Converting to an all-electric mine brings many advantages, but also involves important considerations for accommodation of changes associated with charging methods, ventilation and cooling, mine cycle and schedules, risks, and maintenance and operations requirements. (Photo: MacLean Engineering)

If recent contract awards are any indication, state of the art in the current ground-support fleet market is characterized by battery electric vehicles (BEVs). Mines are increasingly buying battery-electric bolters, shotcrete sprayers and scalers for both existing operations and new mines, in some cases destined for projects designed specifically for an electric fleet, in others for assimilation into a mixed fleet of diesel
and electric units.

As one example of battery electric machines going into new mines, MacLean Engineering announced its SS5 EV shotcrete sprayer will be included in Glencore Canada’s purchase of BEV equipment for the Onaping Deep project, a mine being developed under the existing Craig mine in Onaping, a historic base metals mining hub in the Greater Sudbury region of Ontario, Canada. Glencore is designing the $1.3 billion Onaping Deep mine as an all-BEV operation, and the MacLean BEV fleet at Onaping will comprise units for explosives charging, secondary reduction, shotcrete spraying, concrete transport and utility vehicles. 

With Epiroc, Normet, Sandvik and others also offering BEV product lines, the direction of fleet makeup in the underground sector toward electrification is clear; what isn’t quite as clear is how to make the journey to zero carbon emissions less painful for mine operators in terms of cost, design and operational impact — identifying, for example, the best way to approach mine design when transitioning from tradition-
al mechanical to an electrified operation; how to integrate heavy production vehicles as well as light and utility underground vehicles into fleet operations; and how to configure current and future mine infrastructure elements for maximum fleet efficiency.

Although support vehicles such as bolters, shotcrete sprayers, scissor lifts and cement haulers account for only a small percentage of fleet emissions — drilling, blasting, haulage and loading units represent more than 80% of operational emissions in most cases —  ground support equipment nevertheless needs to be as emission-free as the rest of the fleet to achieve carbon-neutral production status. It also needs to fit into a mine’s overall production scenario, work methods and infrastructure limitations to ensure best overall results in working toward a targeted electrification goal. And, as mining’s digital footprint expands, ground-support equipment suppliers will be asked to offer enhanced automation features and greater ability to access data that can be used to check and improve a mine’s ground support design and installation methods. E&MJ looks at how industry experts recommend prospective BEV customers prepare for future fleet electrification. Next month, there will be a discussion with a leading mine-utility vehicle manufacturer about the design, performance and potential benefits of battery electric propulsion.

The First Step

The ancient adage “a journey of a thousand miles begins with a single step” was intended for spiritual motivation, but it also applies to integration of BEV ground support equipment or any type of BEV fleet integration for that matter, because it needs to begin with a thoughtful appraisal of basic infrastructure. Recognizing the industry’s need for an organized outline addressing such a broad topic, the Global Mining Guidelines Group recently released an updated version of its Recommended Practices for Battery Electric Vehicles in Underground Mining, which is formatted to lead readers through a structured evaluation of critical considerations for BEV operations, starting with an overview of the advantages and disadvantages of BEVs in underground mining when compared to diesel vehicles; guidance for building a business case and considering the scope for implementation; mine design factors needed to accommodate BEVs; plus charging and vehicle performance. 

E&MJ spoke with Maarten van Koppen, vice president of product management at MacLean Engineering, and one of three project leaders for GMG BEV guideline development. He explained that the updated version is intended to provide guidance and an overall discussion about the benefits, drawbacks, and planning requirements for designing and implementing a BEV fleet within an existing or new mine. It aims to strike an appropriate balance between standardization and innovation by providing key considerations, questions to ask, and guidance on where to look for further information.

Van Koppen said BEVs, once regarded as novel equipment, have entered the mainstream of mine fleet considerations and are now viewed as just another power option along with diesel. However, their growing familiarity doesn’t mean they can be added to a mine’s operational fleet without careful advance planning. Presented in the figure below, for example, are some core isssues the GEG guideline recommends any prospective BEV customer consider before trying to integrate this new technology into their mine.

The guidelines also include salient points to consider for charging infrastructure, ventilation and cooling, battery and fire safety, training and risk assessment (financial, production, health and safety and environmental).

In order to simplify comparisons between different brands and types of BEV for evaluation purposes, the guidelines recommend that OEMs openly communicate BEV machine, battery and charger performance metrics based on accurate field testing with standardized methods and environmental parameters, thus reducing uncertainty and discrepancies in performance expectations. The most significant performance requirements, in the opinion of the GEG guidelines team, are: 

• The ability to achieve the same or better output for a given duty cycle as a comparable diesel unit.

• The energy requirements to perform the duty cycle and number of such cycles capable by the battery energy stored on-board before charging is required.

• The time required to charge or swap the battery.

Next month, this article will take a look at how one manufacturer of both diesel and battery-electric ground-support vehicles is developing its BEV product line to meet the present and future needs of underground operations.