Must-see at the Solar Exhibition: Dramatically Improve Pre-construction Surveys with Point Cloud Scanning × Cloud Reporting

Introduction

With growing attention to renewable energy, large-scale solar power projects are underway across the country. In this context, improving on-site efficiency is an urgent issue. In particular, the site pre-construction survey (current condition surveying and verification) conducted before installing solar panels is a critical step that directly affects the overall project schedule and construction accuracy. Solar power plants are often built in mountainous areas or on vast former farmland, and conventional surveying methods make it difficult to accurately grasp terrain across every part of a site. However, if terrain can be digitized in detail, it becomes easier to plan optimal solar panel layouts and earthwork, and to consider shading or drainage issues in advance. One approach gaining attention at the Solar Exhibition is the survey method combining point cloud scanning × cloud reporting. This article explains in detail, with concrete examples, how this method improves efficiency compared to traditional survey methods. If you want to pursue DX (digitalization) at solar power sites, please refer to this.

Traditional pre-construction surveys and challenges

Traditionally, pre-construction surveys for solar power plants have relied mainly on manual labor and paper drawings. Professional surveyors enter forests and fields and measure terrain elevations point by point with transits or GPS instruments, then create contour maps and cross-sectional terrain diagrams. This method takes time and effort to measure large sites, and depending on point spacing there is a risk of overlooking subtle undulations or changes in terrain. Survey results are compiled into paper drawings and reports and distributed to project stakeholders, but this paper-based reporting makes it difficult to share a clear image of the site and conveys little nuance in the details.

In recent years, new methods such as drone surveying have appeared, allowing terrain data to be obtained from the air faster than manual methods. Photogrammetry from drones can produce orthophotos (top-down images) and digital terrain models that enable a fairly detailed understanding of terrain. However, post-processing of drone-captured data requires specialized software and high-performance PCs and can take several days for analysis. The resulting 3D models and point cloud data are also large, so to share them with all site stakeholders they are often converted into static plans or PDF reports, lacking real-time interaction and two-way communication. Thus, conventional methods introduce time lags from surveying to reporting and decision-making, leaving room for efficiency improvements. If initial surveys are inadequate, problems such as “the slope was steeper than expected” or “there isn’t enough fill” may surface once earthwork begins, leading to redesigns and extended schedules. Low survey accuracy and information sharing errors can cause significant rework in later stages.

What are point cloud scanning and cloud reporting

Point cloud scanning is a technique that digitally measures terrain and structures as countless points (point clouds) using laser survey instruments (LiDAR) or photogrammetry. The resulting point cloud data can be considered a three-dimensional model that faithfully reproduces the site’s undulations and features. It is like creating a complete digital copy (site digital twin) of the field, enabling the capture of fine bumps and hollows that conventional survey drawings cannot represent. For example, if a high-performance laser scanner measures a forested area, millions of points including trees and terrain undulations can be collected, producing a realistic point cloud model that captures the entire site. Additionally, acquired point clouds can include color information per point, allowing the site to be reproduced with photo-like appearance. By georeferencing to a surveying coordinate system, the data can be accurately overlaid on drawings and used to calculate distances and areas. Although point cloud acquisition has been possible for some time, it previously required dedicated 3D laser scanner equipment and experienced operators, making it costly and difficult to adopt for small projects. However, recent technological advances have brought lightweight LiDAR for drones and easy scanning methods using smartphone-integrated LiDAR sensors, enabling low-cost, high-density 3D surveying. 3D surveying that was once limited to large projects is now becoming usable on small and medium-sized sites.

On the other hand, cloud reporting refers to uploading acquired digital site data to the cloud and sharing, viewing, and editing it via the internet among stakeholders. If point cloud data and terrain models are hosted on a cloud platform, each participant can interactively review the data from a web browser on their PC or tablet. There is no need to install dedicated software; users can freely rotate and zoom 3D models, measure lengths, areas, and volumes, overlay CAD design drawings for review, and perform these tasks intuitively even if they are off-site. In other words, cloud-based virtual site inspections become possible.

How site surveys change by combining point cloud data × cloud utilization

Sharing detailed terrain data acquired by point cloud scanning via the cloud dramatically streamlines the flow from solar site survey to reporting. Below are specific benefits compared with traditional methods.

• Rapid and comprehensive data acquisition: Surveying a large site that would take days by manual methods can be completed in a short time with drones or LiDAR scanning. For example, a single drone flying over an entire site can capture point cloud data of several million points in just a few hours. Not only is surveying time greatly reduced, but data is not missed in steep or hard-to-access areas. As a result, “measurement omissions” and the need for re-surveys are reduced, yielding accurate and comprehensive as-built data from the start. There is also a major safety benefit since people do not need to enter hazardous areas. In some cases, surveying time can be reduced to less than one-tenth of conventional methods, avoiding project delays caused by awaiting surveys. Moreover, using the latest smartphone-mounted scanners, workers can walk the site immediately after earthwork to capture point clouds and verify the finish on the spot, enabling rapid feedback.

• Easy sharing and smoother consensus building: 3D models uploaded to the cloud can be viewed by all project stakeholders—designers, construction managers, clients—so everyone examines the same data. Height differences and terrain quirks that were hard to convey with paper drawings or numerical data become obvious when shared as three-dimensional visuals. For example, designers can simulate solar panel placement on point cloud data and decide precisely, “Cut this hill for earthwork” or “Fill this valley.” Site representatives and construction teams can intuitively understand conditions from a 3D model more easily than from number-filled reports, reducing misunderstandings. Because everyone can exchange opinions while looking at the same digital site, consensus building accelerates dramatically. In addition, direct marking and commenting on the cloud model allow issues to be shared immediately, enabling communication without loss.

• Understand the site and approve remotely in real time: Point cloud data shared on the cloud is accessible anywhere with an internet connection. This allows headquarters staff to virtually inspect site terrain from the office and issue additional instructions. For example, survey data for a planned site in a rural mountain area can be reviewed the same day by Tokyo headquarters staff, who can give the go-ahead with a “construction possible as planned” remote approval. Processes that traditionally required on-site visits and meetings can be completed online, significantly reducing travel time and cost. Recently, efforts combining point cloud data with 360-degree camera imagery enable headquarters staff to experience the site remotely with VR goggles. Being able to check details in a virtual space without traveling has reportedly cut travel time dramatically. Because staff can grasp conditions visually without visiting, a small team can efficiently oversee multiple remote sites.

• Streamlined reporting and revision handling: Data acquired on site can be shared via the cloud the same day, speeding up report creation. If needed, cross sections and height distribution maps can be automatically generated from point cloud data and presented to stakeholders immediately. Compared to paper reports, cloud reports convey much more information and detail about current conditions, reducing the need for additional explanations. When new findings or design changes arise, updating the cloud with revised data ensures everyone sees the latest version. Version control and explaining differences become easy, minimizing discrepancies and rework. For example, overlaying terrain data with the design model can reveal issues like “the north panels will be shaded as is,” which can then be corrected during the design phase. Processes that used to take weeks to reflect initial surveys into design changes can be completed in just a few days, or in some cases the same day with point cloud data, shortening the project lead time. Systems are also being developed to automatically generate as-built inspection reports (inspection records) from point cloud data, enabling photo-equipped reports to be produced at the push of a button. The effort required for record creation is steadily decreasing.

• Advanced earthwork planning and schedule management: Detailed as-built point cloud data directly improves the accuracy of earthwork (cut and fill) planning. Elevation differences and slopes can be automatically calculated from the acquired terrain model, quantifying how much soil must be added or removed at each location. Even in complex terrain, comparing point cloud datasets makes it possible to instantly compute cut and fill volumes, which is more reliable than manual calculations or rule-of-thumb estimates. This prevents excess or shortages of fill and enables proper planning of heavy equipment and dump trucks. Re-scanning with drones or smartphones during earthwork and comparing the current status to the design model allows immediate verification of whether finished ground levels and slopes meet design. Color-coding elevation differences on the cloud visually shows which areas are under-excavated or overfilled, so additional grading instructions can be issued on the spot. Repeating this feedback during construction helps prevent rework and over-execution, leading to shorter schedules and cost savings. Additionally, 3D terrain-based rainfall runoff simulations can evaluate flood risk and inform proper placement of drainage facilities, aiding environmental mitigation planning. Issues that used to be discovered after construction can be identified in advance, enabling safer project execution.

• Smoother consultations with municipalities and external explanations: Developing a solar power plant requires consultations with local municipalities and explanations to residents. Point cloud data and cloud utilization are powerful tools in these situations as well. For example, when opening a forest for earthwork, sharing cloud-based materials that compare current 3D terrain with the post-earthwork image helps municipal officials form a concrete impression. Explaining “this valley will be filled to this level” or “we will create a retention pond here” with a 3D model rather than only plan views speeds up identification of concerns and consensus building. Because sufficient information can be provided online without sending large files by email or calling stakeholders to the site, the time spent on administrative procedures and external coordination can be reduced. Explanations based on accurate 3D materials are more persuasive and can reduce the number of review cycles required. In resident information sessions, showing completed image 3D models on a tablet helps non-experts intuitively understand plans without technical jargon.

Note that challenges such as large point cloud file sizes and specialized software operation are being steadily reduced by advances in cloud services and user-friendly apps. These technological innovations are creating an environment in which anyone, including non-experts, can enjoy these benefits.

Conclusion: The future of solar development opened by digital technology

By leveraging point cloud scanning and cloud reporting, the speed of information sharing and decision-making from pre-construction surveys to construction in solar power development dramatically improves. High-precision survey data enables accurate construction on the first attempt, contributing to improved quality. Projects that have adopted this approach report that feedback time from surveying to design has been reduced to a fraction of previous durations, and rework due to design changes has decreased substantially. This method, a representative of on-site DX (digital transformation), has gained enough industry attention to be featured as a “must-see” topic at the Solar Exhibition. The Ministry of Land, Infrastructure, Transport and Tourism is also promoting the use of 3D data at construction sites, and adopting point cloud technology is truly a trend of the times. Surveying and reporting processes that once relied on manpower and experience are being transformed into systems where anyone can accurately grasp current conditions via digital data. As a result, limited personnel can handle multiple projects in parallel, helping to solve labor shortages and achieve shorter schedules and cost reductions. Such productivity improvements are important responses to worsening labor shortages and workstyle reforms that limit long working hours. Furthermore, if the entire site is scanned as a point cloud at project completion and digitally recorded, the data can be used for future maintenance planning and ledger creation, further reducing documentation effort. The paper-centered style of surveying and reporting is beginning to change dramatically through digitalization. Smart survey methods using 3D point clouds and the cloud are likely to become the new standard across construction, not just in solar power.

If you have the chance to see a demo of point cloud scanning and cloud sharing at the Solar Exhibition venue, be sure to experience the power of this efficiency firsthand. You should be able to sense the benefits that digital technology brings to the field.

Finally, a technology that further brings on-site surveying digitalization within easy reach is the solution called “LRTK smartphone surveying”, which combines smartphones with high-precision GNSS to enable anyone to perform precise surveying easily. With simple操作, 3D point clouds can be acquired and shared to the cloud, greatly contributing to the efficiency of small-scale site checks and routine measurement tasks. Surveys that used to be conducted by teams can be completed by a single person, significantly reducing on-site burden. Adopt survey methods using the latest technologies to achieve DX and productivity improvements at solar power sites.