase one trials with Barrick Gold at its Turquoise Ridge joint venture gold mine , in Nevada , USA , a Z50 reached production operation of up to 18 h / d , with speeds of over 10 km / h observed on the ramp to the tip .
The two companies are now well into a threeyear production trial involving up to four trucks to test even more haulage profiles .
An ongoing Z50 trial at a mine in Canada has observed similar production and ramp speed performance to Turquoise Ridge , Huff said .
He concluded : “ In the short term , we see batteries as the preferable choice for risk mitigation and to avoid that high capital cost and lack of flexibility . It is the best way to get electrification started at a mine site , but there may be business cases that work out in specific types of applications where trolley would prove useful . “ It is all part of the electrification roadmap .” This trend towards battery-electric operation is likely to be aided with the launch of Sandvik ’ s Battery as a service offering . This aftermarket option is being developed to provide peace of mind to customers in their transition to batteryelectric vehicle technology , according to the OEM .
“ The battery is a substantial part of the investment in battery-electric vehicles and optimising battery performance will become business critical with these machines ,” it explained .
Sandvik is currently in the pilot phase of this service offering , with trial projects in the US and Canada representing just a fraction of the market interest , but it has plans to officially release the product to market during the latter part of 2021 .
Asked how it may differ from other similar solutions on the market , Sandvik told IM : “ As battery-electric vehicles are in their infancy in mining , we can ’ t say much for the details of other solutions . Our offering , however , will focus on leveraging our expertise and connectivity capabilities to give a strong advantage in getting the optimal performance from the batteries .”
It expects in the future that such a business model will be the industry aftermarket norm with battery-electric vehicles .
An electrification partner
Epiroc is taking a two-pronged approach to accelerating electrification in the mining sector .
Having already amassed more than 130,000 operating hours from new generation batteryelectric machines that include 7 t and 14 t LHDs ; 20 t and 42 t trucks ; and a range of batteryelectric mid-sized drilling equipment including face drilling , production drilling and rock reinforcement rigs , it is now taking its first steps into offering miners a commercial electrification retrofit option .
IM discussed this mid-life rebuild option in the recent Rebuilds and Refurbs article in IM February 2021 , but Lina Jorheden , Operations Manager with Epiroc ’ s Rocvolt function , provided some further details on the initial underground LHD retrofit plans .
“ The first two loader retrofits will be launched on the market during the year ,” she said . “ We are in the final prototype stages with both kits and the retrofitted machines should be up and running by mid-year in different countries .”
Both kits are being developed in different ways , according to Jorheden , with one specialised conversion project orchestrated by an “ agile global team ” and the other kit leveraging off the existing platform for the Scooptram Battery machine already available on the market . The maintenance barriers to entry for these kits are relatively low , according to Jorheden .
“ The idea behind these kits is that we will utilise our global network , with highly skilled mid-life workshops , to be able to carry out the retrofit ,” she said .
All this hints at both the type of customers the company is aiming this solution at , in addition to the market potential Epiroc feels electrification retrofits have .
“ There are a lot of customers that see this as a good complement to the electrification journey
10 International Mining | MARCH 2021