Mehrzad Ashnagaran Business line Mining, Process Industries, Baden Dättwil, Switzerland,
mehrzad.ashnagaran@ch.abb.com
Mining is an energy intensive industry that requires a stable electric supply. But as the quality of ore grades diminishes and demand for raw materials increases, the industry’s demand for energy is expected to increase dramatically. On the other hand, driven by the need to decarbonize their operations, mining companies are moving away from fossil fuels and increasingly investing in electrification, automation, and battery storage technologies to drive their hauling fleets, heavy machinery, and in-mine ventilation systems →01.
As these trends evolve, mining companies are relying on electric mains substations to step up the voltage from the mains power grid to supply the levels of reliable electrical power required for continuous operations. By providing a stable and consistent power supply, such stations minimize the risk of power outages or voltage fluctuations that could disrupt the activities of safety-critical electrical equipment and systems.
Naturally, associated power distribution systems are designed to accommodate future growth and increased power demand. As mining operations expand or new mines are developed, substations can be upgraded to meet evolving electricity requirements. This scalability ensures that mining operations can adapt to changing needs while maximizing production capabilities. This is of paramount importance when it comes to power quality, which plays a key role in the mining business in terms of ensuring equipment performance and lifespan.
Mining operations rely on a wide range of electrical equipment, including crushers, conveyors, pumps, and motors. These machines are sensitive to variations in power quality, such as voltage sags, harmonics, and voltage fluctuations. Poor power quality can lead to reduced equipment performance, increased downtime, and premature equipment failure, resulting in significant financial losses for the mining business.
In addition, mining operations are subject to various regulations and standards related to power quality. Adhering to these requirements is crucial to ensuring compliance and avoiding penalties.
Furthermore, in the context of an environment that is increasingly reliant on renewable sources of energy, as well as ores that are increasingly located in remote locations, power quality is all the more important because more materials need to be extracted, loaded, hauled and processed. In short, the integration of renewable energy has become a must in the ecosystem and needs to be embedded in mine design.
Round-the-clock operations
Most mines operate on a largely uninterrupted schedule, requiring a continuous energy supply for consistent 24/7 load requirements. However, some key renewables, such as wind and solar energy, are variable and would benefit greatly from battery electric storage technologies. These technologies are improving rapidly and are approaching commercial viability. But they currently still suffer from high costs, limited lifespans, and an unproven ability to be scaled.
This limits the capacity of renewables that can be integrated into mining operations. In addition, achieving the successful implementation of renewable energy and energy storage systems depends on the stability and reliability of power systems, as well as a host of evolving technologies, not to mention the energy supply chain infrastructure.
These factors add up to one very clear conclusion: Power quality is of the utmost importance in the integration of renewable energy sources into the electrical grid. Furthermore, power quality measures ensure that the integration of variable energy sources does not compromise the stability and reliability of the grid. Power quality measures are essential for managing voltage and frequency levels within acceptable limits. Renewable energy sources, especially when interconnected at a large scale, can impact grid voltages and frequencies if not properly controlled. Deviations from standard voltage and frequency levels can cause equipment malfunction, damage, or even system-wide blackouts.
Effective power quality management ensures that renewable energy sources are integrated seamlessly, thus maintaining grid stability and avoiding voltage and frequency fluctuations.
Harmonic mitigation
The connection of renewable energy systems, particularly those based on power electronics, can introduce harmonics into the grid. Harmonics are unwanted distortions in the electrical waveform that can adversely affect the performance of other connected devices and equipment. Power quality measures involve the use of harmonic filters, active power conditioners, and appropriate system design to minimize harmonics and maintain a clean electrical waveform. In a nutshell, power quality is vital to the integration of renewable energy sources as it ensures grid stability, voltage and frequency control, power factor correction and harmonic mitigation. By maintaining high power quality standards, renewable energy systems can be seamlessly integrated into the grid in mining plants, thus promoting sustainable and reliable energy generation while minimizing disruptions to the electrical system.
Electrification is the enabler
Decarbonizing mining operations requires profoundly rethinking mines’ connectivity, monitoring, cycle times and safety while collaborating with multiple partners and OEMs to ensure interoperability →02. Cutting this challenge into bite-sized problems, as well as a willingness to work together across the industry to ensure wide compatibility, has been the key to delivering this innovation.
One of the clearest realizations to have come from these steps has been that mines must be decoupled from diesel fuel. But this is more easily said than done. Decoupling requires development of a technology road map that can guide the planning of new or updated mines with a view to incorporating technology options as they mature, become scalable and cost effective. It is a journey based on a series of well-planned steps – practical, short-term actionable projects, designed to gradually transform mining operations.
The decarbonization of mines typically requires an increase in electrical energy usage, primarily due to the replacement of fossil fuel-powered equipment with electric alternatives. It involves transitioning from diesel-powered equipment to electric vehicles, electric-powered haul trucks, loaders, drill rigs, and other mining machinery. Such equipment requires a battery charging infrastructure, including charging stations that are strategically placed throughout a mine site. The development of an extensive charging infrastructure necessitates additional electrical energy to meet the charging needs of electric fleets.
Decarbonization efforts also involve implementing energy efficiency measures to optimize energy usage and minimize waste. These measures may include upgrading lighting systems, improving insulation, and implementing advanced control systems. Although these measures are designed to reduce overall energy consumption, they can sometimes be offset by the increased energy demands of electrified equipment. It is therefore important to take a holistic view and consider the overall impact of decarbonization efforts on electrical energy demand. This will depend on various factors, such as the scale of a mining operation, the extent of electrification, the integration of renewable energy, and the implementation of energy efficiency measures.
Strategies for managing the increased demand for electrical energy may involve a combination of on-site renewable energy generation, energy storage systems, and demand management practices. Ultimately, the transition toward decarbonization in mines often leads to a higher demand for electrical energy, as it becomes the primary power source for electrified equipment. However, this increased demand can be addressed through a combination of renewable energy integration, energy efficiency measures and strategic energy management practices →03, ensuring a more sustainable and environmentally friendly mining industry.
Considering the above-mentioned trends in decarbonization and the growing demand for integration of renewable energy in the mining industry, there is no time to waste. A critical and comprehensive assessment of the mining industry’s technological and economic needs based on comparative simulation studies must be conducted. Such studies must take the unique needs of different mining operations into account. Only in this way can solutions be developed that provide guidance for practical, customized, best-fit project decisions.
