Energy-Saving Solutions Applied in Belt Conveyors: A Literature Review

Abstract

Belt conveyors are essential systems for the continuous transport of various materials across many industries, particularly in bulk material handling for mining. While they are often the most economical solution, they still consume a significant amount of energy. This article discusses the latest advancements and the current state of energy-saving solutions for belt conveyors. Key solutions include low-friction belts, variable-frequency drives (VFDs), monitoring systems, automation, and regenerative belt conveyors. It is important to note that selecting the right construction parameters, performing preventive maintenance, and using appropriate materials are crucial for reducing energy consumption. By combining these energy-saving technologies with well-chosen construction parameters, it is possible to develop sustainable belt conveyors.

1. Introduction

Belt conveyors are a fundamental means of continuous material transport across various industries, particularly in mining. While they are often the most economical solution, they can also lead to significant energy consumption due to factors such as friction, belt misalignment, and inefficient drive station operations.

Older belt conveyor systems typically exhibit high motion resistance, utilize constant-speed motors, and operate until they fail. This approach results in accelerated wear of components, increased energy usage, and a larger carbon footprint.

Currently, many analyses and studies are being conducted by scientific institutions to optimize conveyor operation [1,2,3]. In response, leading manufacturers of belt conveyor components are developing new technologies that can significantly reduce energy consumption [4,5,6,7]. By adopting innovative construction parameters, implementing intelligent control systems, and enhancing component designs, it is possible to create safer and more sustainable belt conveyors [8].

2. Materials and Methods

2.1. Low-Friction and Energy-Efficient Belts

Energy consumption in belt conveyors is primarily caused by motion resistance, which is a crucial aspect of their operation. This resistance arises from friction, occurring wherever the belt rolls over the idler set or makes contact with the drive pulleys [9,10,11]. Additionally, friction takes place in the bearings of each idler and along the drive shafts. High levels of friction not only lead to increased energy consumption but also accelerate the wear of conveyor components. In recent years, there has been significant progress in energy-saving technologies for conveyor belts.

2.1.1. Modern Amp Miser Belts from Forbo Movement Systems

The modern Amp Miser belts from Forbo (Forbo Siegling GmbH, Lilienthalstrasse, Hannover) Movement Systems are made from a patented low-friction material that reduces resistance. These energy-saving belts generate less tension on the idler supports, greatly decreasing the resistance of the belt as it rolls over the rollers. Moreover, at the pulleys, concentrated resistance is minimized.

Although the specific compositions of the materials used to manufacture these conveyor belts are proprietary and undisclosed, manufacturers assert that the addition of the patented Texglide further reduces energy consumption across various aspects. Amp Miser conveyor belts improve efficiency in bearings, gears, and motors, achieving inverter efficiency rates of up to 96%. This innovation allows for the construction of longer conveyors operated by a single motor, which not only reduces investment costs but also enhances overall system efficiency.

Tests conducted on conveyors in warehouses and airports have demonstrated that Amp Miser belts can achieve energy savings of up to 50% compared to traditional belts. These belts have received a special TÜV certificate, confirming their ability to significantly decrease energy consumption [12].

2.1.2. TransEvo Belts by Semperit

TransEvo belts by Semperit (Semperit Group, Vienna, Austria) represent a new generation of belts designed for use in conveyors in both underground and open-pit mining. Made from special rubber compounds, TransEvo belts significantly reduce rolling resistance on pulleys and can lower energy consumption by up to 25%. This enables the use of smaller drive pulleys, which, in turn, allows for the implementation of smaller gearboxes and less powerful drives.

These belts also feature a reduced unit weight, enabling them to be mounted on drums with smaller diameters, thereby decreasing the load on drive systems and, consequently, on the engine. Depending on the conveyor type and design, the maximum forces exerted on the belt can be minimized, leading to lower required nominal strengths. This reduction lowers the cost of purchasing new belts and results in a lighter overall product.

These advantages further contribute to a decrease in the main resistance components, significantly reducing investment costs and enhancing the overall efficiency of the entire system. TransEvo belts not only lower energy consumption across the conveyor system but also often result in lower initial investment costs compared to traditional belts.

TransEvo belts were first applied in open-pit lignite mines, where they handled sharp-edged materials. After further improvements, they were successfully implemented in underground mines as well. TransEvo-X belts provide a considerable enhancement in energy efficiency and comply with DIN 22131 and ISO 15236 “H”, while the latest TransEvo-V generation belts meet EN 14973 and EN 12881 standards [13].

2.1.3. Habasit Energy-Saving Conveyor Belts

Habasit’s energy-saving conveyor belts (Habasit International AG, Reinach, Switzerland), known as Eff-Line, are designed to significantly reduce energy consumption. The company has identified the friction coupler as a key factor affecting the energy use of conveyor belts. The accompanying figure illustrates where the most significant resistance can occur and indicates its maximum percentage share of the total resistance involved in conveyor movement.

Habasit has developed a special water-based impregnate that is applied to the running cover side of the belt. This treatment can lead to a reduction in energy consumption of up to 45%, which significantly decreases operating costs. The impregnated belts have lower sliding resistance, resulting in an extended service life. Additionally, energy-saving Habasit belts contribute to reducing the carbon footprint and generating less waste through fewer belt replacements. Overall, these advancements translate into substantial savings in operating expenses [14].

2.2. Variable-Frequency Drives (VFDs)

Adjusting the speed of belt conveyors in real time based on the load level or unit weight can significantly reduce energy consumption, especially when demand is low [15,16]. Research indicates that using variable speed adaptations to match changing loads can lead to energy savings of up to 20% [17].

Typically, belt conveyors operate at a constant speed, regardless of how loaded they are, as seen in mining operations transporting bulk materials. To enhance the energy efficiency of continuous conveying systems, variable-frequency drives (VFDs) can be employed. VFDs allow for real-time adjustments to motor speed based on operational requirements, resulting in substantial power savings at drive stations while preventing unnecessary accumulation of bulk materials. Studies show that energy savings are especially pronounced during periods of lower instantaneous mass outputs. When VFDs are used, the savings increase in proportion to the decrease in the flushing material [18].

2.2.1. ABB Variable-Frequency Drives

By adjusting speed in real time depending on the load level or unit weight, ABB (ABB, Oerlikon, Switzerland) variable-frequency drives (VFDs) optimize belt load by selecting the appropriate speed. Reference values are determined by a laser scanner that monitors the load. Smooth starting and braking result in lower wear on both the gear and the belt itself, eliminating belt slippage on the drive pulley and ensuring relatively even torque on pulleys. The system also monitors speed differences between engines installed on one drive pulley. The advantages of using this ABB solution primarily include energy savings, enabled by periods when the conveyor operates at a reduced speed. Other benefits are increased efficiency, reduced gear wear, and minimized system disruptions. Optimal use of the conveyor capacity and unit load of the belt is achieved by modifying the speed, ranging from 3.0 to 6.0 m/s. The system is equipped with a special laser scanner that provides information on the cross-section of the transported material, specifically the degree of filling of the belt basin with the material. This system is integrated with the control system, where reference values for individual conveyors are uploaded. The measurements are transferred to local controllers and then to frequency converters. The converter system allows for displaying and editing parameters (also in online mode), saving parameters, displaying signals in graphical form, logging errors, and creating reports [19]. Such a solution extends the service life of the conveyor components and reduces their energy consumption [20].

2.2.2. Integration with Automation Systems

Variable-frequency drives (VFDs) utilize specialized sensors and automatic control systems to respond to changes in conveyor load in real time [21]. By employing advanced technologies, such as artificial intelligence (AI) and machine learning, various control strategies and speed selection methods can be developed. One innovative approach involves using artificial neural networks to calibrate remote control systems; this not only reduces energy consumption but also increases conveyor throughput [22,23,24]. Researchers, based on a detailed analysis of the conveyor’s technological process and the electric drive with a frequency converter, have developed an automatic control system. They created a mathematical model and validated it through a simulation model. The solution proposed in their work is highly applicable [24].

2.3. Intelligent Monitoring and Alignment Systems

The incompatibility of various structural components in a conveyor system, like idler misalignments or belt deviations, can result in excessive and unnecessary energy consumption. Advanced monitoring systems for belt conveyors can identify these irregularities in real time during operation, aiding in maintenance planning [25]. The following subsections provide examples of solutions that facilitate this capability.

2.3.1. Voith’s BeltGenius ALEX

Voith’s BeltGenius ALEX (Voith GmBH, Heidenheim an der Brenz, Germany) is a system designed to analyze the alignment of carrying idlers in belt conveyors. When the sensors detect misalignment, the system reports the issue and suggests a solution. This helps extend the life of the idlers and reduces energy consumption by eliminating unnecessary increases in resistance caused by misaligned idler sets. Even a slight misalignment of the belt can lead to increased energy usage and may cause the transported material to spill over the edges of the belt, potentially resulting in downtime. Misalignment also accelerates drum wear, leading to additional costs associated with unplanned downtime and the need for replacement parts. These issues can be avoided by using the BeltGenius ALEX solution.

Measurement sensors are installed on both edges of the belt to assess the alignment of each outer idler in every idler set. All measurement data is recorded and stored, providing information about which idlers are improperly positioned, what alignment corrections are needed, and the direction of those adjustments. This equips the operator with clear insights into the current condition of the idlers and allows for comparisons with the intended model position. The system is versatile and can operate in mining conditions, making it suitable for all conveyor belts with a thickness greater than 30 mm. Implementing the BeltGenius ALEX can result in savings of over 10% in the total energy consumed by the conveyor and significantly extend the life of the idlers [26].

2.3.2. Non-Destructive Testing

Non-destructive testing techniques include vibration analysis of components, such as idlers, pulleys, and engines [27]; magnetic or visual detection of damage in steel cord belts [28]; and the inspection of conveyors using thermal imaging technology. These diagnostic tools enable the identification of elements that generate excessive motion resistance, which may manifest as overheating, increased noise, or unusual vibrations. By detecting these issues early, potential energy losses can be minimized [28,29], and failures can be prevented, allowing for the planned replacement of worn or faulty components [30,31].

Non-invasive diagnostics are also used for rotating elements like rolling bearings (Figure 1), which are found in idlers, on shafts, and within engines. Diagnosing bearings in engines is particularly challenging, as the measured signals can be affected by additional cyclic vibration signals. However, by employing advanced analysis techniques that focus on frequency and filtering out so-called noise, it is possible to identify faults in bearings even when significant signal components that may be characteristic of an undamaged element are present [27].

For belts with a core made of steel cords, non-invasive magnetic diagnostics can be employed. The belt passes between magnetizing panels and then underneath a reading panel. By analyzing how the magnetic field of the core changes, it is possible to assess whether the core is damaged and to what extent. This method is also effective for analyzing the geometry of the belt and diagnosing the condition of its connections.

It is beneficial to conduct simultaneous measurements using a visual camera, as some seemingly superficial damage may indicate serious issues in the core (such as corrosion of the cords), while extensive damage to the belt cover (like longitudinal cuts) might be relatively superficial. Ideally, the measurements should be taken in the lower run, where the belt is not transporting any material, or on the drum when the belt is flat [28]. Figure 2 presents a test rig equipped with both magnetic and vision modules for non-destructive testing.

Thermal imaging cameras can be used to diagnose various components of a belt conveyor, including pulleys, drums, gears, motors, and the belt itself. Measurements should be taken while the conveyor is in operation, ideally starting from the moment it is turned on, to effectively detect any temperature increases. It is advisable to perform these measurements at intervals, such as every few months, to monitor whether any components are experiencing higher temperatures than before. Effective thermal imaging diagnostics are comparative; for example, analyzing two identical conveyors operating under the same conditions and load would provide valuable insights. However, this can be challenging to execute. In the accompanying Figure 3, the temperature changes of individual gear wheels in a three-stage gear at the conveyor drive station are depicted. For clarity, it is recommended to measure the temperatures of two gears operating on the same drive drum shaft (double-sided driven) to ascertain if their temperature increases are similar. If they differ, it may indicate that one of the gears or its components is misaligned or experiencing greater load. This discrepancy can lead to increased concentrated resistances and subsequently higher power consumption [32].

2.4. Preventive Maintenance and Operational Good Practices

The operation of machines and devices that employ preventive diagnostics leads to more efficient performance. Without proper diagnostics and maintenance, or worse, running equipment until it fails, can lead to increased energy consumption, a shortened lifespan of the equipment, and unexpected emergency stops [33,34]. The key components of preventive maintenance and best operational practices include using high-quality lubricants, selecting the appropriate cleaning devices, training the crew effectively, and adopting an ecological approach.

2.4.1. Good Quality Lubricants

The maintenance of various components of a belt conveyor, such as bearings and gears, greatly relies on the quality and condition of the lubricants and oils used. Selecting the appropriate lubricant for the specific operating conditions of the conveyor is essential. Frost-resistant lubricants enable operation in sub-zero temperatures; however, during the summer months, they may create greater resistance to the rotation of the pulleys compared to traditional lubricants. For conveyors operating indoors, like those in airports and processing plants, or in underground mines, the temperature fluctuations are typically smaller, so the lubricant should be chosen based on these specific conditions. Additionally, it is important to remember that oil wears out over time, so planning for its replacement is crucial. If the replacement is not performed frequently enough, or if insufficient oil is applied to the pulleys, it can lead to damage that necessitates replacing the entire component. On the other hand, applying too much oil can cause excessive heat production, which is also harmful to the conveyors [35].

To establish a baseline for the acceptable decibel levels during the normal operation of the pulleys in good technical condition, several methods can be used:

• Baseline Creation During Oil Addition: Establish a baseline when adding oil. If the intensity of the decibel level decreases and then starts to increase, it indicates that no more lubricant should be added. At that moment, the measurement will be set as the baseline.
• Comparative Method: Analyze the decibel levels of several conveyors operating under similar (ideally equal) conditions and loads. If the difference between them does not exceed 8 decibels, this measurement can be considered as the baseline.
• Long-Term Analysis: Monitor the decibel levels over an extended period, such as a month. If there are no significant changes, or only slight variations, these levels can serve as the baseline for future comparisons [35].

Proper maintenance of the conveyor system helps minimize the resistance of the pulleys to rotation, thereby reducing energy consumption. Moreover, well-maintained pulleys can have a significantly extended lifespan.

2.4.2. Properly Selected Cleaning Devices

Properly chosen conveyor belt cleaning devices specific to different materials, such as bulk goods, mud, or those used in the cement industry, can enhance the friction between the belt and the drive pulley, thereby preventing slippage [36].

Figure 4 illustrates a highly wear-resistant ceramic belt cleaner that can withstand high temperatures. Due to its unique properties, it is suitable for use in the steel and cement industries, where elevated temperatures are common. This solution can be implemented across various high-speed conveyors, resulting in an extended lifespan for specialized belts [36].

Another interesting solution provided by the same manufacturer is the water removal cleaner (see Figure 5). Belts that transport sticky materials or mud should be cleaned regularly to ensure effective removal of these substances. Secondary cleaning is achieved using a special scraper, which is a replaceable component. The metal parts of the scraper are either galvanized or made of stainless steel, preventing corrosion and extending the service life. This feature is especially important for devices that clean belts used with wet materials [36].

2.4.3. Operational Good Practices

Monitoring the wear of conveyor components is one of the most important operational best practices. Unfortunately, many plants continue to operate conveyors until a breakdown occurs, leading to unplanned downtimes that reduce the efficiency of the transport system and incur additional costs. In some cases, companies replace operating parts that are subject to wear on a cyclical basis. However, if replacements are made according to a schedule rather than the actual technical condition of the components, it can result in unnecessary expenses. This is due to replacing parts that may still be in good working order, resulting in waste. The most cost-effective approach is to perform maintenance and replacements based on diagnostic data, specifically, the actual condition of the components. By planning the replacement of worn parts and anticipating potential failures, companies can prevent unnecessary downtime [37]. An important aspect of effectively managing belt conveyors is load balancing and scheduling transport tasks during off-peak hours to optimize energy consumption. It is advisable to avoid operating an empty or lightly loaded conveyor, as this leads to unnecessary power consumption and results in low efficiency for the transport system. Consequently, this type of operation is economically unviable [38]. The assessment of energy consumption classes for machines and devices is gaining popularity, and many countries are implementing regulations and conducting inspections of companies in this area. Periodic energy audits will ensure that belt conveyors comply with energy standards and are making optimal use of their designed system capacity. These audits will identify areas that need improvement and provide staff with education on energy reduction strategies [10,20]. Training and education for both management and employees on best practices and principles of energy savings, as well as monitoring the proper operation of conveyors, are essential [8].

2.4.4. Refurbishing or Recycling

Refurbishing and Recycling Services: Companies like MoorMarine (West Perth, WA, Australia) specialize in recycling both textile and steel cord conveyor belts. They conduct on-site assessments at the plant to evaluate the condition and weight of the belts. These companies arrange transportation to partner belt processing facilities and, in some cases, organize the export of used belts to other countries. They classify the belts and determine whether they can be regenerated, recycled, or need to be crumbed if they are of low quality.

The recycling process can transform the belts into various products, such as idler elements, soft bricks, or shoe soles. These sustainable solutions align with the principles of the circular economy and help minimize the carbon footprint [38].

2.5. Automation and Smart Technologies

The integration of intelligent technologies and machine automation is transforming various industries, particularly in the management of belt conveyors. Real-time monitoring of operations and the technical condition of these systems relies heavily on the latest technological advancements.

2.5.1. Integration of AI and IoT

The Integration of AI and IoT: Today, conveyor belts are equipped with numerous sensors and can utilize both IoT (Internet of Things) technology and AI (artificial intelligence) algorithms simultaneously. These advanced conveyors are referred to as “intelligent conveyors” because they can adjust their operating parameters based on the data collected. This capability enhances their efficiency, makes operations more economical, and reduces energy consumption [39,40].

Cyber-physical systems (CPS), connected to IoT and IoS, create a network where information from various sensors is continuously processed and communicated to the device interface. CPS combines computation, communication, and control. The first generation of such systems included identification technologies like RFID (radio frequency identification) sensors, which made it easy to identify devices and monitor their condition. The next generation added sensors and actuators with basic functions.

Currently, CPS can store, analyze, and process data on a large scale, equipped with various sensors that monitor operational parameters and the technical condition of components in real time. An intelligent conveyor operates based on two-way communication facilitated by an implemented data transfer protocol [41]. Figure 6 below illustrates a smart monitoring system for conveyor belts, highlighting sensor-based data acquisition and communication pathways essential for optimizing operational efficiency and enabling energy-saving control strategies.

2.5.2. Digital Twins

Digital twins are virtual replicas of real machines or transport systems, such as belt conveyors. They enable the simulation of various operating conditions, including load and speed, and allow for the analysis of how external factors, like temperature, impact the machine’s operation and efficiency. By using digital twins, it is possible to identify the most economical operating mode before the conveyor is put into operation. This technology creates new opportunities to enhance the efficiency and durability of conveyors [42,43,44].

Digital twins of belt conveyors facilitate the design of the most economical and energy-efficient variants while also enabling the ongoing assessment of the conveyor during its operation. This technology continuously checks that everything operates in accordance with the design specifications. Utilizing such a solution allows for a seamless integration of transport system operations and maintenance while enabling adjustments to operating parameters and planning for modernization based on actual conditions. Real-time performance, driven by complex algorithms, accelerates the decision-making process and enhances accuracy. The foundation of these sophisticated systems is the creation of a digital model derived from the most precise data. Continuous validation ensures that this digital model accurately represents the physical conveyor and is responsive to variable external factors, as well as the operational parameters of the conveyor itself [44].

2.5.3. Remote Monitoring and Control Systems

Currently, continuous control systems for belt conveyors monitor their efficiency by evaluating operating parameters in real time [10]. This real-time assessment allows for the detection of any inefficiencies. Predictive algorithms play a crucial role in optimizing conveyor operation, which in turn reduces power consumption [16]. By monitoring the technical condition of the system, these algorithms help prevent failures and unplanned downtime. This proactive approach enables maintenance and component replacements to be scheduled, allowing transport systems to maintain their intended efficiency. Ultimately, data-driven maintenance scheduling minimizes unplanned downtime and ensures that the system operates at peak efficiency [45].

2.6. Design Optimization

It is important to recognize that the most significant factors influencing the energy consumption of belt conveyor transport systems are their design and operating parameters. Numerous studies highlight that elements such as the materials used, the design and efficiency of the drive station, the selection of lubricants, and the quality of the rollers can all impact the energy consumption of belt conveyors [1,3]. To optimize the efficiency of conveyors, the specific energy consumption (SEC) indicator is particularly useful when analyzing and designing continuous haulage routes. There are cases where conveyors with higher power consumption might be more economically viable due to their greater efficiency [10]. Each component of a conveyor generates a certain amount of motion resistance, making it essential to analyze various operational scenarios carefully to achieve the most optimal design. A well-designed belt conveyor can significantly lower the carbon footprint of the entire conveying system. Optimized belt conveyors often feature fewer transfer points, carefully designed inclined sections, and sometimes incorporate modular solutions [17,46,47]. It is advisable to design conveyors with economically justified lengths and, whenever possible, to minimize their inclination. Using lighter materials for the construction of conveyor components is beneficial, and frames can be crafted from composite materials. Energy recovery systems on descending sections, known as gravity-assisted systems, have been utilized for years to reduce the energy consumption of motors driving the conveyor on downhill sections. These systems allow for energy recovery [17]. To facilitate this, motors must be equipped with regenerative drives, which convert kinetic energy into electrical energy. This electrical energy can then be fed back into the grid and reused by the conveyor drive [16].

3. Applicability of Energy-Saving Solutions Based on Conveyor Type and Application

3.1. Implementation Challenges of Energy-Saving Technologies

Many energy-saving solutions have been used for years and new technologies continue to emerge; however, their effectiveness and usability can vary depending on the specific conveyor on which they are installed. This is influenced by the length of the conveyor, the capacity, and external factors, often depending on the environment in which the conveying system is operating. It is important to analyze the benefits, potential losses, and the reasonableness of the application of a given solution. This section provides a critical review of the solutions described in the previous chapter, while also indicating which solutions are most suitable for high-capacity, long-range mining conveyors and those better suited to conveyors with lower technical parameters, such as shorter lengths, lower loads, or indoor operation. Below are selected technologies whose use is not always economically justified, or which may sometimes be problematic to use.

• Habasit Eff-Line belts, which can reduce the energy consumption of a conveyor by up to 45%, are designed for medium or short conveyors operating in closed areas (warehouses, airports, or processing plants) where belt speeds are moderate.
• VFD solutions are the most cost-effective in conveying systems that operate with a traveling load, such as bulk material conveyors in underground and open pit mining, where dynamic speed control is beneficial due to the variable degree of conveyor loading. In the case of short, low-capacity conveyors operating with a constant load, the return on investment in VFD systems may be limited.
• Real-time alignment systems (e.g., BeltGenius ALEX by Voith), similarly to non-invasive diagnostic systems, generate the greatest benefits (in particular, extension of component lifetime and lack of unplanned downtime) in the mining industry. In the case of conveyors, for which failures caused by unplanned downtime can be associated with huge financial losses for the company. In turn, their use may not be justified conveyors with a low risk of failure.

The technologies discussed undoubtedly have many advantages, but introducing new solutions, especially to existing systems, is not without challenges. The main problem is often the high initial investment cost, especially in the case of advanced monitoring systems, VFD and automation technologies. In the case of short-term investments, this can discredit some solutions. Integrating systems with existing infrastructure often requires customization, modernization, and sometimes downtime for installation. Using automation-related systems or creating digital twins requires specialized knowledge, sometimes training staff or hiring external contractors. To minimize problems, a gradual implementation strategy is recommended, as well as analyzing whether a given solution is cost-effective in a specific case.

3.2. Comparative Evaluation of Energy-Saving Technologies for Belt Conveyors

In order to consciously use available energy-saving solutions, it is good to analyze conveyor transport systems individually, comparing the possible benefits with the limitations of their implementation.

Table 1. Comparative assessment of selected energy-saving technologies in belt conveyors.

Technology	Energy Savings [%]	Best Application Context	Implementation Complexity	Key Benefits	Main Limitations
Amp Miser® belts (Forbo, Siegling GmbH, Lilienthalstrasse, Hannover)	Up to 50% [12]	Long conveyors, indoor conveyors	Low	Low friction, TÜV certified, long belt life	Limited applicability in harsh environments
TransEvo® belts (Semperit Group, Vienna, Austria)	Up to 25% [13]	Mining	Medium	Lower rolling resistance, lighter belts, mining-ready	Higher material cost; mining-specific implementation
Eff-Line (Habasit International AG, Reinach, Switzerland)	Up to 45% [14]	Indoor conveyors	Low	Lower sliding resistance, water-based impregnation	Less suited for high load, outdoor conveyors
VFD Systems (ABB, Oerlikon, Switzerland)	Up to 20% [19]	Variable-load, high-capacity conveyors, mining	High	Real-time speed control, less wear, scalable	High upfront cost, complex integration
BeltGenius ALEX (Voith GmBH, Heidenheim an der Brenz, Germany)	~10% [26]	Long conveyors, mining	Medium	Misalignment detection, extends idler life	Requires sensor installation and integration
Non-Destructive Testing Systems	Indirect [28,29,31]	Steel cord belts, safety critical systems, mining	High	Prevents failures, extends component lifespan	Signal acquisition, training-intensive
Digital Twin and IoT-based Systems	Indirect but significant	Complex, integrated conveyor systems, mining	Very high	Predictive maintenance, operational simulation	Requires fully digital infrastructure

below presents a multi-criteria comparison of selected energy-saving technologies, indicating what maximum energy savings they can offer, where to use them, and their main limitations.

Only technologies for which quantitative data was available were used to develop the table, allowing for the determination of the degree of energy saving and the creation of a standardized comparison. Solutions such as cleaning devices and the type of lubricant used are, of course, important, but they were omitted from the table due to the lack of available specific data enabling comparison with other solutions.

4. Results—Environmental and Economic Benefits

Minimizing carbon footprints and implementing environmentally friendly solutions are becoming essential obligations for companies today. Belt conveyors are fundamental for continuous transport in various industries, especially in mining. However, modernizing all types of conveyors is crucial. Solutions that reduce power consumption or extend the service life of conveyors are both environmentally friendly and economically beneficial in the long run [48,49]. It is clear that lowering the energy intensity of conveyor transport systems directly leads to a reduction in greenhouse gas emissions, aligning with sustainable development goals and holding particular importance for mining companies [50]. Achieving these solutions requires a comprehensive, multi-faceted approach. As discussed in the previous chapter, it is vital to seek solutions that minimize motion resistance, prolong the lifespan of conveyor components, optimally manage efficiency, and analyze real-time collected data holistically. These strategies can significantly reduce both energy consumption and waste generated by damaged elements [16,42,50].

In today’s world, minimizing the carbon footprint and implementing environmentally friendly solutions is becoming an obligation for companies, not just a choice [51]. Belt conveyors are a fundamental means of continuous transport in many industries, particularly in mining. However, it is essential to modernize all types of conveyors. Solutions that reduce power consumption or extend the service life of conveyors are both environmentally sustainable and economically beneficial in the long run [38]. Reducing the energy intensity of conveyor transport systems directly leads to a decrease in greenhouse gas emissions, aligning with sustainable development goals and being particularly important for mining companies. Achieving these solutions requires a complex, multi-faceted approach. As discussed in the previous chapter, it is crucial to seek solutions that minimize motion resistance, extend the life of conveyor components, optimize efficiency, and analyze real-time collected data holistically. These efforts can significantly reduce the energy consumption and waste generated by damaged components [48,49,51].

Reducing energy consumption and waste generation leads to significant savings. Furthermore, companies that implement energy-saving solutions will be better equipped to handle potential increases in energy prices. The solutions outlined in the Section 2 enhance the energy efficiency of conveyor transport systems, minimize environmental impact, and provide both financial and reputational benefits for businesses [8].

5. Future Research Directions and Development Perspectives

The widespread adoption of energy-saving and environmentally friendly solutions is a reality that continually drives development in this field. One of the key aspects of efficient conveyor use is optimizing performance by adjusting the speed based on the material flow rate. This approach is crucial for energy savings and represents one of the most significant advancements in conveyor technology [17]. Although this aspect is well known, modern control algorithms continue to uncover increasingly effective solutions. The operational efficiency of belt conveyors can be enhanced through various optimization techniques, and this focus on optimization, along with the system’s ability to respond in real time, is a key area of ongoing development [3].

Fuzzy PID control solutions can be applied to belt conveyor control systems, reducing operational risks, while modern control systems can enhance energy management [10].

Non-destructive diagnostic systems are becoming increasingly important for monitoring belt conveyors. In recent years, the use of non-invasive diagnostic tools has emerged as a key development in this field. It is now essential to find economically viable solutions that can continuously measure both the technical condition and operating parameters of the conveyors, while taking into account various internal and external factors (such as atmospheric conditions) [29]. While there are existing solutions, future research should focus on enhancing integrated systems that can simultaneously monitor different components, facilitate information exchange among these components, and make real-time decisions based on a holistic assessment. Digital twins of belt conveyors are already in use, but they are continually being refined through advancements in machine vision and artificial intelligence algorithms. Looking ahead, a significant goal is to develop a digital twin that encompasses the entire transport system or even the whole mine. This digital twin should be continuously validated against actual processes and possess the ability to predict potential events, such as failures or overloads within the transport system [44].

The final, yet equally important, direction for development is the technology that facilitates the alternative use of worn-out parts or components of belt conveyors. The closed-loop economy is a key component of the zero-waste policy and has become increasingly essential today. This necessity arises not only from the direct benefits to companies but also from the rapidly changing environmental landscape [8]. Recycling of various components has been practiced for years, with companies dedicated to finding reusable or recyclable materials, such as those from conveyor belts [38]. However, worn-out parts from belt conveyors still produce a significant amount of waste, and new solutions for their reuse continue to be actively sought.

6. Conclusions

Belt conveyors are essential systems for continuous material transport and often represent the most economical solution for many companies. However, they also consume significant amounts of energy. These conveyors are widely used for the continuous transport of bulk materials and various goods in industries such as logistics and production.

Modernizing existing conveyors and designing new ones in line with current trends can yield numerous benefits. Reducing the energy consumed by conveyors and improving the energy efficiency of entire transport systems present both technical and strategic challenges, especially in light of increasingly strict environmental protection regulations imposed on businesses.

This article reviews the latest energy-saving design solutions. These include conveyor belts designed to produce lower movement resistance, the use of variable-frequency drives (VFDs) that adjust speed according to the immediate conveyor requirements, and the implementation of intelligent systems for real-time monitoring of operational parameters and the technical condition of conveyors.

To maximize the optimization of operational parameters, all systems should work together to detect inefficiencies, propose modifications in real time, and forecast maintenance and component replacements. A holistic approach to transportation tasks, along with collaboration among algorithms and two-way data exchange, is essential to achieving this.

In addition to utilizing cutting-edge energy-saving solutions, optimal conveyor design and strict compliance with system guidelines are critical. Whenever possible, areas of increased resistance, such as transfer points, should be minimized, and solutions for energy recovery on descending conveyor sections should be employed.

While the incorporation of new technologies, conveyor sensors, and real-time monitoring may lead to higher initial costs, as shown in the Section 4, the long-term advantages significantly outweigh these expenses. These innovations reduce energy consumption and, subsequently, operational costs. Furthermore, they extend the lifespan of conveyor components and substantially decrease their carbon footprint, rendering them more sustainable and environmentally friendly.

In conclusion, modernizing and designing sustainable, energy-saving belt conveyors has become not only a strategic advantage for companies but also a necessity imposed by increasingly stringent environmental regulations regarding energy consumption.

Companies that keep pace with these developments by implementing more sustainable and energy-saving solutions—and focusing on the principles of a circular economy—are better positioned to comply with strict legal regulations. They can achieve cost savings and improve their reputation among consumers, potential clients, and business partners.

The use of energy-saving solutions in belt conveyors is consistent with the ESG (environmental, social, and governance) principles that should guide entrepreneurs in all industries. The technologies presented in this article are environmentally friendly because they reduce energy demand, greenhouse gas emissions, and material waste. Increasing the reliability of belt conveyors and preventive diagnostics will increase work safety and reduce unplanned downtime. Real-time management and optimization of conveyor operation makes these systems ready for potential audits because they comply with regulations, such as ISO 50001 [51], and fit into the decarbonization plans of companies. The sustainable use of conveyors and their reasonable modernization is undoubtedly technical and economic progress but also a strategic response to global ESG expectations.