The photovoltaic power plant inspection report meets the material, technical, personnel and software requirements for a quality output used to identify module and cell faults by drone-based thermography of photovoltaic systems in accordance with IEC TS 62446-3.
Overall assessment
20
Total anomalies
across 2 jobs
High
Overall severity
2× High · 1× Medium · 17× Low
3
Anomaly types
60
Modules detected
A total of 20 anomalies were found on 20 modules of the inspected photovoltaic power plant.
The total estimated annual power loss is 2,216.64 kWh.
Client
NameJana Kolářová
AddressVlčková 177, Vlčková, 76319, CZ
Phone+420 608 050 226
E-mailj.kolarova8@seznam.cz
Inspection processor
CompanyDroneTech s.r.o.
Legal addressVavrečkova 7074, Zlín
IČO19358041
DIČCZ19358041
Pilot
NameLukáš Bednařík
Phone+420604204639
E-mailbednarik@dronetech.cz
Drone operator No.CZE-RP-vfetdp3qviw0
Analysis processor
CompanyDroneTech s.r.o.
TechnicianLukáš Bednařík
Phone+420 604 204 639
E-mailbednarik@dronetech.cz
Power plant
Power14
Modules (number of modules)60
StructureStřešní konstrukce
Weather
Humidity51
Temperature27,4
Wind speed0
Intensity of solar radiation829
Cloud coverJasno
Inspection
Inspection typeDefault
Overall assessment
20
Total anomalies
across 2 jobs
High
Overall severity
2× High · 1× Medium · 17× Low
3
Anomaly types
60
Modules detected
A total of 20 anomalies were found on 20 modules of the inspected photovoltaic power plant.
The total estimated annual power loss is 2,216.64 kWh.
Each box shows the anomaly number(s) used in the table below; the key above maps every number to its anomaly type.
Each box shows the anomaly number(s) used in the table below; the key above maps every number to its anomaly type.
Overall assessment
Anomaly name
Number of anomalies *(1)
Number of modules *(2)
Estimated power loss (kW) *(3)
Estimated power loss (%) *(4)
Estimated annual power loss (kWh) *(5)
Soiling
17
17
1.98 kW
14.17 %
1,983.33 kWh
Bypass diode
2
2
0.16 kW
1.11 %
155.54 kWh
Cell overheating
1
1
0.08 kW
0.56 %
77.77 kWh
Total
20
20
2.22 kW
2,216.64 kWh
*(1) Anomaly: Number of occurrences of a given anomaly type.
*(2) Modules: Number of modules affected by the given anomaly type.
*(3) Estimated Power Loss (kW): The estimated power loss is defined as the product of the number of affected modules, the plant's peak power (STC), and the anomaly-specific performance impact factor (on a scale from 0 to 1).
*(4) Estimated Power Loss (%): The estimated power loss expressed as the ratio of the lost power to the plant's total capacity, shown in percentage terms.
*(5) Estimated Annual Power Loss (kWh): The estimated annual energy loss in kilowatt-hours, calculated as the power loss multiplied by the number of solar hours per year.
Anomaly breakdown
20
Total anomalies
0
Critical
2
High
1
Medium
17
Low
3
Anomaly types
#
Primary image
Secondary image
Anomaly name
Row
Position
AI Job
ΔT
Max °C
Min °C
Mean °C
Priority (Severity)
Recommended next step
1
Soiling
2
1
AIR-2026-001077
3.9
44.5
21.7
41.2
Low
Repair
2
Soiling
2
2
AIR-2026-001077
3.8
44.5
19.9
41.2
Low
Repair
3
Soiling
2
5
AIR-2026-001077
7.5
47.9
19.0
42.1
Low
Repair
4
Soiling
2
6
AIR-2026-001077
3.5
44.0
15.5
41.3
Low
Repair
5
Soiling
3
1
AIR-2026-001077
5.3
45.8
19.9
41.6
Low
Repair
6
Soiling
3
2
AIR-2026-001077
3.9
44.3
20.0
41.5
Low
Repair
7
Soiling
3
3
AIR-2026-001077
11.3
52.8
19.9
41.0
Low
Repair
8
Soiling
3
5
AIR-2026-001077
6.4
47.0
20.4
41.9
Low
Repair
9
Soiling
3
6
AIR-2026-001077
7.0
47.6
19.6
40.3
Low
Repair
10
Bypass diode
3
7
AIR-2026-001077
6.4
47.0
20.9
43.1
High
Monitoring
11
Soiling
3
7
AIR-2026-001077
6.4
47.0
20.9
43.1
Low
Repair
12
Soiling
3
8
AIR-2026-001077
6.3
47.5
22.6
43.1
Low
Repair
13
Soiling
1
5
AIR-2026-001078
11.4
51.7
22.5
42.3
Low
Repair
14
Soiling
1
6
AIR-2026-001078
5.2
45.6
17.1
43.0
Low
Repair
15
Cell overheating
1
7
AIR-2026-001078
6.9
47.4
20.0
42.5
Medium
Monitoring
16
Soiling
1
7
AIR-2026-001078
6.9
47.4
20.0
42.5
Low
Repair
17
Soiling
1
8
AIR-2026-001078
3.7
44.0
19.8
39.3
Low
Repair
18
Bypass diode
2
4
AIR-2026-001078
6.4
46.8
12.2
40.6
High
Monitoring
19
Soiling
3
3
AIR-2026-001078
5.1
45.6
19.0
42.1
Low
Repair
20
Soiling
3
4
AIR-2026-001078
5.2
46.0
15.2
38.7
Low
Repair
Aerial thermographic measurement and data processing
For this report, an aerial thermographic inspection methodology was used. Unmanned aerial vehicles (drones) captured infrared thermal and color images of the photovoltaic modules. The assessment was carried out in accordance with the requirements of IEC TS 62446-3. The methodology enables the detection of thermal anomalies, diagnosis of system faults and precise localization of identified findings.
The flight and image acquisition process was optimized so that the data could be collected within a short period and under homogeneous weather conditions, particularly stable solar irradiance. This reduced the influence of changing conditions and enabled a consistent analysis of individual modules.
The analysis was supported by high-spatial-resolution imagery, allowing anomalies to be identified at string, module and individual photovoltaic cell level.
To ensure accuracy, the infrared and color data were compared with each other and manually checked.
Analyzed anomalies
Cell: A localized thermal anomaly affecting a single photovoltaic cell, which may indicate damage, a manufacturing defect or progressive degradation.
Cell Multi: Multiple thermal anomalies affecting cells within one module, which may indicate more extensive damage or degradation of the panel.
Reverse Polarity: A regular checkerboard pattern of alternating warmer and cooler cells, typically associated with incorrect electrical wiring or reversed polarity and potentially reducing module output.
Internal Short Circuit: An extended thermal anomaly associated with a possible internal short circuit in a module or one of its sections, which may cause continuous area heating and reduced output.
Diode: An anomaly affecting one section of a module and associated with the activation or failure of a bypass diode, potentially reducing the panel output by approximately one third.
Diode Multi: An anomaly affecting multiple sections of a module and associated with the activation or failure of multiple bypass diodes, potentially causing a significant reduction in panel output.
Module: A thermal anomaly affecting the entire photovoltaic module, which may be associated with disconnection, an electrical fault or overall degradation.
String: An anomaly affecting a group of interconnected modules, which may indicate a fault reducing the output of the entire string.
Combiner: An anomaly associated with the common connection of multiple strings, which may indicate a fault in the combiner, protection devices, cabling or electrical connections.
Cracking: Cracking or other mechanical damage to a module, which may lead to localized overheating, reduced output and increased safety risk.
Shading: Shading of a panel by a nearby object, obstruction or vegetation, which limits incoming solar irradiance and reduces energy production.
Soiling: Contamination of the panel surface by dust, bird droppings or other deposits, which may cause uneven heating and reduced output.
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