PVSyst Japanese Translation and LRTK Utilization: High-Precision Panel Placement Realized with AR

In designing solar power systems, high accuracy is required both for generation forecasting through simulation and for on-site construction. Especially for large-scale solar plants, faithfully reproducing a carefully developed plan on site is key to project success. This article first covers the main technical terms that appear in PVsyst, the global standard power simulation software, explaining their meanings in Japanese and their significance in design. Next, it introduces how the latest AR (augmented reality) technology, used in an LRTK solution, enables high-precision panel placement on site to match simulations. We will explore the points where this innovative workflow—bridging digital plans and real construction sites—greatly improves construction accuracy and efficiency for power plants.

Key PVsyst Terms and Japanese Translations

PVsyst offers advanced simulation capabilities, but its interface and reports frequently use English technical terms. Here we take up particularly important terms in PVsyst and explain what they refer to in Japanese.

• Orientation – This setting concerns the installation direction of PV panels. Specifically, it refers to the combination of which compass direction the panel faces (azimuth) and the angle at which it is tilted relative to the ground (tilt). A panel’s orientation has a major impact on the amount of solar irradiance received over the year, and optimal azimuth and tilt settings can maximize energy production.

• Irradiance – An indicator of sunlight intensity, it denotes the amount of solar radiation energy falling on a unit area. Simply put, it is the "solar irradiance" or solar radiation level. In PVsyst, simulations use the project site’s annual meteorological data (horizontal irradiance, temperature, precipitation, etc.). Understanding whether a region receives sufficient irradiance and how it varies seasonally is the basis for generation estimates.

• System Loss – A comprehensive indicator showing the proportion of energy received by the panels that is lost across the system. This includes losses due to soiling or reflection on the panel surface, resistive losses in cabling, output reduction from elevated temperatures, conversion efficiency losses in power conditioners (inverters), and temporary production losses from shading by surrounding objects. PVsyst accounts for these individual loss items to calculate how much output the overall system will be reduced. Designers check the simulation’s System Loss value and, if necessary, improve equipment configuration or layout to reduce losses.

The above terms frequently appear in PVsyst simulation settings and output. While the English terms may be less intuitive, understanding their meanings in Japanese makes it easier to evaluate design choices and interpret simulation results.

Significance in Design

The elements indicated by the PVsyst terms above are all crucial in solar power system design. Orientation (panel azimuth and tilt) determines how efficiently panels can capture sunlight over the year. For example, in Japan a generally south-facing orientation with an appropriate tilt is advantageous for maximum generation, but optimal orientations can change depending on site shape and surrounding obstructions. Optimizing orientation during design lets you maximize the energy obtained from a limited number of panels or installation area.

Irradiance is the system’s "fuel" and a fundamental condition for power generation. To accurately determine site irradiance conditions, designers collect annual irradiance data and meteorological information for the site. PVsyst can then calculate monthly and hourly generation. If irradiance estimates are incorrect, large discrepancies can occur between simulated and actual generation, so accurate assessment of irradiance is critical. Shading from nearby mountains or buildings also directly affects solar utilization. PVsyst can incorporate horizon profiles for distant terrain obstacles or model nearby trees and structures as 3D objects to compute shading patterns by time of day. These detailed settings enable generation forecasts that closely reflect reality.

System Loss shows that even with good irradiance and panel quantities, excessive system losses will prevent achieving expected output. Designers review various loss items calculated by PVsyst (wiring loss, conversion loss, temperature coefficient losses, shading loss, etc.) and take countermeasures. For example, increasing cable diameter reduces resistive losses; arranging panels to improve cooling reduces temperature-related losses; or reconfiguring layouts can decrease mutual shading. Minimizing system losses also improves the performance ratio. In other words, design efforts should ensure that energy gained from optimized Orientation and Irradiance is not wasted through losses.

Thus, the elements handled in PVsyst are directly linked not only to simulation but to actual design and construction planning. Rather than accepting simulation output at face value, correctly understanding and reflecting the underlying Orientation and Irradiance conditions and various loss factors enables planners to develop feasible and efficient solar projects from the planning stage.

Point Clouds from LRTK and AR Integration

To realize a design optimized by simulation on site, high-precision surveying data acquisition using LRTK and AR utilization are extremely powerful. LRTK consists of a compact RTK-GNSS receiver that attaches to a smartphone (iPhone/iPad) and a dedicated app, turning a smartphone into a centimeter-precision surveying instrument. Using RTK (Real-Time Kinematic) technology reduces positioning errors from several meters typical of standard GPS down to a few centimeters, so AR displays on the phone align precisely with the digital model and the real world.

LRTK also enables acquisition of on-site point cloud data (3D data composed of many measurement points) by leveraging the smartphone’s built-in LiDAR scanner. Walking the site while scanning with an iPhone records the terrain and structures as a high-density collection of points (point cloud). Combining this with RTK’s high-precision positioning gives the point cloud accurate coordinates in real space. From the obtained point cloud, you can understand terrain undulations and the positions and heights of existing objects, and convert them into 3D models useful for design.

For example, importing a detailed terrain model acquired by LRTK into PVsyst allows simulations that faithfully reproduce site elevation differences and surrounding obstructions. You can check subtle differences such as when each panel will enter shade during the day, which greatly aids layout optimization in the design phase. Conversely, you can import finalized design data (panel layouts and 3D racking models) into the LRTK app and overlay them on the point cloud for AR display on site. This lets you intuitively verify on the spot whether there are discrepancies between the digital plan and the actual terrain. The integration of point clouds and AR makes it possible to "accurately overlay the design model onto the site scenery," enabling early detection of interferences and layout issues that might not be apparent on paper.

On-Site Support with AR

Once high-precision survey data and 3D models are ready, AR-based on-site support can bridge the gap between design and construction. When viewing the site through a smartphone or tablet screen, the planned panel arrangement, reference lines, and equipment models are overlaid at full scale. Construction staff can view virtual panels and pile location markers superimposed on the real scene, allowing them to share the plan intuitively on site.

For example, during pile-driving work, virtual piles can be displayed in AR at the coordinates shown in the drawings. Workers simply walk to the marker shown on the screen to reach the exact pile-driving point. Traditionally, surveyors would mark the site for construction crews to follow, but AR visual guidance can greatly simplify this marking process and make accurate positioning possible even by a single person. As a result, even when driving hundreds or thousands of piles across a large site, keeping every pile in the exact planned position becomes manageable. Accurate pile locations reduce the amount of rework needed during later racking assembly, improving overall process efficiency and quality.

AR is also useful during racking and panel installation. By overlaying the design’s 3D model onto the assembled racking in AR, you can instantly check for errors in tilt angle, height, or spacing. On slopes, you can verify on the spot whether the racking is level and whether the prescribed tilt angle is achieved, preventing mistakes that would later reduce generation. You can also visually confirm with AR whether panel spacing and aisle widths match the design. Using AR for on-site support allows construction to proceed while directly comparing drawings and reality, making it easier to achieve construction that matches design accuracy without relying solely on workers’ experience or intuition.

Furthermore, conducting AR checks during construction enables on-the-spot design adjustments and smooth information sharing among stakeholders. For instance, immediately after earthworks, overlaying the terrain point cloud and design data in AR can instantly reveal that "the embankment is higher than planned" or "this area lacks sufficient excavation." If an issue is found, it can be shared with designers and supervisors on site and countermeasures can be discussed immediately. Correcting small deviations during construction is far less costly and labor-intensive than large rework after completion. By incorporating a process that constantly compares site conditions with the plan using AR, you can minimize inconsistencies between drawings and constructed elements.

Practical Workflow

Based on the above, here is an example practical workflow for achieving high-precision panel placement by combining PVsyst and LRTK.

• Site survey and data acquisition – First, use LRTK to survey the terrain and existing structures of the planned solar plant site. Attach the LRTK device to an iPhone and walk the site to measure and scan key points. This acquires point cloud data and survey coordinates that include accurate terrain features and the positions and heights of obstacles.

• Design simulation – Using the site data, perform generation simulations in design software (such as PVsyst). Import the acquired terrain model and surrounding obstruction information into PVsyst and develop panel layout proposals. Determine the optimal panel placement, azimuth and tilt, and equipment configuration on PVsyst while checking annual generation and loss values to finalize the design.

• AR-based placement verification – Once the design plan is finalized, load that data (panel layout plans and 3D models) into the LRTK AR app. Before construction, responsible personnel visit the site and confirm via their smartphone screens whether the panels can be placed as planned. Compare digital design and site conditions in AR for aspects such as racking heights against terrain undulations and distances to adjacent objects, and adjust the design as needed to improve consistency with the site.

• Construction and AR guidance – During on-site construction, use LRTK RTK positioning and AR displays to carry out pile-driving and racking installation exactly according to the design. Workers follow the guides shown on the phone screen; when they reach each pile-driving location, they can install without physical markings. During racking installation, compare components with the AR-displayed model and immediately correct any misalignment. AR guidance enables small crews to efficiently and accurately complete large numbers of installations.

• Inspection and recordkeeping – After installation, use AR to inspect the "as-built" condition. Overlay the design model on the installed panel rows on site to confirm whether placement, angles, and heights match the plan. Taking screenshots or video on the phone provides objective inspection records for storage and sharing. Since all survey data acquired by LRTK is saved to the cloud, it can also be used for reporting to owners or municipalities.

Benefits for Renewable Energy Developers, Designers, and Municipalities

The PVsyst and LRTK-based approach described above offers benefits to stakeholders involved in power generation projects.

• Benefits for renewable energy developers (power producers): Improved construction accuracy makes it easier to achieve planned generation. Reduced rework due to construction errors or design mismatches directly shortens schedules and cuts costs. Closer alignment of actual generation with simulation values improves investment return predictability. AR-based previsualization is also effective for explaining projects to local residents and investors, enhancing project transparency.

• Benefits for designers: Iterating between simulation and on-site verification allows designers to refine plans and minimize discrepancies between desk plans and actual site conditions. Detailed data from LRTK surveys enables high-precision planning from the design phase. On-site verification with AR can reveal issues designers may have missed on paper, improving design completeness. During construction, accurate communication of design intent to the field reduces question-and-answer exchanges and rework, letting designers focus on core design tasks.

• Benefits for municipalities (administrative officials): Precise design and construction management are reassuring for municipalities that grant project approvals. Being able to preview the completed appearance with AR aids consideration of landscape and safety concerns and helps share concrete images at public meetings. For post-construction inspections, AR allows efficient and more accurate comparison of drawings and works, improving inspection effectiveness. Digital records of construction facilitate future maintenance and troubleshooting. Municipalities also gain secondary benefits as high-quality renewable installations operate as planned, supporting local energy policy goals.

Conclusion

Combining PVsyst’s precise simulations with LRTK-enabled AR site support can dramatically improve the planning and construction accuracy of solar power plants. Digital-optimized panel layouts can be projected and implemented on site with matching precision, minimizing losses caused by discrepancies between design and construction. For power producers this leads to stable generation and reduced operational costs, and the approach offers wide benefits for all stakeholders. Finally, LRTK’s "lightweight surveying" capability allows anyone—not only specialist surveyors—to easily obtain centimeter-precision site data. As these technologies spread, high-precision panel placement planning and construction will become more accessible, contributing to the advancement of renewable energy projects.