PVSyst Japanese Translation — Basic Settings: How to Use LRTK Survey Data

Introduction

One indispensable tool for designing and forecasting output of photovoltaic systems is PVSyst. PVSyst is the world-standard PV simulation software that can calculate power generation with high accuracy by inputting meteorological data, panel layouts, and more. However, since much of the interface and documentation is in English, it can be a barrier for beginners in Japan. This article serves as a basic setup guide for a PVSyst Japanese translation, explaining in an easy-to-understand way everything from initial setup to panel configuration, tilt and azimuth settings, and shading. It also discusses the importance of on-site survey data—which is key to improving simulation accuracy—and the limitations of manual settings, and introduces how to leverage a high-precision surveying solution, LRTK. This should be useful for those seeking information about PVSyst Japanese translation.

PVSyst Basic Setup Guide (with Japanese translation)

This section explains in Japanese the basic configuration items when running PV system simulations in PVSyst. If you are using PVSyst for the first time, try setting up your project by following the steps below.

Initial setup: project and meteorological data input

First, launch PVSyst and create a new project. Specify the “Project Name” and set the folder where the project will be saved. Then select the system type (grid-connected or off-grid). Next, define the site location. Specifically, either enter the plant’s latitude and longitude or select the city name from PVSyst’s built-in list. Set the appropriate meteorological data for the location here. For example, you can obtain the region’s annual irradiation and temperature data from datasets such as Meteonorm, SolarGIS, or NEDO. Because irradiation values vary by meteorological data source, it is advisable to compare multiple sources and choose the one closest to reality. By selecting appropriate meteorological data, PVSyst will accurately reflect the site’s annual solar conditions in the simulation.

Panel configuration and system specifications

Next, configure the PV system. Select the PV modules and inverters from PVSyst’s database and add them to the system. Key specs such as module nominal power and conversion efficiency, and inverter nominal capacity and European efficiency are automatically populated. Then define how modules will be connected—specifically, set the number of modules in series (the number of modules per string) and the number of parallel strings to determine the total number of panels in the array. This yields the system’s DC capacity and allows you to check the DC/AC ratio (oversize ratio) in relation to the number of inverters. You can also set system loss parameters such as wiring losses and transformer losses, but beginners may leave defaults as-is. Up to this point, the panels, inverters, and overall system size have been defined within PVSyst.

Tilt and azimuth settings

Setting the tilt angle and azimuth angle is an important step that specifies which direction the panel surface faces and at what angle it is inclined. The tilt angle indicates how many degrees the panel is raised from the horizontal plane; in Japanese it is called "傾斜角" or "傾斜度". For example, a tilt of 0° is horizontal and 90° is vertical. Generally, a tilt close to the installation latitude maximizes annual generation, but the optimal angle varies depending on installation conditions. The azimuth angle indicates the compass direction the panel faces, expressed in degrees. Azimuth is usually represented with true south as 0° (or 180°) and east/west expressed with ±; in PVSyst the default is true south = 0° and positive angles toward the west. For example, south-facing installation uses Azimuth = 0°, due east uses -90°, and due west uses +90°. In many cases in Japan, arrays face due south or slightly west of south. Correctly setting tilt and azimuth ensures the simulation reflects the irradiance conditions for that panel arrangement. If you use a tracking system, PVSyst can be configured for 1-axis or 2-axis tracking, but for beginners it’s recommended to start with a fixed tilt configuration.

Shading settings (horizon and near objects)

Shading is another crucial PVSyst feature that affects panel output. Shading factors can be broadly divided into two types: distant terrain shading and shading from nearby objects.

Shading from the horizon refers to distant terrain such as mountains or high ground on the horizon blocking sunlight. In PVSyst, you can set a "horizon profile" that specifies the elevation angle of the horizon for each azimuth. For example, if mountain ranges surround the site to the southwest, entering the horizon elevation angle for that direction allows the simulation to reflect periods in the morning or evening when the sun is obscured by those mountains. Horizon data can be obtained by taking all-sky photos with a fisheye lens camera on-site or derived from survey data, but it may be hard for beginners to prepare immediately. In early stages, if the surrounding terrain is flat, you may assume a flat horizon (0°) and proceed.

Near shadings are shadows caused by objects located within or immediately around the plant site, such as buildings, trees, utility poles, or adjacent panel rows. PVSyst’s 3D Scene feature enables detailed shading analysis by modeling these nearby objects in three dimensions. Specifically, in the "Shading scene construction" screen you place the panel array as a 3D model and add surrounding buildings or trees as objects with specified heights and positions. For instance, if there is a 10 m tall tree to the southeast, placing it as a 3D object allows PVSyst to compute that tree’s shading impact on the panels throughout the year. PVSyst uses the scene information to calculate shading at each time step and reflects the monthly shading losses in the result reports. Beginners may skip this step initially if there are no shading factors, but in real projects shading settings are essential for simulation accuracy.

That covers the basic setup flow explained in the PVSyst Japanese translation. By correctly configuring the project location and meteorological conditions, module and equipment configuration, tilt and azimuth, and shading conditions, PVSyst can provide detailed predictions of annual generation and losses for the design. Remember that the more accurate the configuration items, the higher the reliability of the simulation results.

The importance of on-site survey data and the limits of manual settings

In PVSyst simulations, the accuracy of input data determines the result’s precision. However, obtaining all necessary data comprehensively and accurately is not easy. Here we consider the importance of on-site survey data and the limitations of conventional manual setup methods.

Input data determines simulation accuracy: As mentioned above, PVSyst allows input not only of panel layout and tilt/azimuth but also of surrounding terrain and shading from buildings and trees. The more precise the inputs, the closer the results will reflect reality. But collecting such detailed data itself is often challenging. For example, creating a horizon profile to account for distant mountain shading requires measuring horizon elevation angles for each azimuth using a compass and an inclinometer, or taking all-sky photos with a specialized fisheye camera and analyzing them. To know fine topographic variations inside and around the site you need detailed land surveys by a surveyor or 3D maps from drone photogrammetry. These traditional methods are time-consuming, labor-intensive, and often require expensive equipment and specialist skills.

Limits of manual settings: If survey instruments are not available, designers may resort to "manual settings"—estimating heights from topographic maps or satellite images, visually inspecting the site to guess the heights of major shading objects, and entering those estimates. However, this method inevitably leaves inaccuracies. Satellite images and public maps have limitations in resolution and currency; for example, a newly built structure or a tree that has grown since aerial photos were taken may not appear. Furthermore, shading effects vary with date and time, so observations made only on a particular day cannot capture the shading impact across the entire year. When settings are based on incomplete data or assumptions, PVSyst’s precise calculations will still follow the principle “garbage in, garbage out,” resulting in errors. Consequently, simulation outputs may diverge significantly from actual generation, and an optimized design might not perform as expected in practice.

For these reasons, obtaining high-precision on-site survey data is key to improving simulation accuracy. If the site’s topography is captured to centimeter-level precision and the positions and heights of surrounding obstructions are accurately measured and reflected in PVSyst, it becomes possible to estimate shading effects and irradiation losses precisely. However, when people hear "high-precision surveying" they may imagine contracting a surveying firm or using expensive laser scanners. In recent years, solutions that make this achievable more easily have emerged. One such solution is LRTK.

Leveraging high-precision survey data with LRTK

LRTK is a cutting-edge technology for efficiently acquiring detailed on-site data. This section explains what LRTK is, how it works, its features, and how the acquired data can be applied to PVSyst design.

What is LRTK? Centimeter positioning using a smartphone

LRTK refers to a compact RTK-GNSS receiver device that attaches to a smartphone (currently mainly iPhone/iPad) and the associated system. RTK stands for "Real-Time Kinematic," a technique that enables high-precision positioning by applying real-time corrections to satellite positioning (GPS, etc.). While ordinary GPS has errors on the order of meters, RTK can achieve errors of only a few centimeters. LRTK is designed so that anyone can easily use RTK positioning simply by attaching the device to a smartphone and launching its dedicated app.

The LRTK hardware is small and lightweight enough to fit in a pocket, with the antenna and battery integrated. This eliminates the need for complex wiring or bulky equipment; you can survey the site just by walking with a smartphone. Usage is simple: bring the smartphone to the point to be measured and tap a button in the app to record that moment’s latitude, longitude, and elevation with centimeter-level accuracy. Recorded points can include timestamps and notes, so labeling them as "SW corner of point A" or "top of hill at point B" makes later data organization easier.

Strength in offline environments: LRTK supports the correction signals provided by Japan’s quasi-zenith satellite system (for example, CLAS), enabling it to maintain high-precision positioning even in areas without mobile network coverage, such as mountain regions. Since PV plants are often sited in mountainous or remote areas where conventional RTK positioning is hindered by lack of cellular connectivity, LRTK’s ability to receive augmentation signals directly from satellites allows surveying to continue. This makes it possible to perform centimeter-precision surveying with just an iPhone regardless of communication infrastructure.

Efficiency and sharing: Positioning data recorded with LRTK can be uploaded to the cloud in real time. Measured points are plotted on a map on the spot and can be shared immediately with remote team members. Because distances and elevation differences between any two points can be calculated instantly on-site, there’s no need to use measuring tapes or levels or take manual notes. With one smartphone per person, multiple people can divide the work and survey large areas quickly. Tasks that used to take days can be dramatically shortened using LRTK.

Obtaining point cloud data and applying it to PVSyst

LRTK’s real value goes beyond point-by-point positioning. Modern iPhones include a LiDAR scanner that can capture the surrounding environment as 3D point cloud data. The LRTK app can combine this LiDAR capability with high-precision positioning to perform on-site 3D scans. By walking through the site while holding a smartphone, the terrain and structures in front of you are recorded as point cloud data (a set of many measured points). Because LRTK’s high-precision GNSS provides accurate absolute coordinates (world coordinates) to the captured point cloud from the outset, there is no need for post-scan georeferencing.

Traditionally, obtaining 3D point cloud data required terrestrial laser scanners set on tripods with multiple scans, or drone photogrammetry followed by 3D reconstruction. Terrestrial laser scanners are expensive and require specialized operation, and drone photogrammetry often needs pre-placed control points to achieve high accuracy and cannot capture areas obscured from above—such as under tree canopies or building overhangs. In contrast, iPhone scans with LRTK allow a person to enter under obstacles and into narrow spaces to capture missing data, and real-time distortion correction while walking results in a highly accurate, comprehensive 3D representation of the site.

Captured point cloud data can be uploaded to the cloud and utilized. A dedicated web platform allows viewing in a browser and conducting necessary measurements without survey CAD software. For example, you can calculate distances between any two points, areas, and volumes with a click, or slice cross-sections to check terrain undulations. For PV plant planning, this point cloud data is very useful. Creating a current terrain model from the point cloud enables precise planning for earthworks. By acquiring site topography before construction and overlaying it with the planned design terrain, you can automatically compute where and how much fill or cut is required. Earthwork calculations that used to take civil engineers considerable time can be greatly streamlined using LRTK data.

Improved shading analysis in PVSyst: Point cloud data captured with LRTK includes detailed representations of surrounding trees and structures. Analyzing these allows you to obtain high-precision information required for shading analysis in PVSyst. For example, if you scan surrounding forest areas with an iPhone, you can determine each tree’s height and position with centimeter-level accuracy. From that data you can calculate the occlusion angles relative to solar elevation (the horizon profile for each azimuth and the vertical extent of each tree) and reflect these values in PVSyst’s near shading inputs to more accurately estimate seasonal and diurnal generation losses. In practice, generating a 3D terrain model from LRTK-derived topography and reconstructing the panel layout on it to import into PVSyst enables advanced analyses—such as simulating when and how much each panel will be shaded as an animation. At this level, the simulation becomes a digital twin of the actual site, minimizing discrepancies between predicted and actual post-construction generation.

Improved design efficiency: Using LRTK enhances not only simulation accuracy but also design process efficiency. Because high-precision survey data can be obtained quickly, planning can proceed much faster. Site surveys that previously required contracting surveyors or obtaining drone flight permits can be carried out quickly by the project team using LRTK. There is no need to transport heavy equipment or allocate large teams—one person can survey a wide site. Moreover, because LRTK data can be shared via the cloud immediately, the on-site team can consult with the head office design team in real time to decide on direction. As a result, redundant iterations and design errors caused by insufficient site checks are reduced, leading to lower costs and faster project timelines.

Conclusion: Achieving both simulation accuracy and design efficiency with LRTK

PVSyst-based PV simulations achieve their greatest value when appropriate settings and accurate input data are in place. This article explained the basic setup methods in a PVSyst Japanese translation, discussed the importance of on-site data, and introduced the latest surveying technology, LRTK. By adopting LRTK, you can reflect real on-site information in simulations while greatly improving design efficiency. Balancing precise simulations based on high-precision on-site survey data with a smart design process will increase the success rate of PV projects.

In an era where *centimeter-precision surveying with only an iPhone* is now a reality, there’s no reason not to take advantage of it. Use LRTK to experience reliable simulations and optimal designs based on on-site data in your next project. Detailed feature descriptions and how to adopt LRTK Phone are available on the official site’s [LRTK product page](https://www.lrtk.lefixea.com/lrtk-phone). If you’re interested, feel free to contact them via the [inquiry form](https://www.lefixea.com/contact-lrtk). Adopt LRTK and take your PV plant designs to the next stage with both accuracy and efficiency.