The mining industry has traditionally relied on diesel generators to power off-grid infrastructure, including critical communication systems. However, this approach is costly, unsustainable, and subject to supply chain risks. Solar power has emerged as a preferred option for mining companies due to lower costs, reduced emissions, and increased energy independence.

Australia is rich in solar resources, especially in its mine sites located in semi-arid to arid regions such as the Pilbara, where dust and minerals are prevalent both naturally and through human activities.

Maintaining the efficiency of solar panels in these regions requires an effective solution for dust cleaning.

The reliability of solar power supply to critical infrastructure hinges on the maintenance of solar arrays. Dust accumulation on panels can reduce efficiency and reliability, leading to communication failures and production losses. Manual cleaning is expensive, labour-intensive, and poses risks to workers. An effective automated or remote preventative maintenance program for dust removal is necessary.

Effects of Mineral-rich Dust Soiling on Solar Panels in the Mining Sector

Faults in solar PV systems can significantly impact their power generation capability, leading to reduced output or even panel damage.

Solar panel faults, especially soiling and hotspots, are prevalent in the Pilbara region of Australia due to the high concentration of dust and minerals.

• Hotspots can occur when soiling causes local shading on solar panels. This shading causes the affected cell to act like a resistor, leading to an increase in heat and a decrease in efficiency. Over time, this can cause damage to the panel [2].
• Soiling also reduces the amount of sunlight that reaches the cells, leading to decreased power production.
• Soiling can lead to corrosion on the metal framing and internal circuitry, as well as oxidation of PV coatings, further impacting the panel's performance.
• Soiling can also lead to abrasions of the glass panel and antireflective coating when removed by mechanical cleaning, particularly when the dust has consolidated and adhered to the panels through cementation and/or caking.

Optimal Cleaning Frequency of Solar Panels in Active Mine Areas

Effective and reliable mine production operations rely heavily on solar power systems that power remote communication base stations. As such, preventative cleaning of solar panels is crucial to ensure the efficiency and reliability of these systems.

Recommended preventative maintenance schedule should include weekly cleaning of solar panels, with immediate cleaning following a dust storm in arid regions prone to high dust disturbance. This is particularly vital in areas close to mine site haulage roads, stock piles, production, and loading facilities where plant and equipment can cause dust disturbance.

To enhance the reliability of the solar power supply in active mine areas, given the significant amount of dust disturbance and the critical role of power supply in mine production, the recommended preventive maintenance program for solar panels in active mine areas includes daily cleaning.

HSE Risk

Maintenance and cleaning of soiling is time-consuming and costly, and in some cases, requires specialised equipment or personnel. Additionally, in remote or hard-to-reach locations, regular manual cleaning of the panels can be hazardous and costly for the operator and is not an effective use of onsite skilled resources.

Manual cleaning of solar panels is an unpleasant and hazardous task for mine workers. A manual water-based broom cleaning system will also damage the solar panels with cracks of the glass panels and abrasion of the anti-reflective coatings.

The following risks are associated with manual cleaning of solar panels:

• Muscle strains
• Heat exposure
• Working from heights
• Mobile plant, vehicle
• Exposure to high dust levels
• Slip and falls
• Use of hand tools
• Electric shock
• Adverse weather conditions
• Damage to environment (chemicals)
• Damage to solar panels

Autonomous Cleaning Robotics for Preventative Maintenance

Autonomous solar cleaning robots can be programmed for daily cleaning as an autonomous preventative maintenance program of solar arrays. The use of an autonomous dry cleaning robot for preventative maintenance eliminates the HSE risks associated with manual; cleaning.

Western Australian Tech company, Solar Energy Robotics, have worked with the Australian mining industry to design the Autonomous Solar Cleaning Robot (ASCR) specifically for reliable application in remote and harsh environmental conditions. The product is designed to clean small solar arrays power critical infrastructure in active mine areas.

IES has been supplying ASCR in the mining sector since 2018 and continuously maintains fleets of vehicles on sites. Our partnerships in the mining sector has led to increased reliability, efficiency and cost savings, which has resulted in high customer loyalty.

The ASCR is a water-less and chemical free cleaning solution that autonomously removes the dust before it consolidates and ‘cakes’ on to the panel. Caking occurs when dust accumulates on the panel, combines with moisture and dew, typically overnight and then dries in the morning sun. The dust is highly abrasive and damaging to the anti-reflective coating when it is removed.