2025 Case study

Thermal Drone Inspection of Merredin Solar Farm

Risen Energy Merredin Solar Farm

On 8 July 2025, Remote Ag Solutions performed a drone-based thermal inspection on a small designated area in Merredin. This inspection was successful in identifying possible fault points in an efficient and timely manner, giving Risen Energy enough time to rectify issues before they became costly and dangerous.

During this inspection, a targeted thermal inspection was commissioned at Risen Energy’s Solar Farm to validate asset health, quantify performance risks, and prioritise maintenance within a designated section. Using high-resolution, drone-mounted thermography under uniform irradiance and stable weather conditions, the survey combined systematic aerial capture with post-flight analysis against baseline thermal profiles to surface fault modes that materially impact yield, safety, and asset longevity.

Introduction

Remote Ag Solution is a specialist in remote sensing and decision support, transforming field data into actionable maintenance priorities for asset-intensive operations. Deliver fast, accurate visibility of asset health so owners can recover yield, reduce risk, and deploy resources where they matter most. We combine calibrated aerial thermography, RGB imaging, and disciplined analytics to identify fault modes, score severity, and localise root causes with geo-referenced precision. The end-to-end service shortens fault-detection intervals, accelerates remediation, and verifies outcomes through repeat surveys. By minimising site disruption while maximising diagnostic clarity, Remote Ag Solution strengthens availability, extends asset life, and supports defensible, investor-grade governance across energy, agriculture, and other infrastructure portfolios worldwide.

Background

The inspection was carried out using a DJI M4DT drone fitted with a high-resolution thermal imaging sensor. This technology enabled real-time data collection during flight and detailed post-survey analysis afterwards. The inspection was performed under stable weather conditions with uniform irradiance, ensuring that observed anomalies were not influenced by shadows, fluctuating irradiance, or external temperature variations.

The process followed a systematic flight path to guarantee full coverage of the designated section. Thermal images and videos were captured at appropriate altitudes and angles to balance resolution with area coverage. Following the flight, the data was processed with advanced analysis tools that compared results against baseline thermal profiles for healthy modules. This methodology ensured that deviations were clearly distinguished from normal operating signatures, allowing for accurate identification of fault types

Methodology

Fault modes identified and their operational Risks

The inspection has shown that faults existed in the area that was surveyed by Remote Ag Solutions. The business operations of each issue present separate risks for operations and commercial activities.

The problems generate avoidable energy losses, which simultaneously produce dangerous heat conditions that threaten system components until they shut down unexpectedly, thus causing financial losses.

The detection of multiple bypassed substrings became possible because researchers found regular rectangular zones of abnormal temperature. The affected substrings operate as independent units, which reduces panel output by one-third while increasing localised heating risks that become more severe when multiple arrays are connected.

Bypassed Substrings

The cell group contained a hot spot, which produced heat in a particular area because the bypass diode had failed. The heat produced in this specific area threatened the module structure while shortening its operational lifespan.

Single Hotspot from Bypass Diode Failure

Potential Induced Degradation (PID)

The temperature readings between adjacent panels showed patterns that corresponded to the leakage current behaviour resulting from the voltage. The modules that experience PID problems demonstrate both decreased conversion performance and faster deterioration, which shortens production duration and operational lifespan.

String Failures – Open Circuits

The entire string showed lower temperatures than its neighbouring strings, which indicated that the string wiring or connectors had become open circuits. The strings that get affected lose their entire output, which results in an instant decrease in yield performance.

(PID + Open Circuit) Fault Analysis

RECOMMENDATION, PRIORITISATION AND PERFORMANCE IMPACT

  • The system needs immediate corrective measures to handle its most critical system issues. Faulty bypass diodes should be replaced as a priority to eliminate the overheating risk posed by the hotspot. The assessment of open-circuit string failures needs to start with an on-site evaluation before technicians can fix wiring or connectors to restore production levels. The assessment of PID requires electrical testing to determine its presence and the implementation of grounding improvements and insulation enhancements for slowing down the degradation process.

  • The modules that show damage need cleaning operations first before inspectors can conduct thorough visual examinations to detect hidden micro-cracks and dirt accumulation that could reduce their operational performance. The entire module needs to be replaced when system failures become unavoidable because degradation has reached an unfixable point.

  • Long-term monitoring needs to receive additional support. The company needs to conduct thermal inspections at higher frequencies in areas with known defects to track defect progression and stop faults from worsening. A dedicated fault database that tracks anomalies, inspection results, and repair activities will enhance preventive maintenance planning and decrease the occurrence of repeated failures.

Supporting Evidence

Each of the identified defects has been documented in the supporting thermal analysis report, which contains annotated images, temperature profiles, and comparisons with baseline conditions. The findings are consistent with known photovoltaic system failure modes and align with international diagnostic standards such as IEC 62446 for PV system testing and maintenance. Importantly, the results indicate that these are emerging faults rather than long-standing issues, making early intervention particularly valuable.

Conclusion

The July 2025 inspection of the Merredin solar farm conducted by Remote Ag Solution revealed a range of performance-impacting anomalies, including bypassed substrings, a diode failure hotspot, PID across multiple modules, and open-circuit string faults. Accordingly, these issues illustrate both immediate and long-term threats to the efficiency, reliability, and safety of the array.

By acting swiftly on high-priority findings and adopting a proactive monitoring strategy, Risen Energy can restore lost capacity, prevent further degradation, and extend the operational lifespan of the solar farm. This case highlights the critical role of thermal drone inspections in solar asset management, offering fast, non-invasive detection of hidden faults and providing the insights necessary for data-driven maintenance strategies.