Application notes

Plan a solar-panel drone inspection that produces actionable findings

For inspection contractors and solar asset managers: agree the deliverable, check acquisition conditions and turn thermal observations into a traceable maintenance list.

The key point

The client needs to find the affected module and decide what to investigate. Agree a sample finding record before flying: asset location, thermal original, visible reference, conditions and a clear follow-up action.

Agree what the client will receive before planning the flight

A solar asset manager buying an inspection needs more than a folder of colourful images. Clarify whether the assignment is broad screening, investigation of known underperformance, temperature-based analysis or a repeat survey after maintenance. Each result needs a different level of capture and reporting.

Ask the client to approve one sample finding record before surveying the site. This prevents a common failure: collecting attractive imagery that cannot be mapped back to a row or opened in the client’s software.

Deliverables to agree in the scope
DeliverableMinimum useful contentsAcceptance check
Coverage recordSurveyed areas, omitted areas and the reason for each omissionClient can distinguish inspected from uninspected assets
Finding registerUnique identifier, asset location, image links and observed patternMaintenance team can locate the module
Evidence bundleOriginal thermal capture, visible reference and acquisition conditionsAnalyst can review the basis for the finding
Follow-up listRecommended verification, responsible team and statusEach finding has a next action without inventing a diagnosis

Check operating conditions before collecting the full site

Solar thermal inspection depends on the asset’s operating state and the conditions during capture. Record irradiance when required by the inspection method, cloud changes, wind, ambient conditions, recent rain and whether the relevant section is operating. A disconnected or shaded section can produce a different pattern from a comparable section under load.

Agree the applicable inspection method and its acceptance limits with the client and qualified analyst. Do not copy one flight altitude, irradiance threshold or time of day into every contract. The right limits depend on the method, target, optics and intended conclusion.

Make an early sample pass, review image sharpness and target detail, and confirm the required files are recorded. If conditions change enough to undermine comparison, mark the affected captures for review or recapture before treating them as equivalent.

Choose capture geometry from the defect you need to see

A module-level screening image and a cell-level investigation need different detail. Calculate approximate target pixels using the lens, distance and target size, then validate that estimate on actual imagery. A fast, high survey route may cover the site while leaving the smallest relevant feature unresolved.

Plan viewing angle and visible references so the analyst can distinguish a repeatable panel pattern from reflection or shadow. Flight permissions, separation distances and site restrictions also constrain the available geometry. Record coverage gaps rather than presenting an incomplete pass as a complete inspection.

Turn an observation into a finding, then a verification task

Start with what the image supports. “Localised warmer region on the module” is an observation. “Failed bypass diode” is a proposed explanation that requires appropriate evidence. Keep those fields separate so the maintenance team understands what still needs checking.

Interpretation prompts, not automatic diagnoses
Observed patternContext to inspectUseful next action
One localised warm regionVisible damage, debris, shading and repeatabilityIdentify the module and request targeted inspection
A whole module or group differsOperating state, array layout and comparable neighbouring modulesCheck the asset record and refer for electrical verification
Pattern changes with viewpointReflection, viewing angle and scene geometryCapture a comparison view and retain the context
A later image looks coolerLoad, weather, palette range and measurement settingsCheck comparability before claiming improvement

Use a record the maintenance team can work with

A simple finding template is often more useful than a long narrative. Include: finding ID; site/block/row/module; capture time and time zone; thermal filename; visible filename; operating conditions; camera and lens; observation; proposed follow-up; owner; status. If coordinates are required, verify that their accuracy and export satisfy the client’s locating workflow.

For temperature analysis, retain the supported measurement settings and original radiometric file. A screenshot alone may document the display without allowing reanalysis. Open a sample in the client’s chosen software before the main survey.

Use published cases for workflow ideas, then validate your own job

DJI’s January 2021 account of Drone Visual describes paired visual and thermal capture followed by analysis and reporting. The useful workflow is the connection between acquisition, a locatable anomaly and a follow-up team. Its reported productivity and aircraft setup belong to that specific project; use your own pilot survey to estimate site throughput.

Before choosing a payload, send the intended target scale, working geometry, required files and reporting software with the inquiry. A camera that passes a live-view demonstration may still fail the deliverable the inspection contract requires.

Sources & further reading

Match the payload to your requirements.

Compare documented specifications, then confirm the details of your integration.

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