All objects emit invisible infrared energy. Solar power plant owners can now use DJI Mavic 3T thermal inspection drones to precisely capture detailed temperature information for each cell in a solar panel through infrared thermography. Aerial thermography is an economical, fast, and precise method for solar PV inspection.

What are the main defects identified by aerial infrared thermography?

Inspections with the naked eye can only identify dust and other physical deficiencies within panels. Current types of defects that drone technology can detect and report as a result of thermal inspection include:

- Cell error
- Module connection error
- Cracked panel error
- Diode/Soldering fault
- Delamination
- String error
- Ghosting error

Most photovoltaic panel manufacturers guarantee 90% efficiency over 10 years and 80% efficiency over 25 to 30 years. However, as the panel ages, gradual degradation occurs. Abnormal weather conditions (lightning, storms), cell overheating, and malfunctions of other components can also lead to hot spots in the PV panel.

Loss of high efficiency in PV panels.

Each type of fault results in an energy loss ranging from a few % of production to complete panel failure. Depending on the facility, these faults can lead to a production shortfall of up to 45% in the most critical cases.

Photovoltaic panels emit a certain amount of heat, and it turns out that faulty panels give off more heat than functional panels. The temperature difference can be easily detected using an infrared thermal imaging camera. A quick drone flyover equipped with a thermal camera can rapidly and cost-effectively identify faulty panels, allowing operators to replace panels and maintain the solar farm in operation with maximum efficiency.

It is crucial for all cells to work together to efficiently produce maximum output energy. When individual cells are damaged due to manufacturing faults or external incidents, the output power decreases, and efficiency drops. Unfortunately, these problems are extremely difficult to see with the naked eye, and the only way to test panel efficiency is by voltage readings. Therefore, if we do not test every part of the solar power plant, which can be enormous considering each string can have up to 15-20 panels, and some locations may have thousands of strings, we turn to infrared thermography. Infrared thermography has the ability to see the thermal difference between solar cells and can be used to determine whether any of these cells are damaged or faulty.

Aerial thermography with Drone Technology.

Our aerial thermography service adheres to global standards. Aerial thermography is the fastest and most cost-effective method for detecting performance issues in a solar power plant and improving plant efficiency. Through our drones, an entire 100 MW solar power plant covering 200 hectares can be surveyed within 4 to 5 days.

All collected and analyzed data is compiled into a report that helps solar power plant owners better understand where to direct teams for critical repairs.

Our reports show anomalies categorized from major to minor, providing a clear overview of different found errors and how common they might be.

The costs of conducting thermal scanning are small compared to the results and benefits that can be achieved. Results of infrared thermal imaging on PV panels can lead to significant savings for solar power plant owners.

Visual inspection with a drone.

Another issue to pay attention to is obstacles and debris, such as dirt and snow, and shadows from objects around the solar array, which can cause a cell to become negatively biased. Objects such as leaves, dirt, and snow can not only cause a significant reduction in production but can also pose a fire hazard. Using high-definition cameras with a drone allows for quick and efficient visual inspections in real-time or after the mission using processed images in various formats, including photos and videos, orthorectified maps, and digital terrain models.

The frequency of solar panel inspections depends on several factors, including the type of solar power plant, its location, and the environmental conditions in which it operates. However, a general recommendation is that drone-based solar panel inspections should be conducted at least once or twice a year. Regular inspections can help identify problems early, enabling proactive maintenance measures and preventing costly repairs or system downtime.

Factors influencing the frequency of inspections:

1. Environmental conditions: Solar panels in areas with high levels of dust, debris, or pollution may require more frequent inspections to ensure they remain clean and operate optimally.

2. Weather events: Solar panels exposed to severe weather conditions, such as hailstorms, strong winds, or heavy snowfall, should be inspected more frequently to assess potential damage and promptly address issues.

3. Age of the solar installation: Older solar installations may experience more wear and degradation over time, requiring more frequent checks to maintain optimal performance.

4. Manufacturer recommendations: Some solar panel manufacturers may have specific guidelines for inspection and maintenance that should be followed to ensure proper functioning and compliance with warranties.

By conducting regular drone-based inspections of solar panels, owners of solar energy systems can ensure optimal performance, extend the lifespan of their panels, and maximize return on investment.