The use of diesel fuel in power-reliant Canadian mining activities can be gradually supplanted, at least partially, by harnessing renewable energy sources. Comminution is a significantly energy-consuming mining process that involves mechanically reducing minerals and/or rock to predetermined sizes
[32][48]. As per
[33][49], comminution constitutes approximately 15% of the energy consumption for iron mining and around 21% for gold extraction. Interestingly, transitioning to renewable energy sources is relatively straightforward for these processes because comminution is predominantly electric.
Renewable energy (RE) sources, encompassing solar, wind, and geothermal energy, are increasingly emerging as viable solutions for off-grid and remote mining operations. The successful integration of clean energy to power the Diavik and Raglan mines in Canada’s Arctic region exemplifies the potential of this approach. Another instance is the repurposed SunMine mine in British Columbia, which capitalizes on solar energy. Furthermore, geothermal energy as a sustainable power source has demonstrated its efficacy, as evidenced by the Éléonore mine project in Quebec, which can cover up to 35% of mining energy requirements.
3.2. Replacing Diesel with RE for Transportation
4.2. Replacing Diesel with RE for Transportation
To illustrate, a notable fraction of approximately 10% of the energy requisites for both iron ore and gold mining is allocated to transportation and hauling operations
[34][52]. Since diesel fuel remains a prominent energy source for these functions, particularly in truck hauling, integrating renewables into material handling presents notable challenges. In Canada, employing biodiesel within mining encounters certain hurdles. High biodiesel blends, particularly those derived from non-soy substrates, may undergo gelation in cold weather conditions
[35][53]. However, strategies that are employed to counteract cold-sensitive compounds can also be applied to circumvent gelling issues. Several biodiesel exporters currently employ this approach to warm personalized train carriages.
3.3. Making Hydrogen with RE
4.3. Making Hydrogen with RE
Hydrogen plays a multifaceted role within the mining sector, serving various purposes such as high-temperature heat generation, electricity production, feedstock, fuel for vehicles and mining equipment, and energy storage. Currently, the dominant sources of hydrogen production are oil, coal, and natural gas
[36][55]. Surplus energy can be efficiently transformed into hydrogen and stored for later utilization. Notably, excessive electricity can undergo conversion into hydrogen and be stockpiled for deployment in other mining operations that possess the capacity to integrate intermittent-output renewable energy technologies, such as solar and wind.
3.4. Electrifying Communities Nearby
4.4. Electrifying Communities Nearby
Mining enterprises have historically erected essential infrastructure to cater to the needs of remote mining communities, including electricity supply for housing employees. By leveraging this existing infrastructure, mining companies possess the potential to significantly enhance electrification efforts by extending these services to nearby villages
[37][57].
Capitalizing on economies of scale, mining entities can leverage their substantial power consumption and financial capabilities to establish larger-scale power plants than required for mining operations. This approach enables the extension of electricity access to adjacent communities at an economically viable rate. This endeavor could manifest as a novel micro-grid initiative, where electricity generation from renewable sources is designed to serve both the mine site and the neighboring populace.
45. Electrification Alternatives in Canadian Mines
The shift towards electrification within the Canadian mining sector is already underway. Both ongoing and upcoming mining ventures in Canada are actively transitioning to renewable energy sources and incorporating battery energy storage to meet their electricity demands. Numerous forward-thinking Canadian enterprises are channeling investments into fully electric or hybrid electric vehicles to substitute diesel vehicles, curtail costs, diminish pollution, and embrace clean technologies for a more prosperous and ecological future
[38][39][40][41][42][43][44][59,60,61,62,63,64,65]. However, this transition also ushers in infrastructure, maintenance, and operational challenges mine operators must contend with. Currently, a predominant focus within Canadian mining operations centers around electrifying their haulage systems. This initiative is highlighted by converting several heavy-duty truck prototypes into electrically powered alternatives actively integrated into service.
4.1. Installation of a Trolley-Assist System for Diesel-Electric Trucks
5.1. Installation of a Trolley-Assist System for Diesel-Electric Trucks
Trolley-assist technology has been in existence for a considerable duration. During the energy crisis of the 1970s, sparked by events such as the Yom-Kippur War in 1973 and the Iranian Revolution in 1979, which disrupted oil supplies and led to scarcity and price surges for Western nations reliant on Middle Eastern energy exports, various mining companies explored trolley assist as a means to reduce their dependency on diesel fuel
[45][66]. Although trolley assist offers advantages such as emission reduction, enhanced cycle times, and increased productivity, it failed to gain widespread traction. Multiple factors have contributed to the limited adoption of trolley assist, as outlined in
[45][66]. Historically, diesel prices remained lower than today, and until recently, the mining industry lacked substantial incentives to mitigate its environmental impact.
However, the landscape has shifted with Canada’s recent adoption of stringent climate change regulations and the implementation of carbon taxes. This has prompted the emergence of trolley-assist system installations in mines across the globe, including notable instances such as the Boliden Aitik mine in Sweden
[46][67].
With the recent implementation of the trolley-assist system at the Copper Mountain mine, there are optimistic expectations regarding fuel savings and emissions reductions. The company anticipates that each truck will be able to displace approximately 400 L of diesel per hour or around a tonne of CO
2 emissions. Despite the substantial CAD 40 million investment required for the integration of this innovative system into their operations, the company has identified compelling justifications for this endeavor:
-
Increasing Carbon Taxes: Adopting trolley assist can substantially mitigate Copper Mountain’s carbon tax liabilities as these taxes continue to rise.
-
Escalating Diesel Costs: Using the trolley-assist system, each hybrid Komatsu haul truck consumes 400 L of diesel (equivalent to 1 ton of CO2) per hour. Additionally, transitioning to clean power sourced from BC Hydro offers a more predictable cost structure than diesel’s unpredictable availability and pricing fluctuations.
-
Enhanced Efficiency: Deploying hybrid trucks equipped with trolley assist translates to more efficient mineral transportation within shorter time frames.
-
Reduced Environmental Impact: With the support of the BC Government, Copper Mountain is aligning with efforts to bestow “responsible metals” credentials on their products as they traverse the supply chain. This designation positions these items for premium trading, ultimately augmenting their value.
4.2. Integration of In-Pit Crushing and Conveying Systems
5.2. Integration of In-Pit Crushing and Conveying Systems
In-Pit Crushing and Conveying (IPCC) systems consist of various components, including crushers, entirely mobile in-pit conveying systems, stationary conveyors, conveyor junctions, waste-spreading tripper cars, waste-spreading slewing spreaders, and mineralized material radial stackers
[47][70]. Alternatives to the IPCC framework exhibit diverse configurations. There are three primary types of IPCC systems, each characterized by its distinct attributes.
Compared to truck shovel (TS) options, IPCC systems offer a range of advantages supported by research reviews and real-world production experiences at mine sites
[48][49][50][75,76,77]. The benefits of IPCC systems include:
-
Energy Savings: Conveying minerals through conveyors inherently demands less energy per unit weight than transporting them via trucks
[51][78]. Notably, only 39% of the energy utilized in a truck cycle is dedicated to moving the payload, with the remaining 61% allocated to moving the vehicle’s weight. Additionally, by relying on electricity-based methods, IPCC systems can reduce a mine’s reliance on diesel fuel.
-
Environmental Impact (Dust and Noise): Implementing IPCC systems can reduce noise pollution as conveyors generate less noise than conventional diesel-powered trucks. Moreover, reducing the number of trucks on the road can significantly diminish the dust emissions sources, positively impacting the environment
[51][78].
-
CO
2 Emissions: IPCC systems can substantially reduce CO
2 emissions by facilitating fuel switching. A noteworthy example is found in a Brazilian iron ore mine that has integrated two fully mobile IPCC systems, collectively capable of handling 7800 t/h, resulting in an estimated reduction of 60 million liters of diesel consumption annually
[52][79]. This approach aligns with utilizing renewable energy sources, such as hydroelectric, solar, and wind-based electricity, to transform IPCC into a decarbonized transport mining system.
-
Operational Costs: As mining activities escalate, waste dumps grow, and the pit becomes deeper. This progression leads to longer truck haul cycles and increased demand for additional trucks to meet production requirements. Truck hauling is frequently perceived as more costly than IPCC methods, particularly with increased distances and elevation
[53][80]. Embracing an IPCC system over a truck haulage system can significantly reduce material transport operating expenses (OPEX), owing to potential savings from energy conservation, workforce reduction, enhanced weight efficiency, and lower maintenance costs.
-
Production Efficiency: The continuous transportation approach offered by IPCC systems often translates to increased production rates. This approach involves transporting ore or waste materials to designated locations consistently and efficiently
[54][81].
56. Challenges for RE and Transport Electrification in Canadian Mines
5.1. Technical Challenges
6.1. Technical Challenges
The foremost technical challenges associated with solar and wind energy pertain to their inherent unpredictability and variability. These renewable energy sources can only be harnessed during sunny or windy conditions, with power generation contingent upon factors such as cloud cover and wind speed. This poses a significant incongruity with the continuous and stable power supply demanded by mining operations
[55][82]. In addition, icing is another challenge for wind turbines and solar panels, due to very cold and long winter temperatures (up to −40 °C). This may significantly reduce energy production and affect maintenance due to restricted access. The evolving landscape of battery storage costs can potentially revolutionize the intermittency and variability quandary. However, in the immediate term, battery storage is not poised to entirely supplant diesel utilization in off-grid scenarios
[56][83].
5.2. Expertise and Logistics
6.2. Expertise and Logistics
While mining enterprises exhibit an unwavering commitment to elevating health and safety standards—entrenched within the industry’s ethos—this diligence does not uniformly translate to power management systems and energy conservation initiatives. Mining conglomerates face a shortage of essential technical proficiency in renewable energy (RE) and hybrid systems. The expertise in designing, operating, repairing, and maintaining diesel-powered systems prevalent in off-grid mining operations lies predominantly within the purview of mining professionals and established suppliers. Regrettably, this scenario constrains the seamless integration of renewable power
[57][91]. Although power providers catering to the sector are gradually introducing hybrid options, only a few mines in Canada, such as Raglan and Diavik, have embarked on the journey of amassing experiential knowledge in RE implementation.
In logistics, Canadian mining corporations have mastered the formidable challenge of supplying heavy fuel oil or diesel to remote mine sites, a feat particularly pronounced in border regions such as the Arctic. Notably, the Diavik mine exemplifies this feat, where ice roads remain the exclusive conduit for truckers and heavy machinery during certain winter weeks. Integrating renewables in such locales can alleviate logistical complexities and expenses associated with fuel transportation
[58][92].
5.3. Financing
6.3. Financing
The initial capital outlay for establishing a renewable energy plant surpasses the cost of incorporating generators into a diesel-based facility, and this cost differential is projected to persist in the foreseeable future
[59][60][61][98,99,100]. This financial aspect assumes considerable significance from a cash flow perspective, especially when contemplating a self-generation setup. The higher upfront costs associated with renewable solutions could extend the timeline for recovering the initial invested capital. Such a capital investment shortfall could be particularly detrimental, considering the benefits of augmenting renewable energy penetration or disseminating electricity to proximate communities
[62][101].
While there are economies of scale to be gained by constructing large-scale solar and wind installations, these advantages are still intertwined with augmented initial capital outflows, subsequently deferring capital recouping. This is further compounded if the mining enterprise shoulders the distribution expenses tied to local electrification efforts, leading to escalated capital expenditures
[63][102].
To circumvent hefty capital expenses, one viable avenue is outsourcing the renewable project to an Internal Power Producer (IPP). However, financial constraints become a significant hurdle when transferring renewable energy (RE) project ownership to an IPP
[64][103]. Many RE IPPs lack the equity to underwrite the project’s initial capital requirements. This predicament could result in banks rejecting loan requests for the RE project due to insufficient capital or imposing elevated interest rates to mitigate investment risks.
5.4. Research and Development
6.4. Research and Development
The Canadian mining sector needs cost-effective solutions to embrace affordable, long-duration energy storage systems for scaling up renewable energy adoption, as well as for incorporating clean heat sources at high temperatures. Additionally, green hydrogen production emerges as a promising avenue for low-emission heating or feedstock purposes, offering the potential for research and innovation
[65][66][67][106,107,108]. Similar prospects lie in developing lighter batteries with enhanced autonomy for industrial applications
[68][109]. Furthermore, the integration of Blockchain technology, which remains largely underutilized in Canadian mines, could enhance transparency, simplicity, and security in investments. Blockchain could also enable the tracing of “green” minerals, thereby contributing to mining sector operations
[69][70][110,111].
5.5. Business Models
6.5. Business Models
The limited availability of flexible renewable energy solutions and the financial constraints many mining corporations face, especially smaller to medium-sized enterprises, contribute to a sense of caution. Policy support will be pivotal in shaping agreements, such as power purchase agreements, aligning incentives and legal frameworks, and fostering net metering for grid-connected mining operations. Analyzing the advantages and disadvantages of RE incorporation can aid governments and stakeholders, including the financial sector, in making informed decisions to support these endeavors.