PVsyst Japanese Translation and LRTK Utilization: High-Precision Panel Layout Achieved with AR

In designing solar power generation systems, high accuracy is required both for power generation predictions via simulation and for actual on-site construction. Especially for large-scale solar power plants, faithfully reproducing a carefully planned design on site is the key to project success. This article first takes up the main technical terms appearing in the world-standard power generation simulation software PVsyst, explaining their meanings in Japanese and their importance in design. Next, it introduces how the latest AR (Augmented Reality) technology combined with the LRTK solution can realize highly accurate panel layouts on site that match simulation results. Let’s look at the points by which this innovative workflow—connecting digital plans and real construction sites—dramatically improves the construction accuracy and efficiency of power plants.

PVsyst Key Terms and Japanese Translations

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

• Orientation（オリエンテーション：方位角・傾斜角） – This is the setting related to the installation direction of the solar panels. Specifically, it refers to the combination of which compass direction the panels face (azimuth) and the angle at which they are tilted relative to the ground (tilt). Panel Orientation greatly affects the amount of solar irradiance received throughout the year, and optimizing azimuth and tilt settings can maximize energy generation.

• Irradiance（イラディアンス：日射量） – An indicator of the strength of sunlight, meaning the amount of solar radiation energy falling on a unit area. Simply put, it is “irradiance” or solar insolation, also called solar intensity. In PVsyst, simulations use the project site’s annual meteorological data (horizontal plane irradiance, temperature, rainfall, etc.). Determining whether a region receives sufficient irradiance and understanding seasonal variations form the basis of generation forecasts.

• System Loss（システムロス：システム損失） – A comprehensive indicator showing the proportion of energy received by the panels that is lost across the entire system. For example, it includes losses due to soiling or reflection on the panel surface, losses from electrical resistance in wiring, reductions in panel output due to temperature rise, and conversion efficiency losses in power conditioners (inverters). Temporary non-generation periods due to shading from surrounding objects are also loss factors. PVsyst considers all these individual losses and calculates how much overall output is 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 results. Although the English terms may not be intuitively understood, understanding their meanings in Japanese makes it easier to discuss design details and interpret simulation results.

Significance in Design

The elements indicated by the PVsyst terms above all have important implications in solar power system design. Orientation (panel azimuth and tilt) determines how efficiently panels can capture solar irradiance over the year. For example, in Japan, generally south-facing panels with an appropriate tilt are advantageous for maximizing generation, but the optimal orientation can change depending on site shape and surrounding obstructions. By optimizing Orientation at the design stage, you can maximize the energy obtained from a limited number of panels or installation area.

Irradiance (solar insolation) is the basic condition and can be called the system’s “fuel.” To accurately grasp a target site’s irradiance conditions, designers gather the site’s annual solar data and weather information. PVsyst can calculate monthly and hourly generation based on this data. If irradiance estimates are incorrect, large differences may arise between simulation results and actual generation, so accurate assessment of Irradiance is critical. The effects of shading by nearby mountains or buildings also directly affect solar utilization. In PVsyst, distant terrain obstacles can be input as a horizon profile, and nearby trees or structures can be modeled as 3D objects to calculate shadowing for each time of day. Such detailed settings allow realistic generation forecasts.

System Loss indicates that even with favorable irradiance and panel count, large system losses prevent achieving expected output. Designers review the various loss items calculated by PVsyst (wiring loss, conversion loss, temperature coefficient losses, shading loss, etc.) and take countermeasures. For example, increasing cable diameter to reduce resistive loss, arranging panels to enhance cooling and suppress temperature-related losses, or re-layout of panels to reduce mutual shading—these optimizations are performed. Minimizing system losses also improves the Performance Ratio. In other words, it is crucial to ensure that energy gained through optimized Orientation and Irradiance is not wasted by losses.

As described above, the elements handled in PVsyst are directly linked not only to simulations but to actual design and construction planning. Rather than taking simulation results at face value, properly understanding and reflecting the underlying Orientation and Irradiance conditions and various loss factors enables you to plan realistic and efficient solar projects from the planning stage.

LRTK Point Clouds and AR Integration

To realize a simulation-optimized design on site, high-precision surveying data acquisition via LRTK and AR utilization are highly effective. LRTK consists of a compact RTK-GNSS receiver that attaches to a smartphone (iPhone/iPad) and a dedicated app, providing a solution that transforms a smartphone into a surveying instrument with cm level accuracy (half-inch accuracy). RTK (Real-Time Kinematic) technology can reduce positioning errors that were several meters with conventional GPS down to a few centimeters (a few inches), so AR displays on the smartphone align perfectly with digital models and the real world.

Furthermore, LRTK can acquire on-site point cloud data (3D data composed of many survey points) by leveraging the smartphone’s built-in LiDAR scanner. If you scan terrain and structures while walking the site with an iPhone, the shapes of the ground and obstacles are recorded as a dense collection of points (point cloud). Combining this with high-precision positioning from RTK assigns accurate real-world coordinates to the point cloud. From the obtained point cloud you can understand terrain undulation and the position/height of existing objects, and convert them into 3D models useful for design.

For example, importing a detailed terrain model acquired by LRTK into PVsyst enables simulations that faithfully reproduce site elevation differences and surrounding obstructions. You can pre-check subtle differences such as the exact times panels enter shade during the day, which greatly aids layout optimization at the design stage. Conversely, you can import finalized design data (panel layouts and 3D racking models) into the LRTK app and overlay them with point cloud data for AR display on site. This allows intuitive, on-the-spot verification of whether the digital plan and actual terrain align. Point cloud and AR integration makes it possible to “accurately overlay the design model onto the on-site scenery,” enabling early detection of interferences and layout issues that might not be noticed on paper.

AR On-Site Support

Once high-precision survey data and 3D models are ready, use AR on-site support to bridge the gap between design and construction. When the site is viewed through a smartphone or tablet screen, the planned panel layout, reference lines, and equipment models are overlaid at full scale. Construction staff can intuitively share the plan on site by seeing virtual panels and stake markers appearing in the real scene.

For example, during piling operations, you can make “virtual piles” appear on the smartphone AR display at the coordinates shown on the drawings. Workers simply walk to the marker shown on the screen to reach the exact pile point. Traditionally, surveyors set out reference marks on site and construction teams relied on those marks to drive piles, but AR visual guidance can greatly simplify this layout process and make it possible for a single person to perform accurate positioning. As a result, even on vast sites where hundreds to thousands of piles are driven, placing them all at design-specified positions becomes easy. Accurate pile positions reduce rework for racking assembly later, improving overall process efficiency and quality.

AR is also useful when installing racking and panels. By displaying the design’s 3D model over assembled racking in AR for comparison, you can instantly check for deviations in tilt, height, and spacing. On slopes, you can verify on the spot whether levelness is achieved and whether the specified tilt is maintained, preventing mistakes that would later reduce generation. You can also visually confirm with AR whether spacing between panels and aisle widths match the design. Using AR for on-site support lets you proceed with construction while comparing drawings and actual objects, making it easier to reproduce the design accuracy without relying solely on workers’ experience or intuition.

Moreover, performing AR checks during construction allows on-the-spot design modifications and smooth information sharing among stakeholders. For instance, right after earthworks, overlaying the terrain point cloud model and design data in AR can immediately reveal issues such as “the embankment is higher than planned” or “this area lacks sufficient excavation.” If a problem is found, it can be shared with designers and supervisors on site and countermeasures can be discussed immediately. Correcting small deviations during construction is less costly and labor-intensive than major rework after completion. By incorporating a process of constantly comparing site and plan with AR, you can reduce inconsistencies between drawings and built works to near zero.

Practical Workflow

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

• Site survey and data acquisition – First, use LRTK to survey the terrain and existing structures at the planned solar power site. Attach the LRTK device to an iPhone and walk the site while measuring and scanning key points. This acquires point cloud data and survey coordinates including accurate site topography and obstacle positions/heights.

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

• AR-based layout verification – Once the design plan is finalized, load that data (panel layout drawings and 3D models) into the LRTK AR app. Before construction begins, responsible personnel go to the actual site and verify via smartphone screen whether panels can be placed as planned. Compare digital design with on-site conditions in AR to check for issues related to terrain height differences, racking clearance, distances to adjacent objects, etc. Make design fine-tuning as needed to improve plan-site consistency.

• Construction and AR guidance – During on-site construction, use LRTK RTK positioning and AR displays to perform piling and rack installation according to the design drawings. Workers follow guides on the smartphone screen, and when they reach each pile position they can install without physical marking. During racking installation, compare with the AR-displayed model and correct any deviation immediately. AR guidance enables small crews to efficiently and accurately carry out large numbers of installations.

• Inspection and record – After installation, perform as-built inspections using AR. Overlay the design model on the installed panel rows on site to confirm layout, tilt, and height match the plan. Capturing screenshots or videos on the smartphone serves as objective inspection records for storage and sharing. All survey data obtained by LRTK is stored in the cloud, which can be used for reporting to clients or local authorities.

Benefits for Renewable Energy Developers, Designers, and Municipalities

The PVsyst and LRTK-based approach described above benefits stakeholders across the power generation business.

• Benefits for renewable energy developers (generation operators): Improved construction accuracy makes it easier to achieve planned generation. Reduced rework due to construction errors or design misalignment leads directly to shorter schedules and cost savings. When actual generation approaches simulation values, the accuracy of investment return forecasts also improves. Pre-checking the completed appearance with AR is useful for explaining projects to local residents and investors, contributing to project transparency.

• Benefits for designers: Being able to iterate between simulation and on-site verification minimizes discrepancies between desk plans and site reality. Detailed data from LRTK surveying enables high-accuracy planning from the design stage. On-site verification with AR often reveals issues designers missed on drawings, improving the quality of designs. During construction, design intent is more accurately conveyed to the site, reducing time spent on queries and rework and allowing designers to focus on core design tasks.

• Benefits for municipalities (administrative staff): Precise design and construction management provide assurance to municipalities responsible for permitting and approvals. The ability to pre-check completion renderings in AR facilitates consideration of landscape and safety concerns and enables concrete image sharing at community briefings. For post-construction inspections, AR allows verification by comparing design drawings and constructed works, enabling more efficient and accurate inspections than before. Digital records of construction also help with future maintenance and troubleshooting. For municipalities, high-quality renewable energy facilities operating as planned support regional energy policy goals and produce positive ripple effects.

Conclusion

Combining PVsyst’s detailed simulations with LRTK-enabled AR on-site support significantly improves the planning and construction accuracy of solar power plants. Because a digitally optimized panel layout can be projected and implemented on site with the same precision, losses due to design-construction mismatches are minimized. This leads to stable generation and reduced operating costs for developers, and the approach offers wide benefits to all stakeholders. Finally, LRTK’s simple surveying functions now allow anyone—not just professional surveyors—to easily acquire site data with cm level accuracy (half-inch accuracy). As such technologies become widespread, high-precision panel layout planning and construction will become more accessible, contributing to the promotion of renewable energy projects.