Light Unmanned Aerial Vehicles (UAVs) for Cooperative Inspection of PV Plants

An early field trial of thermal plus visible PV plant inspection with two cooperating UAVs: a large fixed-wing for overview and a small electric multirotor for close-up. On a 200 kW, 810-module plant in northern Italy it found hot spots, shading and cracked cells, a broken glass and snail trails, with GPS-tagged images to locate faulty modules. The authors estimate system cost below 5% of annual maintenance cost for 0.2-1 MW plants, as a preliminary figure.

Key findings

• Test site: 200 kW, 810 polycrystalline modules, northern Italy
• Detected hot spots, shading/cracked cells, glass breakage and snail trails
• Overview aircraft was too far to diagnose some hot areas; close-up multirotor needed
• Estimated cost below 5% of annual maintenance cost for a 0.2-1 MW plant (preliminary)

Limitations

• Single plant; authors call it a preliminary validation
• No detection rates, altitude or inspection-time figures reported
• Fault cause still needed visual confirmation; automatic defect linking left to future work
• Requires civil aviation permits