No functional abnormality
Module operates within expected thermal thresholds. Monitored during the next annual pass.
IEC TS 62446-3 compliant inspection · Level 2 certified thermographer
Solar farm drone thermography: pinpoint every cell anomaly before it turns into an outage
We fly your PV plant with high-resolution radiometric thermal cameras and examine every module image-by-image. You receive a standard-compliant engineering report, an interactive browser viewer, and CSV data with all anomalies classified by severity.
Quotation within 24 hours · The solar plant continues generating during flight
- Official SolarCleano and Chemitek distributor
- ISO 14001 certified
- Registered contractor (REA)
- Over 30 years of industrial engineering experience
- Technical response in under 24 hours
Licensed UAS commercial operator certified for open and specific categories (standard STS-01 and STS-02 scenarios) with comprehensive civil liability coverage.
Hotspots in photovoltaic modules
What a drone thermographic inspection reveals
We structure findings into three actionable categories according to recommended intervention and Class of Abnormality (CoA).
Thermography pinpoints thermal signatures and quantitative severity. For balance-of-system electrical anomalies, the root cause is validated on-site by field technicians.
Resolved by cleaning or removing the root cause
Confirmed via visual RGB comparison.
- Soiling & DustCoA 1–2
Hotspots, typically along the lower edge of the module. Clean
- Bird DroppingsCoA 1–2
Localized hotspots directly over visible deposits. Clean
- Cemented SoilingCoA 2
Industrial fallout, scale, or lichen not removed by rain. Specialized washing
Térmica
Visible- Vegetation OvergrowthCoA 1–2
Overheating matching weed shading profiles. Vegetation control
- ShadingCoA 1–2
From structural elements, adjacent rows, wires, or temporary scaffolding. Monitoring
- Perched Birds or DebrisCoA 1
Present on module during the flight pass. Logged in report
Potential internal module defect
No external visible cause detected.
- Single Cell HotspotCoA 2–3
Caused by micro-cracks, internal manufacturing defects, or lower-yield cell. Confirmed by electroluminescence.
- Snail TrailsCoA 2
Typically indicative of cell micro-cracking and moisture ingress.
- DelaminationCoA 2–3
Layer separation, bubbling, or backsheet degradation.
Térmica
Visible- Shattered Front GlassCoA 3
Always classified as CoA 3 due to electrical and fire hazards.
- Cell InterconnectsCoA 2–3
Linear thermal anomaly from bad solder joints, ribbon fatigue, or corrosion.
Electrical balance & string patterns
Always requires technician verification on-site.
- Uniform Hot Sub-stringCoA 2–3
1/3 or 2/3 of module: activated or damaged bypass diode, ribbon disconnection, or junction box fault.
- Irregular Hot Sub-stringCoA 2–3
Likely short-circuited diode.
- Entire Module Heated (Open Circuit)CoA 2
Blown fuse, disconnected MC4 lead, open isolator, insulation fault, or junction box defect.
- Full Inactivated StringCoA 3
String fuse blown, DC cabling damaged, combiner box failure, or inverter section down.
Matriz
Fila- Overheated Junction BoxCoA 2–3
Significantly hotter than adjacent modules: loose terminal, defective diode, or compromised potting.
- Negative String End HotspotsCoA 2
Gradient thermal anomaly on modules near the negative terminal: potential PID degradation.
- Diffuse Heating & YellowingCoA 1–2
Potential EVA encapsulant browning and thermal dissipation fatigue.
Other complex patterns are catalogued and earmarked for complementary electrical or electroluminescence testing.
Classes of Abnormality
Understanding CoA 1, 2, and 3 classifications
Moderate thermal abnormality
Investigate root cause and execute scheduled corrective maintenance within a reasonable timeframe.
Critical safety & fire hazard
Risk of arc flash or fire hazard. Immediately isolate string and replace affected hardware.
- In simplified inspections, the class is assigned standardly by thermal pattern. Shattered glass is always classified as CoA 3.
- In detailed inspections, the class is adjusted using measured temperature differentials (ΔT).
- External causes resolved by specialized washing do not escalate class even if hot.
- Internal semiconductor defects escalate based on absolute temperature rise.
IEC TS 62446-3 Inspection Standard
Simplified vs Detailed Inspection: same flight pass, deeper diagnostic depth
| Included deliverables | Simplified | Detailed |
|---|---|---|
| Anomaly mapping on plant CAD/orthomosaic | Yes | Yes |
| Radiometric review over original thermal capture | Yes | Yes |
| Thermal and RGB image crops referencing source files | Yes | Yes |
| CoA classification | By anomaly pattern | Calibrated to measured temperature |
| Normalized ΔT temperature rise at 1,000 W/m² | — | Yes |
| Documented parameters: emissivity, distance, humidity | — | Yes |
| Full raw radiometric dataset attached | — | Yes |
| Primary operational use | General plant condition & O&M planning | Manufacturer warranty claims & M&A due diligence |
Simplified
- Anomaly mapping on plant CAD/orthomosaicYes
- Radiometric review over original thermal captureYes
- Thermal and RGB image crops referencing source filesYes
- CoA classificationBy anomaly pattern
- Normalized ΔT temperature rise at 1,000 W/m²—
- Documented parameters: emissivity, distance, humidity—
- Full raw radiometric dataset attached—
- Primary operational useGeneral plant condition & O&M planning
Detailed
- Anomaly mapping on plant CAD/orthomosaicYes
- Radiometric review over original thermal captureYes
- Thermal and RGB image crops referencing source filesYes
- CoA classificationCalibrated to measured temperature
- Normalized ΔT temperature rise at 1,000 W/m²Yes
- Documented parameters: emissivity, distance, humidityYes
- Full raw radiometric dataset attachedYes
- Primary operational useManufacturer warranty claims & M&A due diligence
Because raw airborne data is identical, a simplified inspection can be upgraded to detailed later for targeted strings without mobilizing crews again.
Tier 1 manufacturers reject uncalibrated drone surveys. The detailed tier provides exact radiometric readings under standard test conditions, forming an ironclad warranty claim.
Deliverables
Three deliverables: audit report, interactive web visor, and structured data
IEC TS 62446-3 Engineering Report
Signed by a certified Level 2 thermographer with comprehensive statistical charts by inverter, block, and string.
Interactive Plant Web Visor
A single standalone browser file with zero software installation required. Features an interactive thermal-to-RGB sliding curtain.
Structured CSV Data
Complete anomaly database with coordinates and metadata, formatted for immediate import into your CMMS / GMAO.
Every single anomaly is pinpointed on your plant map; when single-line diagrams are provided, tracking maps down to inverter, combiner, and string. Each entry includes thermal and visible images and recommended corrective action.
Turnaround time is confirmed in each technical proposal based on plant capacity (MW), calculated from image reception.
Download inspection client dossier (PDF)Flight inspection requirements (PDF)
Drone solar thermography
Flight hardware, methodology, and standard weather windows
1 / 6
1 · Share facility data
Module count, capacity (MWp), location, and single-line diagram if available.
2 · Set the weather window
Forecast monitoring to ensure flight conditions meet IEC standards.
3 · Autonomous flight pass
Conducted while the solar asset operates under maximum solar generation.
4 · Analysis & delivery
Level 2 thermographer analysis, interactive web visor, and CSV delivery.
Professional equipment
DJI Matrice 4T equipped with 640×512 radiometric thermal sensor and high-resolution RGB camera. Ground resolution around 2 cm per pixel at flight elevation, exceeding IEC standards.
Engineering methodology
The orthomosaic serves only as a spatial navigation map. Diagnostics are conducted image-by-image on uncompressed radiometric thermograms, signed by a Level 2 certified thermographer.
Standard IEC flight conditions
- Minimum solar irradiance of 600 W/m² on module surface (flight during peak mid-day hours).
- Maximum wind speed of 28 km/h.
- Cloud cover restricted to no more than 2/8 cumulus.
- Solar plant actively generating under sufficient grid load.
- If weather shifts below threshold, flight is rescheduled at no penalty to guarantee legal IEC validity.
Integrated maintenance
Explore maintenance plansFirst clean, then inspect
IEC standards stipulate clean or low-soiled modules for conclusive inspection. Thermography conducted after specialized robotic washing eliminates false positive thermal signatures from bird droppings and dirt.
Target applications
For asset owners, investment funds, O&M contractors, and commercial rooftops
Plant asset owners
Pinpoint underperforming tables and quantifiably assess generation degradation without walking miles of arrays.
O&M contractors
Accurate mapping down to inverter and string level, with ready-to-use CSV records for maintenance teams.
Investment funds & IPPs
Validate technical health during asset transactions with independent reports signed by certified Level 2 personnel.
Commercial & industrial rooftops
Inspect rooftop PV systems without scaffolding, work-at-height hazards, or stepping on modules.
Quality assurance
Why partner with Clean Sunny for drone thermography
Licensed pilots & Level 2 thermographer
Fully compliant airspace authorization with analysis validated by certified professionals.
Zero operational downtime
Conducted during live operations while the facility injects maximum power into the grid.
Complete 3-format deliverable
Executive PDF audit report, browser-based interactive web viewer, and raw CSV dataset.
Multi-MW portfolio capacity
Rapid deployment across commercial portfolios and utility-scale solar farms throughout Iberia.
Return on investment calculator
How much revenue is hidden behind undetected solar anomalies?
Evaluate the financial impact of common thermal cell and string anomalies across your annual production.
Frequently asked questions
Common questions about aerial solar thermography
Does the solar plant need to be shut down?
No. On the contrary: the facility must be fully operational and under active load, as thermal anomalies only manifest when modules are actively conducting current.
What site preparations are required?
Site access and a designated point of contact on inspection day. If available, layout maps and single-line diagrams facilitate string mapping.
What happens if weather conditions deteriorate?
Flight dates are rescheduled at no cancellation penalty. Standard IEC inspections require minimum 600 W/m² irradiance to remain valid.
Can this report be used for manufacturer warranty claims?
Yes. The detailed inspection tier provides radiometric measurements under strict standard conditions, offering the highest empirical credibility for replacement claims.
What is the key difference between simplified and detailed tiers?
The detailed tier measures the calibrated absolute temperature of every hotspot and calculates the normalized temperature delta (ΔT).
What do CoA 1, 2, and 3 classifications mean?
They represent IEC abnormality classes: CoA 1 (minor/monitoring), CoA 2 (moderate defect requiring scheduled repair), and CoA 3 (critical safety/fire hazard requiring immediate isolation).
Do I need special software to open the visor?
No. The interactive plant visor is a standalone HTML document that opens directly in any standard desktop browser.
Do you operate across Portugal as well as Spain?
Yes. We maintain operational crews in Porto, Barcelona, Madrid, and Seville, delivering turnkey coverage across the entire Iberian Peninsula.
Formal quote
Request your drone thermography inspection proposal within 24h
Share your module count and site location. We provide an itemized fixed proposal in less than 24 hours.
- Itemized technical quotation within 24 hours
- Level 2 certified thermographer
- Fleet operations across Spain and Portugal
Phone +34 936 555 555 · WhatsApp +34 623 984 040
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