Digitalization from Surveying to As-Built Management: A Field Revolution in Solar Construction

Digital technologies are increasingly permeating processes from surveying to as-built management at solar power construction sites, and on-site operations are beginning to change significantly. Construction projects that install thousands to tens of thousands of solar panels over vast sites involve a wide range of tasks, such as terrain surveying, checking earthworks progress, verifying panel and racking placement, and preparing construction records. Traditionally, many of these tasks were handled manually and on paper, leading to numerous challenges in efficiency and accuracy. Now, digitalization is resolving these issues and driving a "field revolution" that delivers benefits such as reduced manpower, higher accuracy, prevention of work errors, and faster information sharing. This article explains the flow of digitalization from surveying to as-built management at solar construction sites and the effects it brings.

Current Situation and Challenges at Solar Construction Sites

Many processes at solar power plant construction sites still rely on analog management methods. For example, traditional surveying required specialized equipment like total stations and surveying personnel, and the obtained measurements were recorded by hand on paper drawings. Work instructions were often given verbally or via phone or email, and on large sites site supervisors needed to walk the entire area to check progress, placing a heavy burden on them.

Moreover, delays in information sharing between different stages often lead to mistakes and rework. It can take time to confirm whether earthworks have reached the planned elevations, and errors discovered later can necessitate rework. Managing site photos and preparing as-built documentation and reports are also largely manual tasks, creating a substantial burden for site representatives and supervisors. Such person-dependent and inefficient management is becoming unsustainable amid labor shortages and an aging technical workforce, so prompt improvements are needed.

Why Digitalization Is Needed

A key solution being highlighted to fundamentally address these on-site issues is construction DX (digital transformation). Rather than merely digitizing paper, the goal is to use digital technologies to transform business processes themselves and dramatically improve productivity and accuracy. Several factors make DX urgent in solar construction sites:

1. Labor shortages and skill transfer issues: Managing vast sites traditionally requires many people, but the construction industry as a whole faces a shortage of young workers and an aging of skilled personnel. To operate complex sites with limited staff, improving individual productivity is essential. DX-driven labor saving and automation of surveying and management tasks will be critical for future site operations.

2. Demand for shorter construction periods and cost reduction: With growing demand for renewable energy, rapid commissioning of solar plants is required. Efficient project execution is crucial for business, and using digital technologies to shorten surveying and inspection times and to share data instantly is expected to reduce wasted waiting time and rework. DX can deliver significant benefits both in shortening schedules and lowering costs.

3. Nationwide promotion of DX: Policies such as the Ministry of Land, Infrastructure, Transport and Tourism’s "i-Construction" strongly encourage the use of ICT and 3D data in construction. Solar plant sites are no exception; introducing the latest technologies like drone surveying, AR-based visualization, and remote supervision is expected to improve safety and quality.

Easy, High-Accuracy Surveying and Recording with a Smartphone

One concrete tool supporting DX is "smartphone-based site management." Modern smartphones have become highly capable, and some models now include high-precision GNSS units (satellite positioning) or 3D scanners (LiDAR). By attaching a dedicated compact RTK-GNSS receiver to a smartphone, a palm-sized device can become a surveying instrument with centimeter-level accuracy. Whereas survey technicians once needed to operate total stations or large GPS surveying units, now site personnel can record coordinates of needed points instantly by simply pressing a button on a smartphone app. Latitude, longitude, and elevation data are saved automatically, eliminating the need to jot them down on paper.

Using a smartphone’s camera and various sensors also dramatically streamlines site documentation. When you photograph an area of interest, the image file is automatically tagged with the shooting location coordinates and timestamp. There is no need to write notes on paper drawings; all records can be kept as digital data. Because recorded data can be uploaded to the cloud on the spot, there is no longer a need to return to the office to recreate reports.

By centering operations around a single smartphone, a workflow that completes surveying, recording, and sharing on-site is becoming achievable. Because the tools can be operated on familiar devices, they are easy to adopt for both veterans and newcomers, and using a one-device-per-person digital site tool can provide unprecedented mobility and efficiency.

Visualizing Progress and As-Built Conditions with 3D Point Cloud Data

Because earthworks for solar plants often involve large-scale embankment and excavation, accurately understanding the site topography and managing work progress and earth volumes is extremely important. Here, 3D point cloud data is highly effective. Point cloud data are three-dimensional surveying data recorded as a collection of countless points (a point cloud) representing the surrounding environment.

Traditionally, such 3D surveying required specialized methods like terrestrial laser scanners or drone photogrammetry. However, some modern smartphones now include LiDAR sensors, and by combining these with high-precision GNSS positioning, anyone can easily perform a 3D scan of the site. Simply walking the site with a smartphone can capture point cloud data of the terrain and structures, and each point can be assigned geodetic coordinates (latitude, longitude, elevation), allowing scan results to be recorded with accurate positioning information.

Using 3D point cloud data greatly streamlines progress checks and earth volume management. For example, you can scan the terrain before earthworks begin and save the data, then compare it with regular subsequent scans to determine exactly how much soil has been removed or added. Tasks that used to require surveyors to measure heights at multiple points and derive cross-sections to calculate volumes can now be done by digitally computing differences between point clouds, automatically yielding cut-and-fill quantities and saving significant time. Overlaying scanned as-built data with the planned design terrain makes discrepancies in volume and shape immediately apparent.

Point clouds are also powerful for progress management. Subtle topographical changes and the status of work that are hard to see with the naked eye can be compared in detail using 3D data. This enables early detection of areas that are behind schedule or have quality issues, allowing prompt corrective measures. On vast solar farms where comprehensively understanding the entire site was previously difficult, point cloud scanning allows the whole site to be digitally "visualized" as points.

Verifying Design Data Against the Site with AR Technology

AR (augmented reality) technology is another promising solution for site management in solar construction. By holding up a smartphone or tablet, design data can be overlaid on the live camera view of the site, enabling real-time comparison between the planned drawings and actual conditions.

Specifically, overlaying panel layout drawings or 3D models of earthworks in AR lets you visualize the completed equipment that is not yet installed. For example, during foundation work you can display the intended racking positions in AR and check whether marked stake locations match the design. While traditional methods relied on tapes and transits for staking and verification, AR enables intuitive detection of misalignments and helps reduce human error.

AR also helps stakeholders beyond construction personnel. When clients or designers visit the site, they can share a visualization of the completed state through a tablet. Showing, for example, "this is how the panels will be arranged here in the future" as a 3D visual overlaid on the real landscape helps everyone grasp the spatial image.

Moreover, AR is effective for staking in locations that were previously difficult. On steep slopes or restricted-access areas, virtual markers (stakes or lines) can be displayed in AR to allow safe position checks. Resolving gaps between design and execution through AR strongly supports smooth construction without rework.

Automating Site Records and Cloud Sharing

The benefits of digitalization are not limited to technical aspects like surveying and design verification. DX also has major effects on automating and streamlining daily site records and reporting tasks. During the construction of a solar power plant, vast amounts of record-keeping are required, including progress photos, various inspection records, and daily/weekly reports. DX can automate as many of these tasks as possible and create a system for cloud-based sharing.

For example, when a photo is taken with a smartphone app, the image file can automatically be tagged with metadata such as date/time, location, and responsible person. You can organize photos into albums by work area or enter descriptions according to templates to maintain standardized records. Because captured data are uploaded to the cloud in real time, there is no need to copy images to office PCs or send them by email later.

Form generation can also be simplified with DX. Daily and weekly reports and as-built management documents that site supervisors used to create in spreadsheets or on paper can be automatically generated from the digital data collected on-site. For example, simply mapping survey data and photos into a cloud-based template can almost complete a progress/quantity report. Managing information in the cloud also ensures everyone can reference the latest data and prevents mistakes from using outdated drawings or files.

Cloud sharing also bridges sites and remote locations. Managers and clients in distant offices can view site progress data and photos via the internet at any time. This eliminates the waste of printing and carrying large volumes of paper for reporting meetings and speeds up decision-making. Centralized data management also makes it easy to reference construction records during post-handover maintenance and inspections, so DX benefits the entire lifecycle of the solar facility.

Case Study: Effects of DX on the Field

In practice, introducing a smartphone-centric DX tool at a large-scale solar power construction site dramatically changed site management. Tasks such as as-built surveying, which had previously been outsourced to surveying companies and done only about once a week, were performed quickly by site staff daily, enabling constant management based on the latest terrain data. AR-based design verification sharply reduced construction errors and prevented additional rework. Furthermore, photos and records shared in the cloud were accessible in real time by headquarters and partner companies, greatly improving communication among stakeholders.

Reported main effects include:

• Shorter surveying and inspection times: Surveying and inspection work time was reduced to a fraction of what it used to be, contributing to labor cost savings and schedule compression.

• Improved construction quality: Construction checks using AR and point cloud data reduced rework and losses caused by mistakes.

• Faster information sharing: Instant cloud integration of data shortened waiting times for instructions and reports.

• Easier skill transfer: Smartphone-centered tools are intuitive for both veterans and newcomers, making it easier for those unfamiliar with IT to become proficient.

• Safety and environmental improvements: Fewer surveys in hazardous areas and reduced paper usage contributed to safety and environmental benefits.

Thus, promoting on-site DX not only raises productivity and quality but also positively affects working styles and safety. The effects are especially pronounced on large solar plant construction sites.

Solar Construction DX Realized with LRTK

One solution that strongly supports on-site DX is our product, LRTK. LRTK is a smartphone-based site DX platform that, together with a dedicated compact GNSS receiver, a companion app, and cloud services, provides all the functions needed for site management in an all-in-one package. It covers everything from simple surveying to precise staking using RTK guidance, as-built management using point cloud scans, and cloud integration of site data, allowing anyone to easily implement advanced digital construction management.

With LRTK, centimeter-level high-precision positioning and 3D scanning enable a single person to perform surveying and inspections efficiently. Features such as AR display of design drawings on the smartphone screen and RTK guidance that navigates the smartphone to specified coordinates to indicate stake positions help prevent construction errors and reduce labor. All information captured and recorded on-site is automatically synchronized to the cloud, so the office can immediately view and analyze data, enabling smooth real-time remote support and progress sharing.

The LRTK series is compatible with the Ministry of Land, Infrastructure, Transport and Tourism’s i-Construction initiatives, making it an optimal solution for promoting digitalization in construction and civil engineering. By adopting such advanced tools, solar construction sites can easily reap benefits like reduced manpower, higher accuracy, fewer errors, and faster information sharing. As a step toward accelerating the digital revolution on your sites, please consider using LRTK.

For more details about LRTK, please also see the [LRTK official site](https://www.lefixea.com/lrtk).