Are many defects overlooked in solar panel inspections? Instantly identify issues with high-precision AR

On solar power sites, it is not uncommon for small defects to be overlooked during daily solar panel inspections. For example, there are many points to watch for, such as superficial defects like minute cracks or dirt on panel surfaces, slight misalignments in the installed position of mounting racks or panels, newly occurring shading from nearby trees or buildings, and even loosened or damaged wiring or cable interference with racks. However, at solar power plants where thousands of panels are spread across vast sites, it is difficult to perfectly inspect all of these visually with limited time and personnel. In busy field conditions, inspection items tend to become dependent on individual inspectors, and less experienced personnel are prone to inevitably overlook things.

Accumulation of small overlooked defects, however, can lead to reduced generation efficiency or increased risk of serious accidents. For example, missing a loose or poorly connected connector increases the risk of overheating and fire, and failing to notice partial shading or soiling of panels can lead to module degradation or output loss due to hot spots. Improving inspection accuracy for solar panels and reducing such oversights is essential for the safe and stable operation of power plants. One promising solution is a new inspection method that utilizes high-precision AR (augmented reality) technology. With AR capable of high-precision alignment, field teams can detect fine defects that were previously difficult to find and perform inspections quickly. This article explains in detail how AR technology can transform solar panel inspections, specific use cases, and how to introduce it on site.

How high-precision AR changes inspection accuracy and speed

The recently developed AR (Augmented Reality) technology overlays digital information such as CG models and text onto real-world images captured by a smartphone or tablet camera. Applying AR to inspection work allows you to “overlay virtual blueprints onto the site and view them”. For example, projecting a solar panel layout or mounting structure design model onto the site via AR displays virtual guidelines and models over the actual equipment. With high-precision AR combined with high-accuracy positioning technologies (such as RTK-GNSS), smartphone GPS errors of several meters can be reduced to several centimeters, so virtual models and the real equipment remain almost perfectly aligned even if you move slightly. Because you can constantly and precisely overlay the blueprint and the actual equipment on the screen, installation deviations measured in millimeters or slight tilts of components that were previously hard to detect can be identified at a glance.

AR-based real-time comparison dramatically improves inspection accuracy and speed. Inspections that previously relied on veteran intuition and manual work can, with AR, be intuitively understood by anyone on the screen. For example, checking the position of racks or panels used to require multiple people using tape measures and levels; now, simply holding up a tablet lets you instantly check deviations from the design positions. Even non-expert technicians can follow the guides displayed in AR, enabling standardized inspections that do not depend on individual judgment. Because AR presents information visually, it is easy to understand and helps prevent inspection omissions. You can virtually mark or number panels or areas to be inspected, and mark inspected locations as checked, enabling thorough patrols even over wide sites. As a result, you can significantly reduce inspection time, achieve fewer human errors, and improve operational efficiency.

Additionally, high-precision AR makes it easy to record and share discovered defects on the spot. Traditionally, inspectors took photos during inspections, wrote locations and conditions in a notebook, and later matched photos to notes when creating reports. With AR apps, tapping the relevant spot and entering a note automatically saves a photo with location information. For example, if you find a microscopic crack on a panel, you can place a virtual pin or note on that panel in AR and take a screenshot to digitally save “when, where, and what kind of defect was found” instantly. Such digital records directly streamline reporting tasks described later. In this way, high-precision AR revolutionizes solar panel inspections in both precision and speed, greatly contributing to on-site DX (digital transformation).

Integrating AR into on-site inspection workflows

Incorporating high-precision AR into solar power inspection workflows introduces new procedures for on-site verification. Here we explain a concrete inspection flow using AR technology and the main features involved, such as AR display for comparison with design drawings, as-built verification using point cloud data, and digital photo records.

1\. AR-based comparison with design data: Before inspection, import the site layout and design information for the solar power facility into the corresponding AR app. On site, simply pointing a smartphone or tablet camera at the equipment will display the design panel layout and rack positions as virtual models overlaid on the real space. This visualizes subtle deviations that are hard to notice with the naked eye. For example, if a single panel in a row is angled differently or installed outside the alignment line, it will appear to protrude from the virtual panel row on AR, making it obvious. You can also compare the rack’s horizontal and vertical inclination against virtual reference lines. Because installation can be compared in real time to the design, AR helps quickly detect changes such as “a rack has loosened and tilted over time” or “positions have dropped due to ground settlement,” both during final inspections of new construction and during routine checks. AR-based design comparison serves as an as-built (出来形) inspection, greatly simplifying verification of construction quality and alignment standards for after-inspection.

2\. Grasping current conditions via point cloud scans: Many AR devices offer not only overlay displays but also 3D scanning (point cloud acquisition) functions. Recent smartphones and tablets equipped with LiDAR can scan site structures to record current conditions as a dense collection of points (point cloud data). Combined with high-precision positioning, you can assign absolute coordinates (latitude, longitude, elevation) to the acquired point clouds, allowing accurate overlay with maps or CAD design data. Using point cloud data, you can quantitatively capture three-dimensional differences and shape distortions that are difficult to judge visually. For example, panel surface sagging or subtle height differences in racks can be numerically evaluated by comparing point cloud models. Previously, 3D as-built verification required specialized methods such as laser scanners or drone photogrammetry, but AR inspections that let you scan while walking with a smartphone enable one-person 3D recording easily. Acquired point clouds can be sent to the office via the cloud for detailed post-analysis or overlaid on 3D design models for verification. Incorporating this as-built data acquisition and verification into routine inspections dramatically improves early detection of construction defects and long-term degradation monitoring.

3\. Photo records and automatic tagging: AR transforms photo capture and record management during inspections. Normally, inspectors photograph defects, note the photo number, location, and details in a notebook, and later reconcile them to compile reports—a cumbersome and error-prone task. AR inspections automatically tag photos with location and timestamp, eliminating the need to manually record where each photo was taken. For instance, when you take a panel photo in an AR app, the image is linked to coordinates and the date/time, and automatically sorted into the corresponding cloud folder by panel ID. Inspectors can add voice or text notes to photos, creating integrated digital records of images and comments. It’s also possible to include virtual objects (panel numbers or equipment names) in photos so the device in the image is instantly identifiable. For example, showing a virtual sign at the start of a panel row makes it easy to identify the photo location just by viewing the sign in the image. Automated photo organization shortens post-inspection reporting time and allows end-to-end confirmation and recording within the AR app.

4\. AR navigation and checklists: In large-scale solar plants, efficiently touring inspection points is important. Some AR apps include navigation features that display direction and distance to pre-registered inspection routes or points as arrows or lines on the screen. Even across wide sites, guides like “next inspection area: northeast 50 m (164.0 ft)” help ensure complete coverage without getting lost. You can also display parts lists from equipment ledgers as AR checklists and tick items off on the spot as they are inspected. This helps prevent missed inspections and supports reliable rounds. Compared with traditional reliance on paper drawings and handwritten notes, AR significantly improves planning and completeness of on-site inspection workflows.

By integrating AR into inspection flows as described, daily inspections can incorporate advanced functions such as “on-site verification against design data,” “3D scanning for current-condition capture,” “automatic photo and memo recording,” and “navigation with checklist management.” Although these may seem challenging at first, they are achievable through intuitive smartphone or tablet operations, allowing field staff to use them without specialized expertise. The next section examines how the digital inspection data acquired and stored in this way can be used in maintenance and reporting.

Using AR in post-construction maintenance and inspection reporting

In O&M (Operation & Maintenance) of solar power facilities, data collected via AR can be useful in many ways. DX tools offer benefits such as data comparison in routine inspections, streamlined report generation, information sharing among stakeholders, and long-term traceable records.

First, data comparison and tracking of changes over time in routine inspections. When AR and point cloud scans accumulate digital records of equipment conditions at each inspection, you can objectively evaluate deterioration or progression of anomalies by comparing with past data. For instance, overlaying last year’s point cloud model with this year’s allows you to check whether panel tilt angles have changed or whether rack settlement or distortion has progressed. For environmental changes, comparing initial as-built shadow recordings from the final inspection with the latest conditions lets you check whether “trees have grown and created new shadows” or “nearby new buildings are causing shading.” Because you can accurately compare past and present on digital data without relying on human memory or paper records, you can detect changes and take countermeasures. It’s also easy to manage defect histories; you can trace whether a panel that previously had a crack has worsened, or whether a repaired connection has loosened again, by referring to past markers or photos left in AR. Visualizing such histories aids preventive maintenance and timing decisions for part replacement.

Next, automatic generation and sharing of inspection reports. If inspection data is stored in the cloud, it can be used to auto-populate reports such as daily or monthly summaries. For example, using templates in an inspection app, you can generate a report from captured photos and inspection results with a single button. Basic info like date, weather, and inspector name is auto-filled, and photos with comments are organized into the prescribed format, so the inspector only needs minimal formatting to complete the report. This greatly reduces reporting workload and helps prevent human errors (omissions or misentries). Centralized cloud management also facilitates information sharing among stakeholders. Point cloud models or inspection results uploaded from the field can be immediately viewed by office staff or remote personnel. For example, when a field inspector uploads a defect photo to the cloud, headquarters engineers can review it in real time and provide additional instructions or advice as remote support. Having inspection data always up to date prevents using outdated drawings or versions by mistake. Moreover, storing the complete digital history from construction through operation provides reliable records for future asset sales or major replacements. These records allow objective explanations to third parties and can be beneficial for asset valuation.

Thus, information obtained via AR goes beyond mere field checks and directly contributes to streamlining and advancing overall maintenance operations. Improved inspection accuracy enables early detection and remediation of generation losses, preserving revenue from power sales, while faster anomaly detection and richer records enhance safety. Centralized data management and sharing also reduce reliance on individual experience in O&M tasks and allow organizational knowledge accumulation. In the DX era of equipment maintenance, “making full use of field data” is becoming a competitive advantage, and AR inspections are one of the key technologies enabling that.

Conclusion: The future brought by inspection DX and the case for adopting high-precision AR

Solar panel inspection methods are undergoing major evolution through the introduction of digital technologies. While various new approaches such as drone aerial inspections and AI image analysis for anomaly detection are emerging, high-precision AR technology, which can be used directly in the field, has particular potential to fundamentally change how inspections are conducted. With high-precision AR, a single operator can efficiently tour a large solar site, perform accurate checks without mistakes, and instantly record and share data. This offers a powerful solution to industry challenges such as labor shortages and the decline of veteran technicians. Ease of use is also critical for field DX tools, and AR systems that run on familiar devices like smartphones and tablets facilitate smooth adoption among site staff. Intuitive screen operations reduce resistance across all experience levels, lowering training costs.

The barriers to adopting high-precision AR have fallen sharply; now, with a compact RTK-GNSS receiver and a smartphone, AR inspections at centimeter accuracy are achievable. For example, solutions like LRTK, which combine a thin positioning unit that attaches to a smartphone with a dedicated app, make high-precision positioning and 3D scanning—previously requiring specialized surveying equipment—easy with pocket-sized devices. Because positioning, AR display, point cloud capture, and cloud sharing can be completed on a single device, sites new to digital inspections can start using them without difficulty. The important thing is to take the first step toward DX, even if only partially. For example, try AR for panel layout checks during routine inspections, or acquire point cloud baseline data at final construction and expand use gradually as you experience the benefits.

Inspection DX at solar power sites brings broad advantages beyond improved plant uptime and cost reductions: it reduces burdens on field workers and enhances safety. Leveraging high-precision AR technology is a powerful means to realize these benefits. As digital technologies become increasingly sophisticated, solar panel inspections will transform into “no-overlook,” “efficient, and smart” operations. Take this opportunity to explore next-generation inspection methods that incorporate the latest technologies. By adopting high-precision AR for solar panel inspections, you too can experience immediate defect identification and a dramatic improvement in inspection efficiency at your site.