Solar Construction DX Frontline: Solving Labor Shortages with Smartphone RTK and AR

Amid a continuing construction boom for solar power installations, on-site labor shortages have become a major challenge. At large-scale solar construction sites, which involve installing countless solar panels over vast land, a wide range of tasks arise including surveying, stake placement, and equipment installation checks. Traditionally, these tasks were handled by teams including experienced technicians, but recent shortages of younger workers and the aging of skilled technicians have made it difficult to maintain conventional methods. To complete projects with limited personnel, new approaches that dramatically boost productivity are indispensable.

One promising trump card is the promotion of DX (digital transformation) in construction sites. In particular, the “smartphone construction DX” that combines smartphones with cutting-edge technologies is enabling environments where even a single person can perform precise work efficiently across widespread solar construction sites. This article explains the concrete effects and key points of innovations that smartphone-based RTK surveying and AR technology bring to the field. We introduce the frontline of solar construction DX that resolves labor shortages while achieving both improved construction accuracy and reduced work errors.

Labor shortages and challenges faced by solar construction sites

Buoyed by favorable winds for renewable energy, solar power plant construction projects are increasing across Japan. Large-scale solar construction requires extensive workflows—surveying, earthworks, pile driving, racking assembly, and wiring—for installing thousands of panels. Many sites are located in rural or mountainous areas, exacerbating the problem of insufficient skilled workers and the heavy burden of working in harsh environments. Measuring numerous survey points and accurately laying out positions over wide sites normally requires many people, but when staffing is difficult, individual workloads increase and risks such as extended schedules and quality degradation rise.

Conventional analog-centered construction management methods also worsen the labor shortage issue. For example, surveying traditionally used dedicated instruments such as total stations, requiring teams of a surveyor and assistants to spend several days measuring the site. Marking pile positions often relied on paper drawings and tape measures, with crews driving wooden stakes one by one based on experience and intuition. These methods are prone to human error, measurement mistakes, and marking offsets, causing assembly defects and rework in later stages. There are limits to managing expansive sites with few people, and a fundamental reassessment of traditional methods is required.

DX opens the path to labor-saving

A promising solution to these issues is DX (digital transformation) in the construction industry. DX is not merely digitizing tasks but aims to transform business processes themselves through data and IT. In solar construction, DX initiatives accelerating include achieving both labor savings/efficiency and higher work accuracy.

As exemplified by the Ministry of Land, Infrastructure, Transport and Tourism’s *i-Construction* initiative, nationwide promotion of ICT technologies on construction sites is encouraged, and practices such as 3D surveying, remote supervision, and real-time information sharing are spreading. Solar power plant construction is no exception; it must shift away from manpower-heavy methods and secure efficiency and quality through digital tool-based visualization and automation. DX not only supplements labor shortages but also contributes to improved site safety and workstyle reforms, making its importance grow even further.

Smartphone RTK surveying: high-precision positioning that one person can do

One concrete DX solution is smartphone RTK surveying. RTK (Real Time Kinematic) is a technology that dramatically improves positioning accuracy by correcting satellite positioning errors like GPS in real time. While a smartphone’s GPS alone usually has errors of several meters, RTK can reduce that to within a few centimeters. Recently, compact RTK-GNSS receivers that connect to smartphones have emerged, turning a handheld smartphone into a high-precision surveying instrument.

Previously, survey work required carrying heavy tripods and expensive equipment, with a surveyor and an assistant working as a pair to lay out positions. With smartphone RTK surveying, a single operator can walk the site and capture point coordinates one after another. By tapping a button in a surveying app, latitude, longitude, and elevation for a specified point can be recorded instantly, and that data is automatically saved to the cloud. There is no need to take handwritten notes in a field notebook or manually enter data back at the office. From measuring control points to confirming coordinates for each stake, tasks can be completed by one person, greatly shortening what used to take several days. If on a large site each field staff carries a smartphone surveying device and works in parallel, finishing topographic surveys and pre-stake confirmations several times faster than before becomes achievable.

Smartphone app interfaces are intuitive and easy to understand, so even less experienced junior staff can use them readily. The lower barrier compared to learning complex surveying instruments means the intuitive smartphone operation raises overall on-site capability. Digital records also resolve the problem of surveying skills becoming personalized (reliance on specific veterans), allowing the team to share data and ensure quality. Smartphone RTK enables accurate and efficient surveying by a single person, making it a powerful ally for sites suffering from labor shortages.

Improving construction accuracy and reducing mistakes with AR technology

Another revolutionary tool in on-site DX is AR (augmented reality) technology. AR, which overlays design data on real-world views through a smartphone or tablet camera, is highly effective for construction accuracy control. For example, projecting a solar panel layout or racking installation positions onto the actual site with AR makes virtual panel rows and stake positions visible on bare ground. Combined with high-precision positioning, AR can maintain alignment without drift even after walking several meters, allowing designers and workers to always verify the spatial relationship between plans and the site.

This real-time comparison helps prevent construction mistakes. By holding up a smartphone during foundation work and displaying virtual piles on the ground, you can instantly check whether the installed piles match the design. Tasks that used to rely on tape measures and levels for manual checking can be intuitively understood on-screen with AR, reducing human error. When clients or designers inspect the site, displaying a 3D model of the completed installation on the smartphone screen helps everyone share the finished image, preventing misunderstandings from spatial perception gaps and smoothing consensus building.

AR also strongly supports solo stake-layout work. Using navigation functions on the smartphone, the system guides direction and distance to coordinates specified in design drawings. As you approach the target point, a virtual marker indicating “place the stake here” appears on the camera view. Simply following this guidance allows a single worker to install stakes at highly accurate positions even on wide sites. Because AR can maintain accuracy without intermediate marking steps, it contributes to major labor savings and near-zero error construction.

Progress management and quality assurance using point cloud data

The combination of smartphones, RTK, and AR has made using point cloud data (3D scan data) on-site easier. Point clouds are collections of countless points obtained by LiDAR or photogrammetry that represent terrain and structures in three dimensions. Historically, 3D as-built surveying required specialized methods like laser scanners or drone aerial photogrammetry, but modern smartphones with LiDAR sensors, combined with RTK position correction, now allow anyone to easily 3D-scan a site. Walking the site with a smartphone in hand can record ground undulations and placed fill volumes with accurate coordinates.

High-precision point cloud data is powerful for construction progress management and quality checks. For example, if you scan and save the original ground before earthworks, you can compare it to periodic subsequent scans to quantify where and how much soil has been added or removed. Soil volume management that once required surveyors to measure heights point-by-point and calculate volumes can now be done instantly by computing differences between point clouds. Overlaying the planned terrain data (design model) with the actual point cloud makes shortages/excesses in fill and shape deviations obvious at a glance, helping detect discrepancies early and preventing rework.

Point clouds are also effective for overseeing expansive solar farms. Subtle terrain changes that are hard to visually inspect can be compared in detail with 3D data. Progress tracking that once required walking every corner of a site can be visualized digitally when converted to point clouds, making it easy to spot delays and defect areas. Such data-driven quality control enables a small team to thoroughly check a wide site and maintain quality.

Direct connection between site and office via cloud sharing

A key strength of smartphone DX is that all collected data can be shared instantly via the cloud. Previously, photos and survey data captured on-site had to be transferred by USB or email or compiled into paper documents back at the office, which was time-consuming. With DX tools, photos and records captured on a smartphone are uploaded to the cloud and can be viewed in real time from remote locations.

For example, photos taken with a smartphone app are automatically tagged with date, time, and coordinates, making it easy to organize “when and where a photo was taken.” There is no need to create folders and paste photos into drawings; you can quickly find the information you need. It’s also possible to auto-generate daily and weekly reports from on-site data. By fitting survey results and inspection records into cloud-based templates, reports are completed and the workload on staff is greatly reduced.

Centralized cloud management of data also strengthens team collaboration. Point cloud models and photos uploaded from the field can be immediately reviewed by office engineers or clients, who can send feedback—enabling smooth remote support. Because the latest information is always shared, mistakes like using outdated drawings are avoided. Moreover, construction history data is retained in the cloud after completion, so records can be referenced quickly during inspection and maintenance, allowing DX benefits to be realized across the facility’s entire lifecycle.

Intuitive smartphone operation is friendly to both young staff and the field

The keys to embedding DX tools on-site are intuitive operability and usability. Smartphone-centered solutions are easy for on-site workers to accept because they run on devices people are already familiar with. Not only younger staff but even veterans less accustomed to smartphones can start using them without resistance thanks to intuitive UIs and clear operation flows. Compared to complex specialized equipment, DX tools that can be handled with a “smartphone feel” reduce training costs while raising everyone’s skills.

The psychological effects of smartphone DX on the site should not be overlooked. Using the latest technologies makes site work smarter, and coupled with reduced physical burden and improved safety, it leads to improved workplace conditions. When previously cumbersome surveying and recording tasks become simple, site supervisors and construction managers can focus on higher-value work, and the site becomes more appealing to young talent as a “cool” technical workplace, aiding recruitment. If a culture of staff using data takes root through DX, organizations can maintain high-quality construction without relying on personalized craftsman skills.

Effects and outlook of solar construction DX

Smartphone RTK and AR-based solar construction DX deliver significant effects directly linked to solving labor shortages. Increasing the amount of work a single person can handle allows projects to proceed with limited personnel. As a result, schedules shorten and costs fall, bringing business advantages. Also, by improving construction accuracy and reducing work errors, workmanship quality stabilizes and rework or complaints are prevented. Because solar power plants are infrastructure with many panels and equipment operating over long periods, initial construction quality management affects long-term power generation efficiency and maintenance costs. High-precision construction enabled by DX is therefore important from the standpoint of long-term quality assurance.

In the future, further on-site DX evolution is expected—including integration with AR glasses and autonomous construction machinery—not limited to smartphones. But the foundation is first to diffuse tools that “anyone can use on a smartphone” at job sites. The DX know-how cultivated on the frontline of solar construction will likely spread to other civil engineering and building sites. Efforts to address the structural challenge of labor shortages with digital technology in solar construction DX offer one example of shaping the future of Japan’s construction industry.

Realizing smartphone DX solutions with LRTK

A solution that powerfully supports such smartphone-based on-site DX is LRTK. LRTK (pronounced “L-R-T-K”) is a site DX platform using smartphones that combines high-precision GNSS devices, a dedicated app, and cloud services to provide the functions needed for construction management in an all-in-one package. Specifically, a single smartphone enables the following features:

• Centimeter-level positioning and 3D scanning: A small RTK-GNSS receiver attached to the smartphone allows you to always know your position with centimeter accuracy. Combined with the smartphone’s built-in LiDAR, you can obtain point cloud data with absolute coordinates with one tap. Topographic surveys and fill volume measurements on vast sites can be performed immediately on-site.

• Design verification and navigation with AR: Design drawings and 3D models can be displayed as AR on the smartphone screen and overlaid on the real scene. LRTK’s high-precision positioning keeps displays accurate and stable, allowing inspections by overlaying virtual models on structures under construction and guiding stake points with AR markers so these tasks can be done solo.

• Automatic organization of photos and records: Photos taken with the LRTK app are automatically tagged with position coordinates and timestamps, and are linked on the cloud with maps and point cloud data for chronological management. You can also perform AR comparisons with previously taken photos at the same location for monitoring and reporting.

• Cloud sharing and team collaboration: All data collected with LRTK syncs to the cloud instantly and can be viewed and measured from an office PC via a browser. Remote engineers can quickly review point clouds and photos taken on-site and provide advice, enabling real-time collaboration.

By adopting LRTK, the processes of “measuring, verifying, recording, and sharing” required at solar construction sites can be almost entirely completed with a smartphone. Because LRTK implements the DX functions discussed in this article as a single integrated tool, on-site introduction is simple. Even for large-scale solar farm construction, LRTK can be a dependable partner for efficiency and quality improvement. If you are a construction manager struggling with labor shortages, consider leveraging smartphone-centric DX tools like this. LRTK helps update your site with cutting-edge technology so that even small teams can safely and reliably build high-quality solar power plants.