How owners, EPCs and O&M teams use solar thermography differently, from commissioning scans to warranty claims and repairs, on one platform.
Karthik Mekala
CMO
Published on
A drone thermal inspection of a utility-scale solar plant produces one set of data, and three teams read it differently. The owner wants to know which defects threaten output and what the contractor owes. The EPC wants every defect closed before handover. The O&M team wants the exact module to fix and proof that it was fixed.
When each team works from its own PDF report, findings can go missing between handovers, and disputes follow. Solar thermography, the use of infrared imaging to find potential equipment defects and thermal anomalies in PV installations, works best when the same inspection data serves all three teams. The sections below follow the same scan through the owner's risk review, the EPC's handover and the O&M repair.
Solar thermography, or solar panel thermal imaging, is infrared imaging of PV arrays to find modules, strings and components running hotter than normal. A thermal camera, usually carried by a drone, records surface temperature across the array, and software or an analyst flags the areas that stand out.
The scan itself is standard. What changes by team is the timing, the resolution, the reporting format and the follow-up. An EPC needs a scan before handover, an O&M team needs one on a repeating schedule, and an owner needs results that roll up across plants. A thermography strategy sets which of those each team gets and who acts on the findings.
These are the anomaly types the rest of this article refers to.
Hotspots: cells or modules running hotter than their neighbours.
Bypass diode failures: a failed diode can leave part of a module running hotter than the rest.
String faults: a whole string showing a different temperature from the strings around it.
Open circuits: modules or strings that are not delivering current.
Cracked cells: damaged cells that can heat unevenly.
Soiling: dirt or shading that raises local temperatures.
Tracker faults: rows that are not following the sun as they should.
Aerial thermography of a solar plant uses drone-based scans that cover the full site quickly and produce imagery that can be placed on a map. Handheld infrared cameras give a close-up view of a single component. Many utility-scale programs use aerial scans first and handheld checks to confirm what the aerial scan found. Our guide to drone-based IR analysis covers the workflow in more detail.
An owner is responsible for how the plant performs, for the financial exposure when it does not, for holding contractors to account and for long-term reliability. A scan supports those decisions when its results are connected to operational context and to field-verified findings. On its own, a thermal image is a list of warm spots.
Owners can rank findings by four things: anomaly severity, estimated power loss, the equipment affected and the operating context. A defect that affects a whole string costs more output than one confined to a single module, so the two should not get the same urgency. Treating every detected anomaly as equally urgent spreads repair effort thin and leaves the most consequential issues waiting their turn.
In Therm, each anomaly carries an estimated temperature difference and potential power loss, and the Defects page can be filtered by defect type, status, priority and temperature difference.
Inspection records, asset identifiers, field verification results and remediation history give owners a factual basis for reviewing contractor performance. The same records can support potential warranty claims.
Thermal imagery alone does not establish warranty eligibility. Manufacturers set their own requirements, and supporting inspections may also apply, so the record needs the serial number, the location, field verification and the repair history alongside the scan. Reports that follow a recognized method such as IEC TS 62446-3 are easier to defend, and our guide to solar warranty claims lists what a strong claim needs.
Asset managers who run several plants need to see which anomalies keep recurring, which corrective actions are still open and how each site's inspection turned out. That view works best at the asset level, with findings ranked by risk and not summed into a generic dashboard. Additional information such as module manufacturer, type, batch or serial number helps analysts understand patterns in defect occurrence and can help with module selection and procurement decisions in future projects.
Therm's reports show total defect impact and resolution status, and they highlight recurring issues and critical areas. Therm is built to give owners and asset managers clearer visibility into thermal risk across the portfolio; with the TaskMapper digital twin as its backbone, users can easily correlate defect data against module types, production batches, or manufacturers to get important data.
EPCs use thermal inspections to find potential installation and equipment issues before solar commissioning and handover. For an EPC, what matters is construction quality, who owns each defect, how quickly it is fixed and whether the evidence supports project acceptance.
Scanning each completed construction phase can surface issues before the plant passes to the owner. Early identification gives the EPC a chance to investigate while construction teams and project records are still readily accessible. In most EPC contracts, a pre-commissioning round of thermal scanning followed by remediation of defects is a mandatory requirement.
In a published SenseHawk case study, a leading global EPC scanned each completed phase of a solar and storage project with nearly 2.5 million modules when complete, to keep defect remediation on track with the construction schedule. Therm classified defects by probable cause and severity and mapped them on the site's digital model.
Once an anomaly is mapped to a specific asset, it can become an assigned task with a priority, evidence and a closure status. That lets an EPC coordinate site teams, track unresolved defects and keep thermal findings inside the construction workflow and out of a separate report.
In TaskMapper, tasks can be linked to a defect and carry an assignee, due date and status, and each defect moves through statuses from Pending through Verified and In Progress to Resolved. In the case study above, each defect could be converted into a task for the EPC's field teams to investigate, remediate and update.
For handover, the EPC keeps the inspection results, field verification notes, corrective actions and the relevant asset documentation together. When those records are linked to the assets, the owner and the incoming O&M team can see what was detected, what was resolved and what remains open. SenseHawk's commissioning tools give every asset a Digital Birth Certificate, a record of its as-commissioned state.
Solar O&M teams live with the results. They need to know exactly which module to fix, how urgent it is and how to prove it was fixed. For them, thermography is about speed of action and fewer wasted site visits.
A common schedule is a baseline scan at handover, then an annual or seasonal scan during operations, plus event-driven scans after storms, module cleaning or an unexplained performance dip. The right cadence depends on the site, the equipment and the contract terms. Scan quality also depends on capture conditions, which our guide to drone thermal inspection mistakes covers.
Between scans, severity and power-loss ranking decide which issues get fixed first. In Therm, priority ranks defects by urgency and helps plan field team workload.
Matching a thermal anomaly to a SCADA alarm or an underperforming inverter helps confirm the fault. An anomaly with no matching alarm or output loss is worth checking before a crew is sent, which helps avoid chasing false positives.
Field verification catches the rest. In the SenseHawk case study above, field investigation found that over 60% of the "cell failure" hotspots flagged in the first completed phase were benign, caused by light visible through scribes.
A crew opens the defect in the TaskMapper mobile app and navigates to its exact location on the map. On site, the crew inspects the module, captures photos and notes, and updates the defect status and the linked task. The in-app camera can stamp each photo with the date, time and GPS coordinates, which makes the repair record easier to verify. The app works offline once maps and layers are loaded, and it syncs when the connection returns.
Because the crew arrives knowing the module, the defect type and the notes on file, there is less to re-confirm on site, which reduces the chance of a repeat visit.
Owners and IPPs | EPCs | O&M teams | |
|---|---|---|---|
Primary goal | Protect asset value and output | Hand over a plant with defects closed | Restore performance with fewer wasted visits |
When they scan | Handover baseline and periodic audits | Completed construction phases, before commissioning and handover | Scheduled cycles plus event-driven scans |
What they measure | Severity, estimated power loss, affected equipment | Installation and equipment defects by location and owner | Severity, power loss and temperature difference per module |
Report they need | Risk and remediation status across plants, plus warranty evidence | Defect list with evidence, closure status and handover records | Work list with exact module, urgency and notes |
Success metric | High-priority anomalies resolved; claim-ready records | Defects closed before acceptance | Defects resolved and verified; repeat visits avoided |
The three teams scan at different times and read different parts of the results, but they work from the same asset-linked data. When that data sits in one record, a finding from the EPC's scan is still visible to the owner and the O&M team years later.
Separate PDF reports for each team can cause lost findings and disputes at handover. Therm, SenseHawk's solar inspection software for drone thermal scans, runs inside TaskMapper as one system: owners see risk, EPCs track readiness and O&M executes repairs.
Therm's AI classifies more than 30 anomaly types from drone thermal scans and estimates the temperature difference and potential power loss for each one. Each anomaly is pinned to its module, string and inverter on the plant map, and defects are color-coded on thermal, visual and CAD map layouts.
The EPC's commissioning scan, the owner's audits and the O&M repairs all sit on one record per asset, so each defect has a traceable history from detection to resolution. Status, notes, photos and assignees stay with the defect, and the full history is available to everyone with access.
Each team needs different outputs from the same scan. Owners need ranked risk and evidence they can rely on, EPCs need defects closed with records to show it, and O&M teams need the exact module and a way to prove the repair. Aligning scan standards across the lifecycle, from the commissioning baseline to periodic inspections, keeps those outputs consistent, and a shared platform makes that alignment practical.
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What is solar thermography, and why is it important for solar farms?
Solar thermography is infrared imaging of PV arrays to find modules, strings and components running hotter than normal. It matters on utility-scale plants because thermal anomalies can point to defects that reduce output, and a drone scan covers far more equipment than a walk of the site.
How often should a utility-scale solar plant be scanned with thermography?
There is no single interval. A common schedule is a baseline scan at handover, then an annual or seasonal scan, plus extra scans after storms, module cleaning or an unexplained performance dip. The right cadence depends on the site, the equipment and the O&M or warranty terms.
Who should pay for the commissioning thermal scan, the owner or the EPC?
The EPC contract settles it, so the answer varies. What matters is that the contract states who commissions the scan, which standard it follows, how findings are verified and who fixes them before acceptance.
What defects can drone-based solar thermography detect?
It can reveal hotspots, bypass diode failures, string faults, open circuits, cracked cells, soiling and tracker faults. A thermal scan shows temperature differences, so findings should be verified in the field before repair.
The scan itself is standard. What changes by team is the timing, the resolution, the reporting format and the follow-up.
Karthik Mekala
CMO
